Implementation of targeted inpatient glycemic control by a multidisciplinary team in the hospital is a time‐intensive and labor‐intensive undertaking. A variety of business models may be applied including those in which the hospital provides financial support and those which will be self‐supporting through clinical billing revenues (Table 1). In practice, a combination of these strategies may be used.

In order to make the case to hospital administration for investment of financial support for glycemic control programs, it is necessary to develop a business plan that will justify return on investment. The following discussion is a composite of information from the published literature, personal communication with hospital glycemic control champions, and the author's experience developing, implementing, and assessing outcomes for a glycemic control task force charged with improving glucose control in the 7 hospital MedStar Health system from which more than 45,000 patients are discharged annually with a diagnosis of diabetes.

The principles for making the business case for support of a glycemic control team are the same as those applied in other hospital‐based programs. While the clinical argument for a new process, resource, or staff member may be sound, the business plan will also be analyzed from nonclinical perspectives, with attention to its fiscal and operational feasibility. It is therefore important to involve hospital administration, operations, and finance representatives early, in order to obtain their support and address concerns early that would otherwise weaken the request. The information provided in this article is intended to provide practical guidance for developing a plan that is realistic and tailored to the needs of the individual institution.

A. HOSPITAL‐SUPPORTED MODELS

The business case for hospital support for the glycemic control team is based on opportunities to improve revenue through accurate documentation and coding, reduction in length of stay, and optimization of resource utilization through reduction in morbidity and mortality (cost aversion).

In order to understand opportunities for improved revenue, it is necessary to understand how hospitals are reimbursed for inpatient care. Medical record documentation is reviewed by hospital coding personnel who apply strict guidelines and ICD‐9‐CM nomenclature to establish the diagnoses and procedures for each case. The ICD‐9‐CM is a numerical coding scheme of more than 13,000 diagnoses and 5,000 procedures. The principal and secondary diagnoses and procedures are grouped into a Diagnosis Related Group (DRG) code. In most states, CMS (Medicare) reimburses hospitals a flat rate based on the DRG code assigned to each inpatient case. CMS calculates a specific DRG weight for each DRG code. The DRG weight is a number such as 0.895 or 1.24, which reflects the acuity of the patient assigned to a particular DRG code and expected resource utilization. The greater the weight, the greater the acuity and expected resource utilization. The overall Case Mix Index (CMI) is the simple average of the DRG weight for a population of inpatients. CMI indicates the relative severity of a patient population and is directly proportional to DRG payments. This index is valuable when making comparisons between hospitals or patient groups.

Each hospital is provided a single rate relative to a DRG weight of 1.0 which allows calculation of the expected revenue from CMS per case. The DRG payment for a Medicare patient is determined by multiplying the relative weight for the DRG by the hospital's blended rate: DRG PAYMENT = WEIGHT RATE. Each hospital's payment rate is defined by federal regulations and is updated annually to reflect inflation, technical adjustments, and budgetary constraints. There are separate rate calculations for large urban hospitals and other hospitals. There are also technical adjustments for local wage variations, teaching hospitals, and hospitals with a disproportionate share of indigent patients.1

Determination of allowable charges for inpatient care varies by location and payor. The State of Maryland, for example regulates hospital inpatient charges for all patients based on the CMI of each hospital. In this reimbursement system, the hospital must ensure that their total average charge per case is on par with their reported CMI, when compared to other hospitals. For non‐Medicare payors, reimbursement may also be based on a set DRG payment or a percentage of charges based on contractual stipulations. The business case will be based on the individual hospital's allowed charges.

Empirical studies in this area are lacking, perhaps in part because this is a sensitive data area. Publications tend to focus on potential rather than actual results. Profiling hospital improvement management performance for documentation, coding and reimbursement does allow hospitals to go beyond focused operational metrics to evaluate themselves in a broad industry context to determine whether they are in alignment with examples from other institutions.2

Given this background, specific strategies used to justify hospital support for the glycemic control will now be outlined.

B. REVENUE GENERATION THROUGH BILLING FOR CLINICAL SERVICES

Implementation of targeted BG control in the hospital provides opportunities for an increase in the provision of clinical consultative services for diabetes management. Physicians and allied healthcare providers can bill when they provide such care, and the revenues offset costs of salary, fringe benefits and other expenses.

CONCLUSION

Financial justification for support of a hospital based glycemic control team is challenging but possible, as has been shown by Newton5 and by DeSantis and Molitch.10 Various models may be used individually or in combination to make the case to hospital administration for salary support for team members. The models that may be helpful in this regard include: improved documentation opportunities; reduction in length of stay; reimbursement for direct clinical diabetes case management consultative services by physicians and NPs or PAs, and demonstration of improved resource utilization for the hyperglycemic patient managed by the hospital glycemic control team.

Implementation of targeted inpatient glycemic control by a multidisciplinary team in the hospital is a time‐intensive and labor‐intensive undertaking. A variety of business models may be applied including those in which the hospital provides financial support and those which will be self‐supporting through clinical billing revenues (Table 1). In practice, a combination of these strategies may be used.

In order to make the case to hospital administration for investment of financial support for glycemic control programs, it is necessary to develop a business plan that will justify return on investment. The following discussion is a composite of information from the published literature, personal communication with hospital glycemic control champions, and the author's experience developing, implementing, and assessing outcomes for a glycemic control task force charged with improving glucose control in the 7 hospital MedStar Health system from which more than 45,000 patients are discharged annually with a diagnosis of diabetes.

The principles for making the business case for support of a glycemic control team are the same as those applied in other hospital‐based programs. While the clinical argument for a new process, resource, or staff member may be sound, the business plan will also be analyzed from nonclinical perspectives, with attention to its fiscal and operational feasibility. It is therefore important to involve hospital administration, operations, and finance representatives early, in order to obtain their support and address concerns early that would otherwise weaken the request. The information provided in this article is intended to provide practical guidance for developing a plan that is realistic and tailored to the needs of the individual institution.

A. HOSPITAL‐SUPPORTED MODELS

The business case for hospital support for the glycemic control team is based on opportunities to improve revenue through accurate documentation and coding, reduction in length of stay, and optimization of resource utilization through reduction in morbidity and mortality (cost aversion).

In order to understand opportunities for improved revenue, it is necessary to understand how hospitals are reimbursed for inpatient care. Medical record documentation is reviewed by hospital coding personnel who apply strict guidelines and ICD‐9‐CM nomenclature to establish the diagnoses and procedures for each case. The ICD‐9‐CM is a numerical coding scheme of more than 13,000 diagnoses and 5,000 procedures. The principal and secondary diagnoses and procedures are grouped into a Diagnosis Related Group (DRG) code. In most states, CMS (Medicare) reimburses hospitals a flat rate based on the DRG code assigned to each inpatient case. CMS calculates a specific DRG weight for each DRG code. The DRG weight is a number such as 0.895 or 1.24, which reflects the acuity of the patient assigned to a particular DRG code and expected resource utilization. The greater the weight, the greater the acuity and expected resource utilization. The overall Case Mix Index (CMI) is the simple average of the DRG weight for a population of inpatients. CMI indicates the relative severity of a patient population and is directly proportional to DRG payments. This index is valuable when making comparisons between hospitals or patient groups.

Each hospital is provided a single rate relative to a DRG weight of 1.0 which allows calculation of the expected revenue from CMS per case. The DRG payment for a Medicare patient is determined by multiplying the relative weight for the DRG by the hospital's blended rate: DRG PAYMENT = WEIGHT RATE. Each hospital's payment rate is defined by federal regulations and is updated annually to reflect inflation, technical adjustments, and budgetary constraints. There are separate rate calculations for large urban hospitals and other hospitals. There are also technical adjustments for local wage variations, teaching hospitals, and hospitals with a disproportionate share of indigent patients.1

Determination of allowable charges for inpatient care varies by location and payor. The State of Maryland, for example regulates hospital inpatient charges for all patients based on the CMI of each hospital. In this reimbursement system, the hospital must ensure that their total average charge per case is on par with their reported CMI, when compared to other hospitals. For non‐Medicare payors, reimbursement may also be based on a set DRG payment or a percentage of charges based on contractual stipulations. The business case will be based on the individual hospital's allowed charges.

Empirical studies in this area are lacking, perhaps in part because this is a sensitive data area. Publications tend to focus on potential rather than actual results. Profiling hospital improvement management performance for documentation, coding and reimbursement does allow hospitals to go beyond focused operational metrics to evaluate themselves in a broad industry context to determine whether they are in alignment with examples from other institutions.2

Given this background, specific strategies used to justify hospital support for the glycemic control will now be outlined.

B. REVENUE GENERATION THROUGH BILLING FOR CLINICAL SERVICES

Implementation of targeted BG control in the hospital provides opportunities for an increase in the provision of clinical consultative services for diabetes management. Physicians and allied healthcare providers can bill when they provide such care, and the revenues offset costs of salary, fringe benefits and other expenses.

CONCLUSION

Financial justification for support of a hospital based glycemic control team is challenging but possible, as has been shown by Newton5 and by DeSantis and Molitch.10 Various models may be used individually or in combination to make the case to hospital administration for salary support for team members. The models that may be helpful in this regard include: improved documentation opportunities; reduction in length of stay; reimbursement for direct clinical diabetes case management consultative services by physicians and NPs or PAs, and demonstration of improved resource utilization for the hyperglycemic patient managed by the hospital glycemic control team.

Implementation of targeted inpatient glycemic control by a multidisciplinary team in the hospital is a time‐intensive and labor‐intensive undertaking. A variety of business models may be applied including those in which the hospital provides financial support and those which will be self‐supporting through clinical billing revenues (Table 1). In practice, a combination of these strategies may be used.

In order to make the case to hospital administration for investment of financial support for glycemic control programs, it is necessary to develop a business plan that will justify return on investment. The following discussion is a composite of information from the published literature, personal communication with hospital glycemic control champions, and the author's experience developing, implementing, and assessing outcomes for a glycemic control task force charged with improving glucose control in the 7 hospital MedStar Health system from which more than 45,000 patients are discharged annually with a diagnosis of diabetes.

The principles for making the business case for support of a glycemic control team are the same as those applied in other hospital‐based programs. While the clinical argument for a new process, resource, or staff member may be sound, the business plan will also be analyzed from nonclinical perspectives, with attention to its fiscal and operational feasibility. It is therefore important to involve hospital administration, operations, and finance representatives early, in order to obtain their support and address concerns early that would otherwise weaken the request. The information provided in this article is intended to provide practical guidance for developing a plan that is realistic and tailored to the needs of the individual institution.

A. HOSPITAL‐SUPPORTED MODELS

The business case for hospital support for the glycemic control team is based on opportunities to improve revenue through accurate documentation and coding, reduction in length of stay, and optimization of resource utilization through reduction in morbidity and mortality (cost aversion).

In order to understand opportunities for improved revenue, it is necessary to understand how hospitals are reimbursed for inpatient care. Medical record documentation is reviewed by hospital coding personnel who apply strict guidelines and ICD‐9‐CM nomenclature to establish the diagnoses and procedures for each case. The ICD‐9‐CM is a numerical coding scheme of more than 13,000 diagnoses and 5,000 procedures. The principal and secondary diagnoses and procedures are grouped into a Diagnosis Related Group (DRG) code. In most states, CMS (Medicare) reimburses hospitals a flat rate based on the DRG code assigned to each inpatient case. CMS calculates a specific DRG weight for each DRG code. The DRG weight is a number such as 0.895 or 1.24, which reflects the acuity of the patient assigned to a particular DRG code and expected resource utilization. The greater the weight, the greater the acuity and expected resource utilization. The overall Case Mix Index (CMI) is the simple average of the DRG weight for a population of inpatients. CMI indicates the relative severity of a patient population and is directly proportional to DRG payments. This index is valuable when making comparisons between hospitals or patient groups.

Each hospital is provided a single rate relative to a DRG weight of 1.0 which allows calculation of the expected revenue from CMS per case. The DRG payment for a Medicare patient is determined by multiplying the relative weight for the DRG by the hospital's blended rate: DRG PAYMENT = WEIGHT RATE. Each hospital's payment rate is defined by federal regulations and is updated annually to reflect inflation, technical adjustments, and budgetary constraints. There are separate rate calculations for large urban hospitals and other hospitals. There are also technical adjustments for local wage variations, teaching hospitals, and hospitals with a disproportionate share of indigent patients.1

Determination of allowable charges for inpatient care varies by location and payor. The State of Maryland, for example regulates hospital inpatient charges for all patients based on the CMI of each hospital. In this reimbursement system, the hospital must ensure that their total average charge per case is on par with their reported CMI, when compared to other hospitals. For non‐Medicare payors, reimbursement may also be based on a set DRG payment or a percentage of charges based on contractual stipulations. The business case will be based on the individual hospital's allowed charges.

Empirical studies in this area are lacking, perhaps in part because this is a sensitive data area. Publications tend to focus on potential rather than actual results. Profiling hospital improvement management performance for documentation, coding and reimbursement does allow hospitals to go beyond focused operational metrics to evaluate themselves in a broad industry context to determine whether they are in alignment with examples from other institutions.2

Given this background, specific strategies used to justify hospital support for the glycemic control will now be outlined.

B. REVENUE GENERATION THROUGH BILLING FOR CLINICAL SERVICES

Implementation of targeted BG control in the hospital provides opportunities for an increase in the provision of clinical consultative services for diabetes management. Physicians and allied healthcare providers can bill when they provide such care, and the revenues offset costs of salary, fringe benefits and other expenses.

CONCLUSION

Financial justification for support of a hospital based glycemic control team is challenging but possible, as has been shown by Newton5 and by DeSantis and Molitch.10 Various models may be used individually or in combination to make the case to hospital administration for salary support for team members. The models that may be helpful in this regard include: improved documentation opportunities; reduction in length of stay; reimbursement for direct clinical diabetes case management consultative services by physicians and NPs or PAs, and demonstration of improved resource utilization for the hyperglycemic patient managed by the hospital glycemic control team.

Data collection, analysis, and presentation are key to the success of any hospital glycemic control initiative. Such efforts enable the management team to track improvements in processes and outcomes, make necessary changes to their quality improvement efforts, justify the provision of necessary time and resources, and share their results with others. Reliable metrics for assessing glycemic control and frequency of hypoglycemia are essential to accomplish these tasks and to assess whether interventions result in more benefit than harm. Hypoglycemia metrics must be especially convincing because fear of hypoglycemia remains a major source of clinical inertia, impeding efforts to improve glucose control.

Currently, there are no official standards or guidelines for formulating metrics on the quality of inpatient glycemic control. This creates several problems. First, different metrics vary in their biases and in their responsiveness to change. Thus, use of a poor metric could lead to either a falsely positive or falsely negative impression that a quality improvement intervention is in fact improving glycemic control. Second, the proliferation of different measures and analytical plans in the research and quality improvement literature make it very difficult for hospitals to compare baseline performance, determine need for improvement, and understand which interventions may be most effective.

A related article in this supplement provides the rationale for improved inpatient glycemic control. That article argues that the current state of inpatient glycemic control, with the frequent occurrence of severe hyperglycemia and irrational insulin ordering, cannot be considered acceptable, especially given the large body of data (albeit largely observational) linking hyperglycemia to negative patient outcomes. However, regardless of whether one is an advocate or skeptic of tighter glucose control in the intensive care unit (ICU) and especially the non‐ICU setting, there is no question that standardized, valid, and reliable metrics are needed to compare efforts to improve glycemic control, better understand whether such control actually improves patient care, and closely monitor patient safety.

This article provides a summary of practical suggestions to assess glycemic control, insulin use patterns, and safety (hypoglycemia and severe hyperglycemia). In particular, we discuss the pros and cons of various measurement choices. We conclude with a tiered summary of recommendations for practical metrics that we hope will be useful to individual improvement teams. This article is not a consensus statement but rather a starting place that we hope will begin to standardize measurement across institutions and advance the dialogue on this subject. To more definitely address this problem, we call on the American Association of Clinical Endocrinologists (AACE), American Diabetes Association (ADA), Society of Hospital Medicine (SHM), and others to agree on consensus standards regarding metrics for the quality of inpatient glycemic control.

MEASURING GLYCEMIC CONTROL: GLUCOMETRICS

Glucometrics may be defined as the systematic analysis of blood glucose (BG) dataa phrase initially coined specifically for the inpatient setting. There are numerous ways to do these analyses, depending on which patients and glucose values are considered, the definitions used for hypoglycemia and hyperglycemia, the unit of measurement (eg, patient, patient‐day, individual glucose value), and the measure of control (eg, mean, median, percent of glucose readings within a certain range). We consider each of these dimensions in turn.

APPROACHES TO ANALYSIS: RUN CHARTS

Most conventional clinical trials hold interventions fixed for a period of time and compare results with and without the intervention. For quality improvement studies, this is still a valid way to proceed, especially if studied as a randomized controlled trial. Such methods may be preferred when the clinical question is Does this type of intervention work in general? and the desired output is publication in peer‐reviewed journals so that others can learn about and adopt the intervention to their own institution. A before and after study with a similar analytic approach may also be valid, although concerns about temporal trends and cointerventions potentially compromise the validity of such studies. This approach again assumes that an intervention is held fixed over time such that it is clear what patients received during each time period.

If the desired result is improvement at a given institution (the question is Did we improve care?) then it may be preferable to present results over time using run‐charts. In a run chart, the x‐axis is time and the y‐axis the desired metric, such as patient‐day weighted mean glucose. Points in time when interventions were introduced or modified can be highlighted. Run charts have several advantages over before‐and‐after summaries: they do not require interventions remaining fixed and are more compatible with continuous quality improvement methods, it is easier to see the effect of different aspects of the interventions as they occur, one can get a quicker picture of whether something is working, and it is easier to separate out the impact of the intervention from secular trends. Finally, the use of run charts does not imply the absence of statistical rigor. Run charts with statistical process control (SPC) limits5 can easily convey when the observed time trend is unlikely to be due to chance using prespecified P values. (A full discussion of SPC and other methods to study quality improvement interventions is beyond the scope of this article.)

ASSESSING PATTERNS OF INSULIN USE AND ORDER SET UTILIZATION

Besides measuring the impact of quality improvement interventions on glucose control, it is important to measure processes such as proper insulin use. As mentioned in other articles in this supplement, processes are much more sensitive to change than outcomes. Failure to change processes should lead one to make changes to the intervention.

OTHER CONSIDERATIONS AND METRICS

Examples of other metrics that can be used to track the success of quality improvement efforts include:

• 1

  Glucose measurement within 8 hours of hospital admission.

• 2

  Glycated hemoglobin (A1C) measurement obtained or available within 30 days of admission to help guide inpatient and especially discharge management.

• 3

  Appropriate glucose testing in patients with diabetes or hyperglycemia (eg, 4 times per day in patients not on insulin infusion protocols, at least until 24 hours of euglycemia is documented).

• 4

  The percentage of patients on insulin with on‐time tray delivery.

• 5

  The timing of subcutaneous insulin administration in relation to glucose testing and nutrition delivery.

• 6

  Documentation of carbohydrate intake among patients who are eating.

• 7

  Satisfaction of physicians and nurses with order sets or protocols, using standard surveys.

• 8

  Physician and nurse knowledge, attitudes, and beliefs about insulin administration, fear of hypoglycemia, treatment of hypoglycemia, and glycemic control in the hospital.

• 9

  Patient satisfaction with their diabetes care in the hospital, including the education they received.

• 10

  Nursing and physician education/certification in insulin prescribing, insulin administration, and other diabetes care issues.

• 11

  Patient outcomes strongly associated with glycemic control, (eg, surgical wound infections, ICU LOS, catheter‐related bloodstream infections).

• 12

  Appropriate treatment and documentation of hypoglycemia (eg, in accordance with hospital policy).

• 13

  Documentation of severe hypoglycemic events through the hospital's adverse events reporting system (these may actually increase as change comes to the organization and as clinical personnel are more attuned to glycemic control).

• 14

  Root causes of hypoglycemic events, which can be used to understand and prevent future events.

• 15

  Appropriate transitions from IV to SC insulin regimens, (eg, starting basal insulin prior to discontinuing infusion in patients who have been on an insulin infusion of at least 2 units/hour or who have a known diagnosis of diabetes or A1C >7).

(Survey instruments and other measurement tools are available from the authors upon request.)

SHM GLYCEMIC CONTROL TASK FORCE SUMMARY RECOMMENDATIONS

The SHM Glycemic Control Task Force is working to develop standardized measures of inpatient glucose control and related indicators to track progress of hospital glycemic control initiatives (see the introduction to this supplement for a description of the charge and membership of this task force). The goals of the Task Force's metrics recommendations (Table 1) are several‐fold: (1) create a set of measurements that are complete but not overly burdensome; (2) create realistic measures that can be applied to institutions with different data management capabilities; and (3) allow for comparison across institutions for benchmarking purposes, evaluation of quality improvement projects, and reporting of results for formal research studies in this field.

For each domain of glycemic management (glycemic control, safety, and insulin use), the task force chose a set of best measures. They are presented as two tiers of measurement standards, depending on the capabilities of the institution and the planned uses of the data. Tier 1 includes measures that, although they do take time and resources to collect, are feasible for most institutions. Tier 2 measures are recommended for hospitals with easy manipulation of electronic sources of data and for reporting quality‐of‐care measures for widespread publication, that is, in the context of a research study. It should be emphasized that these recommendations are only meant as a guide: the actual measures chosen should meet the needs and capabilities of each institution.

We recognize that few data support the recommendations made by this task force, that such data are needed, and that the field of data collection and analysis for hospital glycemic management is rapidly evolving. The hope is to begin the standardization process, promote dialogue in this field, and eventually reach a consensus in collaboration with the ADA, AACE, and other pertinent stakeholders.

CONCLUSIONS

Like the field of inpatient glycemic management itself, the field of devising metrics to measure the quality of inpatient glycemic control is also in its infancy and quickly evolving. One should not be paralyzed by the lack of consensus regarding measurementthe important point is to pick a few complementary metrics and begin the process. The table of recommendations can hopefully serve as a starting point for many institutions, with a focus on efficacy (glycemic control), safety (hypoglycemia), and process (insulin use patterns). As your institution gains experience with measurement and the field evolves, your metrics will likely change. We recommend keeping all process and outcome data in its raw form so that it can be summarized in different ways over time. It is also important not to wait for the perfect data collection tool before beginning to analyze data: sampling and paper processes are acceptable if automated data collection is not yet possible. Eventually, blood glucose meter readings should be downloaded into a central database that interfaces with hospital data repositories so data can be analyzed in conjunction with patient, service, and unit‐level information. Only with a rigorous measurement process can institutions hope to know whether their changes are resulting in improved care for patients.

Data collection, analysis, and presentation are key to the success of any hospital glycemic control initiative. Such efforts enable the management team to track improvements in processes and outcomes, make necessary changes to their quality improvement efforts, justify the provision of necessary time and resources, and share their results with others. Reliable metrics for assessing glycemic control and frequency of hypoglycemia are essential to accomplish these tasks and to assess whether interventions result in more benefit than harm. Hypoglycemia metrics must be especially convincing because fear of hypoglycemia remains a major source of clinical inertia, impeding efforts to improve glucose control.

Currently, there are no official standards or guidelines for formulating metrics on the quality of inpatient glycemic control. This creates several problems. First, different metrics vary in their biases and in their responsiveness to change. Thus, use of a poor metric could lead to either a falsely positive or falsely negative impression that a quality improvement intervention is in fact improving glycemic control. Second, the proliferation of different measures and analytical plans in the research and quality improvement literature make it very difficult for hospitals to compare baseline performance, determine need for improvement, and understand which interventions may be most effective.

A related article in this supplement provides the rationale for improved inpatient glycemic control. That article argues that the current state of inpatient glycemic control, with the frequent occurrence of severe hyperglycemia and irrational insulin ordering, cannot be considered acceptable, especially given the large body of data (albeit largely observational) linking hyperglycemia to negative patient outcomes. However, regardless of whether one is an advocate or skeptic of tighter glucose control in the intensive care unit (ICU) and especially the non‐ICU setting, there is no question that standardized, valid, and reliable metrics are needed to compare efforts to improve glycemic control, better understand whether such control actually improves patient care, and closely monitor patient safety.

This article provides a summary of practical suggestions to assess glycemic control, insulin use patterns, and safety (hypoglycemia and severe hyperglycemia). In particular, we discuss the pros and cons of various measurement choices. We conclude with a tiered summary of recommendations for practical metrics that we hope will be useful to individual improvement teams. This article is not a consensus statement but rather a starting place that we hope will begin to standardize measurement across institutions and advance the dialogue on this subject. To more definitely address this problem, we call on the American Association of Clinical Endocrinologists (AACE), American Diabetes Association (ADA), Society of Hospital Medicine (SHM), and others to agree on consensus standards regarding metrics for the quality of inpatient glycemic control.

MEASURING GLYCEMIC CONTROL: GLUCOMETRICS

Glucometrics may be defined as the systematic analysis of blood glucose (BG) dataa phrase initially coined specifically for the inpatient setting. There are numerous ways to do these analyses, depending on which patients and glucose values are considered, the definitions used for hypoglycemia and hyperglycemia, the unit of measurement (eg, patient, patient‐day, individual glucose value), and the measure of control (eg, mean, median, percent of glucose readings within a certain range). We consider each of these dimensions in turn.

APPROACHES TO ANALYSIS: RUN CHARTS

Most conventional clinical trials hold interventions fixed for a period of time and compare results with and without the intervention. For quality improvement studies, this is still a valid way to proceed, especially if studied as a randomized controlled trial. Such methods may be preferred when the clinical question is Does this type of intervention work in general? and the desired output is publication in peer‐reviewed journals so that others can learn about and adopt the intervention to their own institution. A before and after study with a similar analytic approach may also be valid, although concerns about temporal trends and cointerventions potentially compromise the validity of such studies. This approach again assumes that an intervention is held fixed over time such that it is clear what patients received during each time period.

If the desired result is improvement at a given institution (the question is Did we improve care?) then it may be preferable to present results over time using run‐charts. In a run chart, the x‐axis is time and the y‐axis the desired metric, such as patient‐day weighted mean glucose. Points in time when interventions were introduced or modified can be highlighted. Run charts have several advantages over before‐and‐after summaries: they do not require interventions remaining fixed and are more compatible with continuous quality improvement methods, it is easier to see the effect of different aspects of the interventions as they occur, one can get a quicker picture of whether something is working, and it is easier to separate out the impact of the intervention from secular trends. Finally, the use of run charts does not imply the absence of statistical rigor. Run charts with statistical process control (SPC) limits5 can easily convey when the observed time trend is unlikely to be due to chance using prespecified P values. (A full discussion of SPC and other methods to study quality improvement interventions is beyond the scope of this article.)

ASSESSING PATTERNS OF INSULIN USE AND ORDER SET UTILIZATION

Besides measuring the impact of quality improvement interventions on glucose control, it is important to measure processes such as proper insulin use. As mentioned in other articles in this supplement, processes are much more sensitive to change than outcomes. Failure to change processes should lead one to make changes to the intervention.

OTHER CONSIDERATIONS AND METRICS

Examples of other metrics that can be used to track the success of quality improvement efforts include:

• 1

  Glucose measurement within 8 hours of hospital admission.

• 2

  Glycated hemoglobin (A1C) measurement obtained or available within 30 days of admission to help guide inpatient and especially discharge management.

• 3

  Appropriate glucose testing in patients with diabetes or hyperglycemia (eg, 4 times per day in patients not on insulin infusion protocols, at least until 24 hours of euglycemia is documented).

• 4

  The percentage of patients on insulin with on‐time tray delivery.

• 5

  The timing of subcutaneous insulin administration in relation to glucose testing and nutrition delivery.

• 6

  Documentation of carbohydrate intake among patients who are eating.

• 7

  Satisfaction of physicians and nurses with order sets or protocols, using standard surveys.

• 8

  Physician and nurse knowledge, attitudes, and beliefs about insulin administration, fear of hypoglycemia, treatment of hypoglycemia, and glycemic control in the hospital.

• 9

  Patient satisfaction with their diabetes care in the hospital, including the education they received.

• 10

  Nursing and physician education/certification in insulin prescribing, insulin administration, and other diabetes care issues.

• 11

  Patient outcomes strongly associated with glycemic control, (eg, surgical wound infections, ICU LOS, catheter‐related bloodstream infections).

• 12

  Appropriate treatment and documentation of hypoglycemia (eg, in accordance with hospital policy).

• 13

  Documentation of severe hypoglycemic events through the hospital's adverse events reporting system (these may actually increase as change comes to the organization and as clinical personnel are more attuned to glycemic control).

• 14

  Root causes of hypoglycemic events, which can be used to understand and prevent future events.

• 15

  Appropriate transitions from IV to SC insulin regimens, (eg, starting basal insulin prior to discontinuing infusion in patients who have been on an insulin infusion of at least 2 units/hour or who have a known diagnosis of diabetes or A1C >7).

(Survey instruments and other measurement tools are available from the authors upon request.)

SHM GLYCEMIC CONTROL TASK FORCE SUMMARY RECOMMENDATIONS

The SHM Glycemic Control Task Force is working to develop standardized measures of inpatient glucose control and related indicators to track progress of hospital glycemic control initiatives (see the introduction to this supplement for a description of the charge and membership of this task force). The goals of the Task Force's metrics recommendations (Table 1) are several‐fold: (1) create a set of measurements that are complete but not overly burdensome; (2) create realistic measures that can be applied to institutions with different data management capabilities; and (3) allow for comparison across institutions for benchmarking purposes, evaluation of quality improvement projects, and reporting of results for formal research studies in this field.

For each domain of glycemic management (glycemic control, safety, and insulin use), the task force chose a set of best measures. They are presented as two tiers of measurement standards, depending on the capabilities of the institution and the planned uses of the data. Tier 1 includes measures that, although they do take time and resources to collect, are feasible for most institutions. Tier 2 measures are recommended for hospitals with easy manipulation of electronic sources of data and for reporting quality‐of‐care measures for widespread publication, that is, in the context of a research study. It should be emphasized that these recommendations are only meant as a guide: the actual measures chosen should meet the needs and capabilities of each institution.

We recognize that few data support the recommendations made by this task force, that such data are needed, and that the field of data collection and analysis for hospital glycemic management is rapidly evolving. The hope is to begin the standardization process, promote dialogue in this field, and eventually reach a consensus in collaboration with the ADA, AACE, and other pertinent stakeholders.

CONCLUSIONS

Like the field of inpatient glycemic management itself, the field of devising metrics to measure the quality of inpatient glycemic control is also in its infancy and quickly evolving. One should not be paralyzed by the lack of consensus regarding measurementthe important point is to pick a few complementary metrics and begin the process. The table of recommendations can hopefully serve as a starting point for many institutions, with a focus on efficacy (glycemic control), safety (hypoglycemia), and process (insulin use patterns). As your institution gains experience with measurement and the field evolves, your metrics will likely change. We recommend keeping all process and outcome data in its raw form so that it can be summarized in different ways over time. It is also important not to wait for the perfect data collection tool before beginning to analyze data: sampling and paper processes are acceptable if automated data collection is not yet possible. Eventually, blood glucose meter readings should be downloaded into a central database that interfaces with hospital data repositories so data can be analyzed in conjunction with patient, service, and unit‐level information. Only with a rigorous measurement process can institutions hope to know whether their changes are resulting in improved care for patients.

Data collection, analysis, and presentation are key to the success of any hospital glycemic control initiative. Such efforts enable the management team to track improvements in processes and outcomes, make necessary changes to their quality improvement efforts, justify the provision of necessary time and resources, and share their results with others. Reliable metrics for assessing glycemic control and frequency of hypoglycemia are essential to accomplish these tasks and to assess whether interventions result in more benefit than harm. Hypoglycemia metrics must be especially convincing because fear of hypoglycemia remains a major source of clinical inertia, impeding efforts to improve glucose control.

Currently, there are no official standards or guidelines for formulating metrics on the quality of inpatient glycemic control. This creates several problems. First, different metrics vary in their biases and in their responsiveness to change. Thus, use of a poor metric could lead to either a falsely positive or falsely negative impression that a quality improvement intervention is in fact improving glycemic control. Second, the proliferation of different measures and analytical plans in the research and quality improvement literature make it very difficult for hospitals to compare baseline performance, determine need for improvement, and understand which interventions may be most effective.

A related article in this supplement provides the rationale for improved inpatient glycemic control. That article argues that the current state of inpatient glycemic control, with the frequent occurrence of severe hyperglycemia and irrational insulin ordering, cannot be considered acceptable, especially given the large body of data (albeit largely observational) linking hyperglycemia to negative patient outcomes. However, regardless of whether one is an advocate or skeptic of tighter glucose control in the intensive care unit (ICU) and especially the non‐ICU setting, there is no question that standardized, valid, and reliable metrics are needed to compare efforts to improve glycemic control, better understand whether such control actually improves patient care, and closely monitor patient safety.

This article provides a summary of practical suggestions to assess glycemic control, insulin use patterns, and safety (hypoglycemia and severe hyperglycemia). In particular, we discuss the pros and cons of various measurement choices. We conclude with a tiered summary of recommendations for practical metrics that we hope will be useful to individual improvement teams. This article is not a consensus statement but rather a starting place that we hope will begin to standardize measurement across institutions and advance the dialogue on this subject. To more definitely address this problem, we call on the American Association of Clinical Endocrinologists (AACE), American Diabetes Association (ADA), Society of Hospital Medicine (SHM), and others to agree on consensus standards regarding metrics for the quality of inpatient glycemic control.

MEASURING GLYCEMIC CONTROL: GLUCOMETRICS

Glucometrics may be defined as the systematic analysis of blood glucose (BG) dataa phrase initially coined specifically for the inpatient setting. There are numerous ways to do these analyses, depending on which patients and glucose values are considered, the definitions used for hypoglycemia and hyperglycemia, the unit of measurement (eg, patient, patient‐day, individual glucose value), and the measure of control (eg, mean, median, percent of glucose readings within a certain range). We consider each of these dimensions in turn.

APPROACHES TO ANALYSIS: RUN CHARTS

Most conventional clinical trials hold interventions fixed for a period of time and compare results with and without the intervention. For quality improvement studies, this is still a valid way to proceed, especially if studied as a randomized controlled trial. Such methods may be preferred when the clinical question is Does this type of intervention work in general? and the desired output is publication in peer‐reviewed journals so that others can learn about and adopt the intervention to their own institution. A before and after study with a similar analytic approach may also be valid, although concerns about temporal trends and cointerventions potentially compromise the validity of such studies. This approach again assumes that an intervention is held fixed over time such that it is clear what patients received during each time period.

If the desired result is improvement at a given institution (the question is Did we improve care?) then it may be preferable to present results over time using run‐charts. In a run chart, the x‐axis is time and the y‐axis the desired metric, such as patient‐day weighted mean glucose. Points in time when interventions were introduced or modified can be highlighted. Run charts have several advantages over before‐and‐after summaries: they do not require interventions remaining fixed and are more compatible with continuous quality improvement methods, it is easier to see the effect of different aspects of the interventions as they occur, one can get a quicker picture of whether something is working, and it is easier to separate out the impact of the intervention from secular trends. Finally, the use of run charts does not imply the absence of statistical rigor. Run charts with statistical process control (SPC) limits5 can easily convey when the observed time trend is unlikely to be due to chance using prespecified P values. (A full discussion of SPC and other methods to study quality improvement interventions is beyond the scope of this article.)

ASSESSING PATTERNS OF INSULIN USE AND ORDER SET UTILIZATION

Besides measuring the impact of quality improvement interventions on glucose control, it is important to measure processes such as proper insulin use. As mentioned in other articles in this supplement, processes are much more sensitive to change than outcomes. Failure to change processes should lead one to make changes to the intervention.

OTHER CONSIDERATIONS AND METRICS

Examples of other metrics that can be used to track the success of quality improvement efforts include:

• 1

  Glucose measurement within 8 hours of hospital admission.

• 2

  Glycated hemoglobin (A1C) measurement obtained or available within 30 days of admission to help guide inpatient and especially discharge management.

• 3

  Appropriate glucose testing in patients with diabetes or hyperglycemia (eg, 4 times per day in patients not on insulin infusion protocols, at least until 24 hours of euglycemia is documented).

• 4

  The percentage of patients on insulin with on‐time tray delivery.

• 5

  The timing of subcutaneous insulin administration in relation to glucose testing and nutrition delivery.

• 6

  Documentation of carbohydrate intake among patients who are eating.

• 7

  Satisfaction of physicians and nurses with order sets or protocols, using standard surveys.

• 8

  Physician and nurse knowledge, attitudes, and beliefs about insulin administration, fear of hypoglycemia, treatment of hypoglycemia, and glycemic control in the hospital.

• 9

  Patient satisfaction with their diabetes care in the hospital, including the education they received.

• 10

  Nursing and physician education/certification in insulin prescribing, insulin administration, and other diabetes care issues.

• 11

  Patient outcomes strongly associated with glycemic control, (eg, surgical wound infections, ICU LOS, catheter‐related bloodstream infections).

• 12

  Appropriate treatment and documentation of hypoglycemia (eg, in accordance with hospital policy).

• 13

  Documentation of severe hypoglycemic events through the hospital's adverse events reporting system (these may actually increase as change comes to the organization and as clinical personnel are more attuned to glycemic control).

• 14

  Root causes of hypoglycemic events, which can be used to understand and prevent future events.

• 15

  Appropriate transitions from IV to SC insulin regimens, (eg, starting basal insulin prior to discontinuing infusion in patients who have been on an insulin infusion of at least 2 units/hour or who have a known diagnosis of diabetes or A1C >7).

(Survey instruments and other measurement tools are available from the authors upon request.)

SHM GLYCEMIC CONTROL TASK FORCE SUMMARY RECOMMENDATIONS

The SHM Glycemic Control Task Force is working to develop standardized measures of inpatient glucose control and related indicators to track progress of hospital glycemic control initiatives (see the introduction to this supplement for a description of the charge and membership of this task force). The goals of the Task Force's metrics recommendations (Table 1) are several‐fold: (1) create a set of measurements that are complete but not overly burdensome; (2) create realistic measures that can be applied to institutions with different data management capabilities; and (3) allow for comparison across institutions for benchmarking purposes, evaluation of quality improvement projects, and reporting of results for formal research studies in this field.

For each domain of glycemic management (glycemic control, safety, and insulin use), the task force chose a set of best measures. They are presented as two tiers of measurement standards, depending on the capabilities of the institution and the planned uses of the data. Tier 1 includes measures that, although they do take time and resources to collect, are feasible for most institutions. Tier 2 measures are recommended for hospitals with easy manipulation of electronic sources of data and for reporting quality‐of‐care measures for widespread publication, that is, in the context of a research study. It should be emphasized that these recommendations are only meant as a guide: the actual measures chosen should meet the needs and capabilities of each institution.

We recognize that few data support the recommendations made by this task force, that such data are needed, and that the field of data collection and analysis for hospital glycemic management is rapidly evolving. The hope is to begin the standardization process, promote dialogue in this field, and eventually reach a consensus in collaboration with the ADA, AACE, and other pertinent stakeholders.

CONCLUSIONS

Like the field of inpatient glycemic management itself, the field of devising metrics to measure the quality of inpatient glycemic control is also in its infancy and quickly evolving. One should not be paralyzed by the lack of consensus regarding measurementthe important point is to pick a few complementary metrics and begin the process. The table of recommendations can hopefully serve as a starting point for many institutions, with a focus on efficacy (glycemic control), safety (hypoglycemia), and process (insulin use patterns). As your institution gains experience with measurement and the field evolves, your metrics will likely change. We recommend keeping all process and outcome data in its raw form so that it can be summarized in different ways over time. It is also important not to wait for the perfect data collection tool before beginning to analyze data: sampling and paper processes are acceptable if automated data collection is not yet possible. Eventually, blood glucose meter readings should be downloaded into a central database that interfaces with hospital data repositories so data can be analyzed in conjunction with patient, service, and unit‐level information. Only with a rigorous measurement process can institutions hope to know whether their changes are resulting in improved care for patients.

The articles on these pages represent the culmination of 3 years of effort by the Society of Hospital Medicine (SHM) Glycemic Control Task Force. In this brief introduction, we share a few insights and comments about this multidisciplinary collaborative effort to address the care of inpatients with hyperglycemia.

The SHM Glycemic Control Task Force was assembled in 2005, with the intent of improving the care of inpatients with diabetes. We wished to provide hospitalists and quality improvement teams with an understanding of the best practices to achieve safe glycemic control in the hospital. Additionally, this task force sought to identify tools and strategies to obtain improved communication, medication safety, education, and other aspects of care. A distinguished panel of experts attended their inaugural meeting in Chicago, Illinois, in October 2005, including hospitalists, endocrinologists, nurses, case managers, diabetes educators, and pharmacists. A roster of the individuals and organizations is given in the Appendix.

Many members of the SHM Glycemic Control Task Force also participated in the Call to Action consensus conference1 hosted by the American Association of Clinical Endocrinologists (AACE) and the American Diabetes Association (ADA) in January 2006. Both groups identified several barriers to improvement, and methods to overcome these barriers were summarized in this quote from the Consensus Conference,

Successful implementation of a program to improve glycemic control in the inpatient setting should include the following components:

• 1

  An appropriate level of administrative support.

• 2

  Formation of a multidisciplinary steering committee to drive the development of initiatives.

• 3

  Assessment of current processes, quality of care, and barriers to practice change.

• 4

  Development and implementation of interventions including standardized order sets, protocols, policies, and algorithms with associated educational programs.

• 5

  Metrics for evaluation.

Both groups also called for a web‐based compendium of tested tools and strategies to assist local improvement teams.

After countless hours of development and revision by the SHM Glycemic Task Force and the Resource Room team, such a compendium addressing all of these components was launched on the SHM web site in the form of the SHM Glycemic Control Resource Room.2 A comprehensive implementation guide3 is available for downloading free of charge, and serves as the centerpiece of the Resource Room. Subsequently, this comprehensive but somewhat sprawling implementation guide evolved into these more sophisticated and concise articles.410 The topics include a review of the rationale for improving inpatient glycemic control,4 an important call for standardizing the metrics of glycemic control,9 subcutaneous insulin regimens and order sets,5, 6 insulin infusion protocols,7 transitions of care,8 and the business case for glycemic control.10 It has been a long but rewarding and educational journey, drawing on the collective experience from dozens of institutions in all kinds of inpatient care settings. A few key points and insights seem worth sharing.

THE IMPROVEMENT EFFORT IS NOT JUST ABOUT REACHING A GLYCEMIC TARGET

The term glycemic control team and the label for the SHM Glycemic Control Task Force itself are somewhat misnomers. Task Force members agree that desirable institutional glycemic target ranges should be established, but many among us believe the glycemic targets endorsed by national guidelines (ref ADA and AACE guidelines)11, 12 are too stringent. Furthermore, we believe that achieving glycemic control is just one small part of the needed improvement efforts. Uncontrolled hyperglycemia is common, potentially dangerous, and largely preventable with safe and proven methodsbut so are the iatrogenic hypoglycemia episodes, substandard education, poor communication, lack of care coordination, and inadequate monitoring that typify care of the hyperglycemic inpatient. We address all of these issues and urge the adoption of this broader perspective.

THE EVIDENCE IS INCOMPLETEBUT ACTION IS REQUIRED

We acknowledge gaps and inconsistencies in the literature surrounding inpatient diabetes management and the controversy around tight glycemic control. In many cases, high level evidence is not available to guide the formulation of protocols, order sets, or other improvement tools. We are all struck by how pervasive the lack of evidence is. What is the best metric for inpatient glycemic control or hypoglycemia? What is the best regimen for a patient on continuous tube feedings? Which insulin infusion protocol is superior in reaching and maintaining a glycemic target range?

Rather than make no recommendations or accept negative inertia on the basis of less than perfect evidence, we make recommendations based on the best evidence available. When we make recommendations based on consensus opinion or the collective experience from dozens of medical centers, rather than randomized trials, we have made every effort to make this clear in the text of the articles. In our view, incomplete evidence is not an adequate excuse to persist in the unacceptable status quo, clinging on to methods (such as sliding scale insulin regimens) that have been shown to be ineffective and potentially dangerous.1315

COLLABORATION PAYS DIVIDENDS

It takes a multidisciplinary approach to make substantial improvement in glycemic control of hospitalized patients. By the same token, it is unlikely that any one group can advance the national agenda for improved care as well as a multidisciplinary coordinated effort. Team members, especially the endocrinologists and hospitalists, collaborated skillfully throughout this effort. The hospitalists learned a tremendous amount from the expertise, insight, and mastery of the literature, offered by the endocrinology members, whereas the endocrinologists appreciated the front line expertise and practical quality improvement approach of the hospitalist members. This collaboration serves as a model for making guidelines and best practices become more of a practical reality for a variety of important clinical problems. Hospitalists can partner with and learn from a variety of other disciplines, while they assist these disciplines on effective improvement and implementation efforts. On a more personal note, this work has fostered mutual respect, friendship, and career long collaborative opportunities. The potential for these same opportunities with nursing, pharmacy, and all medical and surgical fields seems compelling and exciting.

THERE'S MORE!

By the time this is published, these articles will be integrated into the third iteration of the SHM Glycemic Control Resource Room. This online resource has already undergone 2 major revisions since its inception just a few years ago, reflecting SHM's dedication to the continuous improvement of the products and services that it offers. The Glycemic Control Implementation Guide and Resource Room will continue to be a work in progress. We highly encourage and welcome constructive criticism and feedback via E‐mail to [email protected]. The resource room contains a wealth of tools, slide shows, literature reviews, and links, in addition to the core articles published in this Supplement.

NEXT STEPS

More research and demonstration projects are obviously needed in this field. Local collaborative activities have sprung up in several cities and regions, as well as Glycemic Control Champions courses. A longitudinal mentoring program (similar to the SHM Venous Thromboembolism Prevention collaborative) would undoubtedly be beneficial, and may become available within the next year or so. These items and more will be promoted and posted in the resource room whenever possible.

Finally, the next step is up to you and the institutions in which you workyou have to decide, as individuals and institutions, if you believe the status quo is good enough. We believe that if you look, you'll find the care of our inpatients with diabetes and hyperglycemia disturbingly suboptimal, and hope that the work of the SHM Glycemic Control Task Force can help you rapidly improve on this state of affairs.

APPENDIX: GLYCEMIC CONTROL TASK FORCE

The Society of Hospital Medicine thanks all the members of the Glycemic Control Task Force, who encompass a distinguished panel of experts with representation from the AACE, ADA, ACP, and other organizations whose expertise was essential to the construction of the Glycemic Control Resource Room and the Implementation Guide for Glycemic Control and Prevention of Hypoglycemia.

The articles on these pages represent the culmination of 3 years of effort by the Society of Hospital Medicine (SHM) Glycemic Control Task Force. In this brief introduction, we share a few insights and comments about this multidisciplinary collaborative effort to address the care of inpatients with hyperglycemia.

The SHM Glycemic Control Task Force was assembled in 2005, with the intent of improving the care of inpatients with diabetes. We wished to provide hospitalists and quality improvement teams with an understanding of the best practices to achieve safe glycemic control in the hospital. Additionally, this task force sought to identify tools and strategies to obtain improved communication, medication safety, education, and other aspects of care. A distinguished panel of experts attended their inaugural meeting in Chicago, Illinois, in October 2005, including hospitalists, endocrinologists, nurses, case managers, diabetes educators, and pharmacists. A roster of the individuals and organizations is given in the Appendix.

Many members of the SHM Glycemic Control Task Force also participated in the Call to Action consensus conference1 hosted by the American Association of Clinical Endocrinologists (AACE) and the American Diabetes Association (ADA) in January 2006. Both groups identified several barriers to improvement, and methods to overcome these barriers were summarized in this quote from the Consensus Conference,

Successful implementation of a program to improve glycemic control in the inpatient setting should include the following components:

• 1

  An appropriate level of administrative support.

• 2

  Formation of a multidisciplinary steering committee to drive the development of initiatives.

• 3

  Assessment of current processes, quality of care, and barriers to practice change.

• 4

  Development and implementation of interventions including standardized order sets, protocols, policies, and algorithms with associated educational programs.

• 5

  Metrics for evaluation.

Both groups also called for a web‐based compendium of tested tools and strategies to assist local improvement teams.

After countless hours of development and revision by the SHM Glycemic Task Force and the Resource Room team, such a compendium addressing all of these components was launched on the SHM web site in the form of the SHM Glycemic Control Resource Room.2 A comprehensive implementation guide3 is available for downloading free of charge, and serves as the centerpiece of the Resource Room. Subsequently, this comprehensive but somewhat sprawling implementation guide evolved into these more sophisticated and concise articles.410 The topics include a review of the rationale for improving inpatient glycemic control,4 an important call for standardizing the metrics of glycemic control,9 subcutaneous insulin regimens and order sets,5, 6 insulin infusion protocols,7 transitions of care,8 and the business case for glycemic control.10 It has been a long but rewarding and educational journey, drawing on the collective experience from dozens of institutions in all kinds of inpatient care settings. A few key points and insights seem worth sharing.

THE IMPROVEMENT EFFORT IS NOT JUST ABOUT REACHING A GLYCEMIC TARGET

The term glycemic control team and the label for the SHM Glycemic Control Task Force itself are somewhat misnomers. Task Force members agree that desirable institutional glycemic target ranges should be established, but many among us believe the glycemic targets endorsed by national guidelines (ref ADA and AACE guidelines)11, 12 are too stringent. Furthermore, we believe that achieving glycemic control is just one small part of the needed improvement efforts. Uncontrolled hyperglycemia is common, potentially dangerous, and largely preventable with safe and proven methodsbut so are the iatrogenic hypoglycemia episodes, substandard education, poor communication, lack of care coordination, and inadequate monitoring that typify care of the hyperglycemic inpatient. We address all of these issues and urge the adoption of this broader perspective.

THE EVIDENCE IS INCOMPLETEBUT ACTION IS REQUIRED

We acknowledge gaps and inconsistencies in the literature surrounding inpatient diabetes management and the controversy around tight glycemic control. In many cases, high level evidence is not available to guide the formulation of protocols, order sets, or other improvement tools. We are all struck by how pervasive the lack of evidence is. What is the best metric for inpatient glycemic control or hypoglycemia? What is the best regimen for a patient on continuous tube feedings? Which insulin infusion protocol is superior in reaching and maintaining a glycemic target range?

Rather than make no recommendations or accept negative inertia on the basis of less than perfect evidence, we make recommendations based on the best evidence available. When we make recommendations based on consensus opinion or the collective experience from dozens of medical centers, rather than randomized trials, we have made every effort to make this clear in the text of the articles. In our view, incomplete evidence is not an adequate excuse to persist in the unacceptable status quo, clinging on to methods (such as sliding scale insulin regimens) that have been shown to be ineffective and potentially dangerous.1315

COLLABORATION PAYS DIVIDENDS

It takes a multidisciplinary approach to make substantial improvement in glycemic control of hospitalized patients. By the same token, it is unlikely that any one group can advance the national agenda for improved care as well as a multidisciplinary coordinated effort. Team members, especially the endocrinologists and hospitalists, collaborated skillfully throughout this effort. The hospitalists learned a tremendous amount from the expertise, insight, and mastery of the literature, offered by the endocrinology members, whereas the endocrinologists appreciated the front line expertise and practical quality improvement approach of the hospitalist members. This collaboration serves as a model for making guidelines and best practices become more of a practical reality for a variety of important clinical problems. Hospitalists can partner with and learn from a variety of other disciplines, while they assist these disciplines on effective improvement and implementation efforts. On a more personal note, this work has fostered mutual respect, friendship, and career long collaborative opportunities. The potential for these same opportunities with nursing, pharmacy, and all medical and surgical fields seems compelling and exciting.

THERE'S MORE!

By the time this is published, these articles will be integrated into the third iteration of the SHM Glycemic Control Resource Room. This online resource has already undergone 2 major revisions since its inception just a few years ago, reflecting SHM's dedication to the continuous improvement of the products and services that it offers. The Glycemic Control Implementation Guide and Resource Room will continue to be a work in progress. We highly encourage and welcome constructive criticism and feedback via E‐mail to [email protected]. The resource room contains a wealth of tools, slide shows, literature reviews, and links, in addition to the core articles published in this Supplement.

NEXT STEPS

More research and demonstration projects are obviously needed in this field. Local collaborative activities have sprung up in several cities and regions, as well as Glycemic Control Champions courses. A longitudinal mentoring program (similar to the SHM Venous Thromboembolism Prevention collaborative) would undoubtedly be beneficial, and may become available within the next year or so. These items and more will be promoted and posted in the resource room whenever possible.

Finally, the next step is up to you and the institutions in which you workyou have to decide, as individuals and institutions, if you believe the status quo is good enough. We believe that if you look, you'll find the care of our inpatients with diabetes and hyperglycemia disturbingly suboptimal, and hope that the work of the SHM Glycemic Control Task Force can help you rapidly improve on this state of affairs.

APPENDIX: GLYCEMIC CONTROL TASK FORCE

The Society of Hospital Medicine thanks all the members of the Glycemic Control Task Force, who encompass a distinguished panel of experts with representation from the AACE, ADA, ACP, and other organizations whose expertise was essential to the construction of the Glycemic Control Resource Room and the Implementation Guide for Glycemic Control and Prevention of Hypoglycemia.

The articles on these pages represent the culmination of 3 years of effort by the Society of Hospital Medicine (SHM) Glycemic Control Task Force. In this brief introduction, we share a few insights and comments about this multidisciplinary collaborative effort to address the care of inpatients with hyperglycemia.

The SHM Glycemic Control Task Force was assembled in 2005, with the intent of improving the care of inpatients with diabetes. We wished to provide hospitalists and quality improvement teams with an understanding of the best practices to achieve safe glycemic control in the hospital. Additionally, this task force sought to identify tools and strategies to obtain improved communication, medication safety, education, and other aspects of care. A distinguished panel of experts attended their inaugural meeting in Chicago, Illinois, in October 2005, including hospitalists, endocrinologists, nurses, case managers, diabetes educators, and pharmacists. A roster of the individuals and organizations is given in the Appendix.

Many members of the SHM Glycemic Control Task Force also participated in the Call to Action consensus conference1 hosted by the American Association of Clinical Endocrinologists (AACE) and the American Diabetes Association (ADA) in January 2006. Both groups identified several barriers to improvement, and methods to overcome these barriers were summarized in this quote from the Consensus Conference,

Successful implementation of a program to improve glycemic control in the inpatient setting should include the following components:

• 1

  An appropriate level of administrative support.

• 2

  Formation of a multidisciplinary steering committee to drive the development of initiatives.

• 3

  Assessment of current processes, quality of care, and barriers to practice change.

• 4

  Development and implementation of interventions including standardized order sets, protocols, policies, and algorithms with associated educational programs.

• 5

  Metrics for evaluation.

Both groups also called for a web‐based compendium of tested tools and strategies to assist local improvement teams.

After countless hours of development and revision by the SHM Glycemic Task Force and the Resource Room team, such a compendium addressing all of these components was launched on the SHM web site in the form of the SHM Glycemic Control Resource Room.2 A comprehensive implementation guide3 is available for downloading free of charge, and serves as the centerpiece of the Resource Room. Subsequently, this comprehensive but somewhat sprawling implementation guide evolved into these more sophisticated and concise articles.410 The topics include a review of the rationale for improving inpatient glycemic control,4 an important call for standardizing the metrics of glycemic control,9 subcutaneous insulin regimens and order sets,5, 6 insulin infusion protocols,7 transitions of care,8 and the business case for glycemic control.10 It has been a long but rewarding and educational journey, drawing on the collective experience from dozens of institutions in all kinds of inpatient care settings. A few key points and insights seem worth sharing.

THE IMPROVEMENT EFFORT IS NOT JUST ABOUT REACHING A GLYCEMIC TARGET

The term glycemic control team and the label for the SHM Glycemic Control Task Force itself are somewhat misnomers. Task Force members agree that desirable institutional glycemic target ranges should be established, but many among us believe the glycemic targets endorsed by national guidelines (ref ADA and AACE guidelines)11, 12 are too stringent. Furthermore, we believe that achieving glycemic control is just one small part of the needed improvement efforts. Uncontrolled hyperglycemia is common, potentially dangerous, and largely preventable with safe and proven methodsbut so are the iatrogenic hypoglycemia episodes, substandard education, poor communication, lack of care coordination, and inadequate monitoring that typify care of the hyperglycemic inpatient. We address all of these issues and urge the adoption of this broader perspective.

THE EVIDENCE IS INCOMPLETEBUT ACTION IS REQUIRED

We acknowledge gaps and inconsistencies in the literature surrounding inpatient diabetes management and the controversy around tight glycemic control. In many cases, high level evidence is not available to guide the formulation of protocols, order sets, or other improvement tools. We are all struck by how pervasive the lack of evidence is. What is the best metric for inpatient glycemic control or hypoglycemia? What is the best regimen for a patient on continuous tube feedings? Which insulin infusion protocol is superior in reaching and maintaining a glycemic target range?

Rather than make no recommendations or accept negative inertia on the basis of less than perfect evidence, we make recommendations based on the best evidence available. When we make recommendations based on consensus opinion or the collective experience from dozens of medical centers, rather than randomized trials, we have made every effort to make this clear in the text of the articles. In our view, incomplete evidence is not an adequate excuse to persist in the unacceptable status quo, clinging on to methods (such as sliding scale insulin regimens) that have been shown to be ineffective and potentially dangerous.1315

COLLABORATION PAYS DIVIDENDS

It takes a multidisciplinary approach to make substantial improvement in glycemic control of hospitalized patients. By the same token, it is unlikely that any one group can advance the national agenda for improved care as well as a multidisciplinary coordinated effort. Team members, especially the endocrinologists and hospitalists, collaborated skillfully throughout this effort. The hospitalists learned a tremendous amount from the expertise, insight, and mastery of the literature, offered by the endocrinology members, whereas the endocrinologists appreciated the front line expertise and practical quality improvement approach of the hospitalist members. This collaboration serves as a model for making guidelines and best practices become more of a practical reality for a variety of important clinical problems. Hospitalists can partner with and learn from a variety of other disciplines, while they assist these disciplines on effective improvement and implementation efforts. On a more personal note, this work has fostered mutual respect, friendship, and career long collaborative opportunities. The potential for these same opportunities with nursing, pharmacy, and all medical and surgical fields seems compelling and exciting.

THERE'S MORE!

By the time this is published, these articles will be integrated into the third iteration of the SHM Glycemic Control Resource Room. This online resource has already undergone 2 major revisions since its inception just a few years ago, reflecting SHM's dedication to the continuous improvement of the products and services that it offers. The Glycemic Control Implementation Guide and Resource Room will continue to be a work in progress. We highly encourage and welcome constructive criticism and feedback via E‐mail to [email protected]. The resource room contains a wealth of tools, slide shows, literature reviews, and links, in addition to the core articles published in this Supplement.

NEXT STEPS

More research and demonstration projects are obviously needed in this field. Local collaborative activities have sprung up in several cities and regions, as well as Glycemic Control Champions courses. A longitudinal mentoring program (similar to the SHM Venous Thromboembolism Prevention collaborative) would undoubtedly be beneficial, and may become available within the next year or so. These items and more will be promoted and posted in the resource room whenever possible.

Finally, the next step is up to you and the institutions in which you workyou have to decide, as individuals and institutions, if you believe the status quo is good enough. We believe that if you look, you'll find the care of our inpatients with diabetes and hyperglycemia disturbingly suboptimal, and hope that the work of the SHM Glycemic Control Task Force can help you rapidly improve on this state of affairs.

APPENDIX: GLYCEMIC CONTROL TASK FORCE

The Society of Hospital Medicine thanks all the members of the Glycemic Control Task Force, who encompass a distinguished panel of experts with representation from the AACE, ADA, ACP, and other organizations whose expertise was essential to the construction of the Glycemic Control Resource Room and the Implementation Guide for Glycemic Control and Prevention of Hypoglycemia.

Recently, there has been a heightened interest in improving the quality and safety of the management of diabetes and hyperglycemia in the hospital.1 While observational data strongly suggests an association of hyperglycemia with morbidity and mortality in adults on general medicine and surgery units, clinical research has not yet defined the best practices for managing hyperglycemia in the hospital outside the intensive care unit (ICU). As a result, many physicians do not have a well‐formulated approach to managing hyperglycemia in the noncritically ill hospital patient, and the use of insulin therapy to attain targeted blood glucose (BG) control is often subject to practice variability, leading to suboptimal glycemic outcomes.

Practical guidelines for the management of this common clinical problem have been formulated by experts in the field, based on understanding of the physiology of glucose and insulin dynamics, the characteristics of currently available insulin preparations, and clinical experience. In 2004, in Clement et al.,2 the American Diabetes Association published a technical review promoting the use of physiologic (basal‐nutritional‐correction dose) insulin regimens in the hospital to achieve targeted glycemic outcomes. This approach has been disseminated via review articles,3 and more recently, a randomized, controlled trial demonstrated that hospitalized type 2 diabetes patients experienced better glycemic control when treated with a physiologic insulin regimen than when treated with sliding‐scale insulin alone.4 The Society of Hospital Medicine has assembled a Glycemic Control Task Force, which is charged with providing physicians and hospitals with practical tools to improve the safety and efficacy of diabetes management in the hospital. One product of this work is an educational module that serves as a tutorial on the best practice for the management of diabetes and hyperglycemia in the noncritically ill hospital patient.5 This article is based on that module, and provides a practical summary of the key concepts that will allow clinicians to confidently employ physiologic insulin regimens when caring for their hospital patients.

Case: Ms. X is a 56‐year‐old obese woman with type 2 diabetes mellitus who is admitted for treatment of an infected diabetes‐related foot ulcer. The patient will be allowed to eat dinner in a couple of hours, but the surgeons have requested that she be kept nothing by mouth (NPO) after midnight for surgical debridement in the morning. Her current weight is 100 kg, and her recent glycemic control can be summarized as having BG values that are usually in the mid‐200s (mg/dL) and a recent glycosylated hemoglobin (HbA1C) measurement of 10.9%. Her home medical regimen includes glipizide 10 mg daily, metformin 1000 mg twice daily, and 20 units of neutral protamine hagadorn (NPH) insulin at bedtime. Her blood glucose in the Emergency Department is 289 mg/dL. How should this patient's blood glucose be managed in the hospital?

PHARMACOLOGIC CONTROL OF BG IN THE HOSPITAL: INSULIN IS THE ANTIHYPERGLYCEMIC AGENT OF CHOICE

Although oral antihyperglycemic agents are frequently used in the outpatient setting, there are many potential disadvantages to using these medications in acutely ill hospital patients, as shown in Figure 1.2, 3 Oral antihyperglycemic agents, in general, are difficult to quickly titrate to effect, and have side effects that can limit their use in the hospital. Metformin can lead to lactic acidosis when it is used in clinical situations that predispose to lactate production (eg, renal failure, circulatory failure, hypoxemia). Therefore, metformin should be held in patients who have, or are at risk for, these conditions, each of which may be encountered in the hospital. Also, agents that stimulate the release of insulin, such as sulfonylureas, should be held in patients with variable nutritional intake, to prevent hypoglycemia. In contrast, insulin acts rapidly, responds in a timely fashion to dose titrations, and can be used effectively in virtually all patients and clinical situations to control BG levels. This makes insulin the treatment of choice for hyperglycemia in the hospital. Insulin can be administered via subcutaneous doses or as an intravenous infusion for cases in which rapid titration is the goal. Intravenous insulin infusions are the preferred mode of insulin delivery in the ICU setting, and may be appropriate for some noncritically ill patients in hospitals that have developed systems to safely provide them on general wards. Subcutaneous insulin is most commonly used in the noncritically ill patient population and is the focus of this article.

Figure 1

Although insulin is the drug of choice for managing hyperglycemia in the hospital, there are some situations when it is appropriate to continue oral antihyperglycemic medications in the hospital. These agents may be continued in hospitalized patients who are clinically stable, and who have normal nutritional intake, normal BG levels, and stable renal and cardiac function. They may also be started or resumed in the hospital if they are to be included in the discharge medication regimen once the patient is clinically stable and if it has been assured that contraindications to their use no longer exist.

Ms. X should be treated with a more robust (physiologic) insulin regimen. This statement would be true, even if she were not an inpatient with a foot infection. Her glycemic control is currently poor, as evidenced by her high HbA1C and her elevated admission BG, and is unlikely to be appreciably improved with the addition of any pharmacologic agent other than insulin. The glipizide should be held, as the patient will be NPO after midnight. Most experts would recommend holding the metformin at this time as well, since the patient will be undergoing a surgical procedure in the morning that places her at risk for predisposing factors to lactic acidosis.

INPATIENT GLYCEMIC TARGETS

At present, recommended glycemic targets for noncritically ill hospital patients are based entirely on expert opinion, as there have been no clinical studies directly comparing different glycemic targets in this patient population. However, the American College of Endocrinology, the American Association of Clinical Endocrinologists, and the American Diabetes Association do provide recommendations about glycemic targets for inpatients (Table 1).6, 7 Although controversial, these recommendations make it clear that uncontrolled hyperglycemia is no longer the accepted standard of care for hospitalized patients, and illustrate the consensus of expert opinion on the subject. Of note, many hospitals are adopting glycemic targets that are less stringent than those shown in Table 1, recognizing the challenges of controlling BG levels in hospitalized patients, and the potential risk for hypoglycemia when lower BG targets are used. Each hospital's glycemic control champions must reach consensus on a target BG range for their institution. In practice this range has been 90110 mg/dL for the lower BG limit and 140180 mg/dL for the upper BG limit. It is also important to note that the recommendations from professional organizations emphasize the need to individualize BG targets, based on the clinical circumstances of each patient.

Ms. X is exhibiting glycemic values far outside of the recommended upper limit of 180 mg/dL, and treatment with insulin monotherapy is the most appropriate strategy in this case.

PHYSIOLOGIC (BASAL‐BOLUS, PLUS CORRECTION DOSE) INSULIN

The management of hyperglycemia and diabetes in the inpatient setting is challenging due to the many changes that patients experience in the hospital. Hospitalized patients often experience changes in their nutritional intake and their medication regimen. In addition, hospitalized patients usually experience the stress of acute illness and are treated with medications that might impact glycemic control. Figure 2 lists some of the barriers to achieving glycemic control in hospitalized patients. The inpatient insulin program needs to be flexible enough to allow for maintenance of glycemic control in the face of tumultuous circumstances. This can best be accomplished by the use of a physiologic insulin program. This means using exogenous insulin to mimic normal physiologic insulin activity by providing the correct types and doses of insulin at the correct times.

Figure 2

A physiologic insulin regimen can be conceptualized as having 3 separate components: basal insulin, nutritional (or prandial/meal) insulin, and correction dose (or supplemental) insulin.2 A patient's total daily dose (TDD) of insulin is the sum of all of these, and represents the amount of insulin that a patient requires over the course of 1 day while receiving adequate nutrition. Basal insulin is the insulin normally released continuously by the pancreas, even when fasting. This serves to suppress glucose and ketone production. When nutrition is ingested, there is a surge in the level of glucose in the blood, and this surge is accompanied by rapid secretion of additional insulin to allow for the appropriate utilization of the glucose. The insulin that is secreted in response to nutritional intake is referred to as nutritional insulin. About one‐half of the total daily insulin secreted by a healthy normal human serves a basal function, and about one‐half is secreted in response to nutritional intake.8 Understanding this bit of physiology (the 50/50 rule) is very helpful for creating flexible regimens using exogenous insulin. Although the 50/50 rule is useful in many circumstances, there are some notable exceptions. In some cases, basal insulin might be expected to be less than one‐half of the TDD (eg, enteral feeds, as discussed below). Additional correction dose insulin is given to correct hyperglycemia that occurs despite scheduled doses of basal and nutritional insulin.

It is an important practical consideration to note that when a person with diabetes is acutely ill or stressed, as is commonly the case in the hospital setting, total daily insulin requirements increase. This is due to the action of insulin counterregulatory hormones such as catecholamines, cortisol, growth hormone, and glucagon. The hospitalized patient is therefore likely to require a TDD that is higher than that required when well. This is particularly true for the basal insulin dose. Conversely, insulin requirements will decrease as a patient recovers from acute illness, and it may be necessary to lower insulin doses as BG levels decrease during convalescence.

Exogenous basal insulin is provided as a long‐acting or intermediate‐acting, low‐peaking or nonpeaking insulin (eg, glargine or detemir), that allows for a consistent level of basal insulin (Figure 3). This insulin is provided even when the person is not receiving any nutrition. Although twice daily NPH insulin can be used to provide basal insulin, the peak (as shown in Figure 3) is likely to exceed the level of insulin that is truly required for basal needs, which can result in hypoglycemia. In theory, NPH insulin would be less physiologic than glargine or detemir, although no studies have compared these insulins in the hospital setting. When using NPH insulin as a basal insulin in a patient who is designated NPO, the dose should be reduced by one‐third to one‐half to avoid hypoglycemia that may occur when it peaks.2

Figure 3

Exogenous nutritional insulin must be provided in a way that matches the nutrition that is being provided to the patient. For example, a patient who is receiving nutritional boluses (ie, meals or bolus tube feeds) can be given rapid‐acting insulin (eg, aspart, glulisine, lispro) along with each nutritional bolus to cover the glycemic peak that is caused by the meal. The rapid‐acting analog insulins can also be given at the end of a meal or bolus tube feed for cases in which it is not clear if the nutrition will be well tolerated. A reduction in the insulin dose proportionate to the amount of nutrition actually taken can then be made to decrease the risk of subsequent hypoglycemia. Regular insulin can also be given in anticipation of a meal or tube feed, but its later peak (as shown in Figure 3) requires that it be given 30 minutes before a meal is ingested, the timing of which is a challenge on most nursing units. Patients who are not receiving any nutrition should not receive nutritional insulin. And, patients receiving alternative forms of nutrition will require different nutritional insulin regimens to adequately cover their nutritional glycemic loads, as discussed below.

The separate provision of basal and nutritional insulin results in a highly‐flexible insulin program that can provide basal insulin to patients even when they are not receiving significant nutrition, and can be easily adjusted to provide appropriate nutritional insulin to match actual nutritional delivery.

Correction‐dose insulin is the small amount of insulin that is given to patients, in addition to basal and nutritional insulin, to correct hyperglycemia. Correction‐dose insulin is usually provided as rapid‐acting or regular insulin (usually the same type as the nutritional insulin), and is given in a dose that is specifically designed to reduce the patient's BG back into the target range. It is usually given at the same time as the nutritional insulin in patients who are receiving nutrition (or every 4 to 6 hours in patients who are not). Correction‐dose insulin is often written in a stepped format, to provide the appropriate amount of insulin for a given BG value. It differs from the traditional sliding‐scale in that it is not used alone (but rather as 1 component of a physiologic program), and in that it is customized to match the insulin sensitivity for each patient. Most standardized order sets for subcutaneous insulin provide several different correction‐dose scales to choose from, depending on the patient's weight or total daily insulin requirement.

If correction‐dose insulin is required consistently, or in high doses, it suggests a need to modify the basal and/or nutritional insulin. A proportion of the total number of units of correction‐dose insulin given in the preceding 24 hours can be distributed into basal and nutritional insulin doses for the next day if there is ongoing need for significant correction‐doses of insulin. A well‐designed, physiologic insulin regimen should provide targeted glycemic control, without a need for constantly adding large correctional boluses.

Some insulins do not fit neatly into either basal or nutritional insulin categories. For example, mixed insulins (eg, 70/30, rapid‐analog/NPH mixtures) combine basal and nutritional insulins to form either a double‐peaking insulin or an intermediate‐peaking insulin. The use of this type of insulin makes it impossible to manipulate the basal and nutritional components separately to enable attainment of BG targets. Therefore, the role of this type of insulin is limited in the hospital setting. Mixed insulins may, however, be started once the patient is clinically stable if they will be part of the discharge regimen.

Diabetes and hyperglycemia in the hospitalized patient require active management, and there are no autopilot insulin regimens. The use of sliding scale insulin alone to manage hyperglycemia is a common practice in hospitals.9 However, this is an historic practice that is based on the erroneous idea that BG can be managed with a reactive strategy. When sliding‐scale insulin is used as the sole modality of insulin therapy, insulin is provided only after metabolic control has been lost, and usually does not provide an appropriate dose of insulin, considering basal, nutritional, and correctional needs. The end result is poor glycemic control.9, 10 A recent randomized, controlled trial demonstrated that a physiologic insulin regimen is indeed superior to a standardized insulin sliding‐scale for managing inpatient hyperglycemia.4

Ms. X should be given an insulin regimen that includes basal, nutritional, and correctional components. The provision of separate basal and nutritional insulin will allow the clinicians to provide the patient with basal insulin even when her nutritional insulin is held, and to easily modify her nutritional insulin, depending on her nutritional intake.

PHYSIOLOGIC INSULIN: A PRACTICAL APPROACH

The use of physiologic insulin in the hospital can be facilitated by considering a stepwise approach (Figure 4).5 The first step is to estimate the amount of insulin that the patient will require over the course of a day if taking adequate nutrition (this is the TDD). If the patient has been treated with subcutaneous insulin before being admitted to the hospital, the clinician can use the outpatient TDD to gauge the insulin needs. To do this, the clinician simply adds up the total number of units of insulin that a patient takes at home in a day. Using this method to estimate the patient's TDD can be very helpful, even if the clinician plans to use different types of insulin while the patient is hospitalized. When using this approach, one should consider the patient's prior metabolic control on the existing regimen (ie, if the patient's glycemic control was poor on the preexisting regimen, an increase in the TDD would be necessary). In addition, clinicians should recognize that insulin requirements usually increase when patients are acutely ill, as discussed above. Managing diabetes and hyperglycemia in the hospital is very different than doing so in the outpatient arena, and hospitalists should not feel bound by the outpatient regimen.

Figure 4

In addition, a weight‐based estimation of the TDD can be very helpful in determining a starting dose of insulin in a hospitalized patient (see Figure 5). An estimate of 0.4 units/kg of body weight provides a conservative starting point for the TDD for most patients. Occasionally, a lower starting dose of 0.3 units/kg of body weight might be safer for those patients who are likely to be very sensitive to insulin, or who are otherwise at increased at risk for hypoglycemia (see Figure 5). Patients who are overweight or obese often require considerably higher TDDs in the range of 0.5‐0.6 (or even more) units/kg of body weight. Some may require over 1 unit/kg of body weight for their TDD. Therefore, the doses provided by these calculations represent conservative estimates in most patients. Hospitalists should be able to confidently make these dose estimates and avoid dependence on nonphysiologic regimens such as sliding‐scale insulin alone.

Figure 5

The presence of risk factors for hypoglycemia or hyperglycemia should temper the dose calculations. Clinical conditions associated with hyperglycemia include obesity, certain medications (eg, glucocorticoids, catecholamines, tacrolimus, cyclosporine), and changes in nutritional intake (Figure 2). Clinical conditions associated with hypoglycemia are summarized in Figure 6. It is important to recognize that these calculations are intended to give the clinician a safe and rational starting point for insulin dosing. More important than the calculations is the careful monitoring of BG levels and timely modifications of the insulin regimen that follow.

Figure 6

The second step in developing a physiologic insulin regimen is to determine the patient's nutritional regimen. The third step, then, is to decide how the TDD will be distributed into basal and nutritional insulins, and which insulin will be used for each. As noted above, for most patients, approximately one‐half of the TDD will be provided as basal insulin, and the other one‐half given as nutritional insulin. When patients are receiving nutrition, the insulin must be given in a way that matches the timing of nutrition delivery (eg, with each meal or bolus tube feeding), and provides appropriate insulin coverage for the nutrition that is being provided.

Nutritional insulin will not be given if the patient is not receiving any nutrition, in which case basal insulin and correction‐dose insulin will usually be continued. Table 2 shows the preferred insulin regimens for a variety of different nutritional circumstances, as put forth by the Society of Hospital Medicine (SHM) Glycemic Control Task Force.5

For Ms. X, the first step is to determine a TDD estimate. This patient weighs 100 kg, and is obese. Therefore, a TDD of 0.5 units/kg (50 units) is appropriate. This dose may be an underestimate of her insulin needs, but it is a conservative, reasonable starting point. The patient's basal insulin could be provided by giving one‐half of the TDD as basal insulin, such as glargine, 25 units daily. In this case, the patient will be eating dinner soon, but then will be NPO after midnight for surgery. Appropriate nutritional insulin could be provided by giving one‐third of her total nutritional insulin before this meal as a rapid‐acting insulin analog (25 units nutritional insulin per day divided by 3 meals results in a dose of 8 units per meal). After she eats dinner, additional nutritional insulin will not be given until she resumes her diet postoperatively. While NPO, her basal insulin should be continued, and her blood glucose should be checked every 4‐6 hours. An appropriate correction‐dose insulin scale should be chosen to provide a supplemental insulin dose with each bedside test of the blood glucose level, if and only if, hyperglycemia is present.

Case continued: The patient is given 8 units of lispro insulin before her dinner, and is also given a dose of 25 units of glargine insulin. She is held NPO after midnight and dextrose‐containing fluid is provided intravenously overnight at a maintenance rate. In the morning her blood glucose is 161 mg/dL before surgery. Surgery goes well, and at lunch her blood glucose is 179 mg/dL, and she is given a food tray. However, the patient says that she feels mildly nauseated, and is not sure that she will be able to eat her lunch. How should her nutritional insulin be managed in this situation?

MATCHING NUTRITION AND NUTRITIONAL INSULIN: A DIFFICULT CHALLENGE

It is the provision of the correct type and amount of nutritional insulin at the right time that is most challenging in the hospital. In the hospital, a patient's nutritional intake is often interrupted. Patients might be made NPO as part of the treatment plan, or may not be able to take nutrition by mouth because of specific medical conditions. In some cases, enteral or parenteral feeding is used to replace or enhance oral feeding. Even when alternate routes of nutrition are employed, sudden interruptions in nutrition still remain common (eg, the feeding tube falls out). Ultimately, to provide the best possible care to a diabetes patient, the nutritional insulin that is delivered must match the actual nutritional delivery (Table 2). Ideally, each institution should choose a preferred, standardized approach for each nutritional situation.

Even if institutions standardize their approach to nutritional insulin delivery in general, clinicians must be able to accurately respond to the unplanned variations in nutrition that occur in the hospital. One example of this is the patient who is expected to eat meals, but who becomes suddenly unable to do so, such as in the case above. In cases like this, the best approach is to hold the patient's nutritional insulin and allow the patient to attempt to eat the provided meal. Then, a rapid‐acting insulin analog can be given just after the meal, in proportion to the amount of the meal that was eaten. If the patient really is unable to tolerate any of the meal, then no nutritional insulin is provided. If the patient does tolerate a portion of the meal (eg, 50% of the meal is consumed), then a corresponding amount of insulin is given (eg, 50% of the scheduled nutritional insulin is given). The quick onset of the rapid‐acting insulin analogs allows near‐physiologic effect, even when they are given after the meal.

Ms. X should be allowed to eat as much of the meal as she can tolerate. Afterward, her intake can be assessed, and insulin can be provided in proportion to the amount of the meal that was eaten, as described above.

TYPE 1 DIABETES

Because type 2 diabetes is more prevalent than type 1 diabetes, hospitalists will manage this form of diabetes most often. However, it is crucial that hospitalists are also able to manage type 1 diabetes in the hospital. For the most part, the principles presented in this article apply to all types of diabetes patients. This section outlines some special considerations to remember when caring for type 1 diabetes patients in the hospital that will assure prevention of diabetic ketoacidosis in patients with type 1 diabetes.

Type 1 diabetes patients completely lack endogenous insulin production. Therefore, these patients require exogenous insulin to be provided at all times. Type 1 diabetes patients need to be provided continuous, exogenous basal insulin, even when fasting, to suppress gluconeogenesis and ketone production. Failure to provide basal insulin to a type 1 diabetes patient can lead to the rapid development (in hours) of ketoacidosis. When receiving nutrition, the patient with type 1 diabetes must also be provided with nutritional insulin to control postprandial BGs. Whereas many type 2 diabetes patients may produce sufficient endogenous insulin to meet basal requirements when fasting (ie, they produce enough basal insulin to maintain metabolic stability when they are not taking in nutrition), this is never the case for type 1 diabetes patients.

In addition, type 1 diabetes patients typically exhibit less insulin resistance than type 2 diabetes patients, especially if they are not obese. Therefore, type 1 diabetes patients often have TDDs of insulin that are lower than those of type 2 patients. This is reflected in the recommendations in Figure 5, with the TDD of insulin estimate for a lean type 1 diabetes patient of 0.3 units/kg/day.

CONTINUOUS SUBCUTANEOUS INSULIN INFUSIONS (INSULIN PUMPS) IN THE HOSPITAL

Continuous subcutaneous insulin infusion therapy (CSII), often referred to as insulin pump therapy, involves the use of a pump to provide a continuous flow of subcutaneous basal insulin (usually a rapid‐acting analog) through a needle that is left in place. This basal rate is adjustable, and therefore can be customized to meet variable needs over a 24‐hour period. When the patient takes in nutrition, a bolus of the same insulin is given, via the pump, at a dose that is appropriate to cover the nutritional intake. The advantages of CSII therapy are the capacity for precision and flexibility of the basal insulin delivery (compared to the use of a once‐daily or twice‐daily dose of long‐acting insulin analog), and the lack of a need to inject insulin boluses (which are delivered via the pump). This type of therapy is preferred by some diabetes patients, and although it is not highly prevalent in most areas, it is common enough that hospitalists must have a plan for managing it in their practices.

There are many barriers to the use of CSII in the hospital. Most of these barriers are related to the need for constant management of the pump. Most hospitalists and nurses do not have the expertise to manage this therapy in the hospital. Although the patient (or caregiver) might have the expertise to manage the pump, this is an acceptable option only if the patient is competent to manage the pump. Patient competence to use the pump must be formally assessed and documented, and the patient must agree to perform the many components of care related to managing the pump (eg, documenting the basal rate and boluses given, documenting BGs, providing tubing and other supplies).

Many hospitals currently choose a policy of converting insulin pump therapy to standard subcutaneous insulin treatment for most hospitalized patients. Usually the conversion of CSII to a physiologic subcutaneous insulin regimen (as detailed in this article) is fairly straightforwardthe basal insulin will be given as long‐acting, low‐peaking insulin, and nutritional and correction‐dose insulin can then be added as a rapid‐acting analog, in accord with the patient's needs.

Hospitals that admit a large number of insulin pump patients, or those that choose to use pumps routinely in the hospital, should create a formal policy for pump use.11 It has been suggested that the policy should assure that there is formal assessment of the patient's competence to manage the pump, that there is professional oversight of the pump management (usually via endocrinology and diabetes educator consultation), that contraindications for CSII use are clearly stated, and that there is a formal mechanism for engaging the patient and informing him of his roles and responsibilities (eg, a written agreement). The clinician must write insulin orders in the medical record that specify the basal and bolus insulin doses which are being used. Pump use may be limited to floors where nurses receive at least basic education in the principles of CSII pumps.

CARE TRANSITIONS IN THE HOSPITAL

CONCLUSIONS

Understanding the basic principles of the physiologic (basal, nutritional, and correction‐dose) insulin regimen will allow clinicians to formulate safe and effective insulin regimens in virtually any clinical situation. Simple steps can allow safe estimates of initial doses and titration toward glycemic goals. Additional information and case studies can be found in a Society of Hospital Medicine Task Force Educational Module,5 available online.

Additional resources for improving glycemic control in hospital patients are available online at the Glycemic Control Resource Room (http://www.hospitalmedicine.org/ResourceRoomRedesign/ GlycemicControl.cfm).

Recently, there has been a heightened interest in improving the quality and safety of the management of diabetes and hyperglycemia in the hospital.1 While observational data strongly suggests an association of hyperglycemia with morbidity and mortality in adults on general medicine and surgery units, clinical research has not yet defined the best practices for managing hyperglycemia in the hospital outside the intensive care unit (ICU). As a result, many physicians do not have a well‐formulated approach to managing hyperglycemia in the noncritically ill hospital patient, and the use of insulin therapy to attain targeted blood glucose (BG) control is often subject to practice variability, leading to suboptimal glycemic outcomes.

Practical guidelines for the management of this common clinical problem have been formulated by experts in the field, based on understanding of the physiology of glucose and insulin dynamics, the characteristics of currently available insulin preparations, and clinical experience. In 2004, in Clement et al.,2 the American Diabetes Association published a technical review promoting the use of physiologic (basal‐nutritional‐correction dose) insulin regimens in the hospital to achieve targeted glycemic outcomes. This approach has been disseminated via review articles,3 and more recently, a randomized, controlled trial demonstrated that hospitalized type 2 diabetes patients experienced better glycemic control when treated with a physiologic insulin regimen than when treated with sliding‐scale insulin alone.4 The Society of Hospital Medicine has assembled a Glycemic Control Task Force, which is charged with providing physicians and hospitals with practical tools to improve the safety and efficacy of diabetes management in the hospital. One product of this work is an educational module that serves as a tutorial on the best practice for the management of diabetes and hyperglycemia in the noncritically ill hospital patient.5 This article is based on that module, and provides a practical summary of the key concepts that will allow clinicians to confidently employ physiologic insulin regimens when caring for their hospital patients.

Case: Ms. X is a 56‐year‐old obese woman with type 2 diabetes mellitus who is admitted for treatment of an infected diabetes‐related foot ulcer. The patient will be allowed to eat dinner in a couple of hours, but the surgeons have requested that she be kept nothing by mouth (NPO) after midnight for surgical debridement in the morning. Her current weight is 100 kg, and her recent glycemic control can be summarized as having BG values that are usually in the mid‐200s (mg/dL) and a recent glycosylated hemoglobin (HbA1C) measurement of 10.9%. Her home medical regimen includes glipizide 10 mg daily, metformin 1000 mg twice daily, and 20 units of neutral protamine hagadorn (NPH) insulin at bedtime. Her blood glucose in the Emergency Department is 289 mg/dL. How should this patient's blood glucose be managed in the hospital?

PHARMACOLOGIC CONTROL OF BG IN THE HOSPITAL: INSULIN IS THE ANTIHYPERGLYCEMIC AGENT OF CHOICE

Although oral antihyperglycemic agents are frequently used in the outpatient setting, there are many potential disadvantages to using these medications in acutely ill hospital patients, as shown in Figure 1.2, 3 Oral antihyperglycemic agents, in general, are difficult to quickly titrate to effect, and have side effects that can limit their use in the hospital. Metformin can lead to lactic acidosis when it is used in clinical situations that predispose to lactate production (eg, renal failure, circulatory failure, hypoxemia). Therefore, metformin should be held in patients who have, or are at risk for, these conditions, each of which may be encountered in the hospital. Also, agents that stimulate the release of insulin, such as sulfonylureas, should be held in patients with variable nutritional intake, to prevent hypoglycemia. In contrast, insulin acts rapidly, responds in a timely fashion to dose titrations, and can be used effectively in virtually all patients and clinical situations to control BG levels. This makes insulin the treatment of choice for hyperglycemia in the hospital. Insulin can be administered via subcutaneous doses or as an intravenous infusion for cases in which rapid titration is the goal. Intravenous insulin infusions are the preferred mode of insulin delivery in the ICU setting, and may be appropriate for some noncritically ill patients in hospitals that have developed systems to safely provide them on general wards. Subcutaneous insulin is most commonly used in the noncritically ill patient population and is the focus of this article.

Figure 1

Although insulin is the drug of choice for managing hyperglycemia in the hospital, there are some situations when it is appropriate to continue oral antihyperglycemic medications in the hospital. These agents may be continued in hospitalized patients who are clinically stable, and who have normal nutritional intake, normal BG levels, and stable renal and cardiac function. They may also be started or resumed in the hospital if they are to be included in the discharge medication regimen once the patient is clinically stable and if it has been assured that contraindications to their use no longer exist.

Ms. X should be treated with a more robust (physiologic) insulin regimen. This statement would be true, even if she were not an inpatient with a foot infection. Her glycemic control is currently poor, as evidenced by her high HbA1C and her elevated admission BG, and is unlikely to be appreciably improved with the addition of any pharmacologic agent other than insulin. The glipizide should be held, as the patient will be NPO after midnight. Most experts would recommend holding the metformin at this time as well, since the patient will be undergoing a surgical procedure in the morning that places her at risk for predisposing factors to lactic acidosis.

INPATIENT GLYCEMIC TARGETS

At present, recommended glycemic targets for noncritically ill hospital patients are based entirely on expert opinion, as there have been no clinical studies directly comparing different glycemic targets in this patient population. However, the American College of Endocrinology, the American Association of Clinical Endocrinologists, and the American Diabetes Association do provide recommendations about glycemic targets for inpatients (Table 1).6, 7 Although controversial, these recommendations make it clear that uncontrolled hyperglycemia is no longer the accepted standard of care for hospitalized patients, and illustrate the consensus of expert opinion on the subject. Of note, many hospitals are adopting glycemic targets that are less stringent than those shown in Table 1, recognizing the challenges of controlling BG levels in hospitalized patients, and the potential risk for hypoglycemia when lower BG targets are used. Each hospital's glycemic control champions must reach consensus on a target BG range for their institution. In practice this range has been 90110 mg/dL for the lower BG limit and 140180 mg/dL for the upper BG limit. It is also important to note that the recommendations from professional organizations emphasize the need to individualize BG targets, based on the clinical circumstances of each patient.

Ms. X is exhibiting glycemic values far outside of the recommended upper limit of 180 mg/dL, and treatment with insulin monotherapy is the most appropriate strategy in this case.

PHYSIOLOGIC (BASAL‐BOLUS, PLUS CORRECTION DOSE) INSULIN

The management of hyperglycemia and diabetes in the inpatient setting is challenging due to the many changes that patients experience in the hospital. Hospitalized patients often experience changes in their nutritional intake and their medication regimen. In addition, hospitalized patients usually experience the stress of acute illness and are treated with medications that might impact glycemic control. Figure 2 lists some of the barriers to achieving glycemic control in hospitalized patients. The inpatient insulin program needs to be flexible enough to allow for maintenance of glycemic control in the face of tumultuous circumstances. This can best be accomplished by the use of a physiologic insulin program. This means using exogenous insulin to mimic normal physiologic insulin activity by providing the correct types and doses of insulin at the correct times.

Figure 2

A physiologic insulin regimen can be conceptualized as having 3 separate components: basal insulin, nutritional (or prandial/meal) insulin, and correction dose (or supplemental) insulin.2 A patient's total daily dose (TDD) of insulin is the sum of all of these, and represents the amount of insulin that a patient requires over the course of 1 day while receiving adequate nutrition. Basal insulin is the insulin normally released continuously by the pancreas, even when fasting. This serves to suppress glucose and ketone production. When nutrition is ingested, there is a surge in the level of glucose in the blood, and this surge is accompanied by rapid secretion of additional insulin to allow for the appropriate utilization of the glucose. The insulin that is secreted in response to nutritional intake is referred to as nutritional insulin. About one‐half of the total daily insulin secreted by a healthy normal human serves a basal function, and about one‐half is secreted in response to nutritional intake.8 Understanding this bit of physiology (the 50/50 rule) is very helpful for creating flexible regimens using exogenous insulin. Although the 50/50 rule is useful in many circumstances, there are some notable exceptions. In some cases, basal insulin might be expected to be less than one‐half of the TDD (eg, enteral feeds, as discussed below). Additional correction dose insulin is given to correct hyperglycemia that occurs despite scheduled doses of basal and nutritional insulin.

It is an important practical consideration to note that when a person with diabetes is acutely ill or stressed, as is commonly the case in the hospital setting, total daily insulin requirements increase. This is due to the action of insulin counterregulatory hormones such as catecholamines, cortisol, growth hormone, and glucagon. The hospitalized patient is therefore likely to require a TDD that is higher than that required when well. This is particularly true for the basal insulin dose. Conversely, insulin requirements will decrease as a patient recovers from acute illness, and it may be necessary to lower insulin doses as BG levels decrease during convalescence.

Exogenous basal insulin is provided as a long‐acting or intermediate‐acting, low‐peaking or nonpeaking insulin (eg, glargine or detemir), that allows for a consistent level of basal insulin (Figure 3). This insulin is provided even when the person is not receiving any nutrition. Although twice daily NPH insulin can be used to provide basal insulin, the peak (as shown in Figure 3) is likely to exceed the level of insulin that is truly required for basal needs, which can result in hypoglycemia. In theory, NPH insulin would be less physiologic than glargine or detemir, although no studies have compared these insulins in the hospital setting. When using NPH insulin as a basal insulin in a patient who is designated NPO, the dose should be reduced by one‐third to one‐half to avoid hypoglycemia that may occur when it peaks.2

Figure 3

Exogenous nutritional insulin must be provided in a way that matches the nutrition that is being provided to the patient. For example, a patient who is receiving nutritional boluses (ie, meals or bolus tube feeds) can be given rapid‐acting insulin (eg, aspart, glulisine, lispro) along with each nutritional bolus to cover the glycemic peak that is caused by the meal. The rapid‐acting analog insulins can also be given at the end of a meal or bolus tube feed for cases in which it is not clear if the nutrition will be well tolerated. A reduction in the insulin dose proportionate to the amount of nutrition actually taken can then be made to decrease the risk of subsequent hypoglycemia. Regular insulin can also be given in anticipation of a meal or tube feed, but its later peak (as shown in Figure 3) requires that it be given 30 minutes before a meal is ingested, the timing of which is a challenge on most nursing units. Patients who are not receiving any nutrition should not receive nutritional insulin. And, patients receiving alternative forms of nutrition will require different nutritional insulin regimens to adequately cover their nutritional glycemic loads, as discussed below.

The separate provision of basal and nutritional insulin results in a highly‐flexible insulin program that can provide basal insulin to patients even when they are not receiving significant nutrition, and can be easily adjusted to provide appropriate nutritional insulin to match actual nutritional delivery.

Correction‐dose insulin is the small amount of insulin that is given to patients, in addition to basal and nutritional insulin, to correct hyperglycemia. Correction‐dose insulin is usually provided as rapid‐acting or regular insulin (usually the same type as the nutritional insulin), and is given in a dose that is specifically designed to reduce the patient's BG back into the target range. It is usually given at the same time as the nutritional insulin in patients who are receiving nutrition (or every 4 to 6 hours in patients who are not). Correction‐dose insulin is often written in a stepped format, to provide the appropriate amount of insulin for a given BG value. It differs from the traditional sliding‐scale in that it is not used alone (but rather as 1 component of a physiologic program), and in that it is customized to match the insulin sensitivity for each patient. Most standardized order sets for subcutaneous insulin provide several different correction‐dose scales to choose from, depending on the patient's weight or total daily insulin requirement.

If correction‐dose insulin is required consistently, or in high doses, it suggests a need to modify the basal and/or nutritional insulin. A proportion of the total number of units of correction‐dose insulin given in the preceding 24 hours can be distributed into basal and nutritional insulin doses for the next day if there is ongoing need for significant correction‐doses of insulin. A well‐designed, physiologic insulin regimen should provide targeted glycemic control, without a need for constantly adding large correctional boluses.

Some insulins do not fit neatly into either basal or nutritional insulin categories. For example, mixed insulins (eg, 70/30, rapid‐analog/NPH mixtures) combine basal and nutritional insulins to form either a double‐peaking insulin or an intermediate‐peaking insulin. The use of this type of insulin makes it impossible to manipulate the basal and nutritional components separately to enable attainment of BG targets. Therefore, the role of this type of insulin is limited in the hospital setting. Mixed insulins may, however, be started once the patient is clinically stable if they will be part of the discharge regimen.

Diabetes and hyperglycemia in the hospitalized patient require active management, and there are no autopilot insulin regimens. The use of sliding scale insulin alone to manage hyperglycemia is a common practice in hospitals.9 However, this is an historic practice that is based on the erroneous idea that BG can be managed with a reactive strategy. When sliding‐scale insulin is used as the sole modality of insulin therapy, insulin is provided only after metabolic control has been lost, and usually does not provide an appropriate dose of insulin, considering basal, nutritional, and correctional needs. The end result is poor glycemic control.9, 10 A recent randomized, controlled trial demonstrated that a physiologic insulin regimen is indeed superior to a standardized insulin sliding‐scale for managing inpatient hyperglycemia.4

Ms. X should be given an insulin regimen that includes basal, nutritional, and correctional components. The provision of separate basal and nutritional insulin will allow the clinicians to provide the patient with basal insulin even when her nutritional insulin is held, and to easily modify her nutritional insulin, depending on her nutritional intake.

PHYSIOLOGIC INSULIN: A PRACTICAL APPROACH

The use of physiologic insulin in the hospital can be facilitated by considering a stepwise approach (Figure 4).5 The first step is to estimate the amount of insulin that the patient will require over the course of a day if taking adequate nutrition (this is the TDD). If the patient has been treated with subcutaneous insulin before being admitted to the hospital, the clinician can use the outpatient TDD to gauge the insulin needs. To do this, the clinician simply adds up the total number of units of insulin that a patient takes at home in a day. Using this method to estimate the patient's TDD can be very helpful, even if the clinician plans to use different types of insulin while the patient is hospitalized. When using this approach, one should consider the patient's prior metabolic control on the existing regimen (ie, if the patient's glycemic control was poor on the preexisting regimen, an increase in the TDD would be necessary). In addition, clinicians should recognize that insulin requirements usually increase when patients are acutely ill, as discussed above. Managing diabetes and hyperglycemia in the hospital is very different than doing so in the outpatient arena, and hospitalists should not feel bound by the outpatient regimen.

Figure 4

In addition, a weight‐based estimation of the TDD can be very helpful in determining a starting dose of insulin in a hospitalized patient (see Figure 5). An estimate of 0.4 units/kg of body weight provides a conservative starting point for the TDD for most patients. Occasionally, a lower starting dose of 0.3 units/kg of body weight might be safer for those patients who are likely to be very sensitive to insulin, or who are otherwise at increased at risk for hypoglycemia (see Figure 5). Patients who are overweight or obese often require considerably higher TDDs in the range of 0.5‐0.6 (or even more) units/kg of body weight. Some may require over 1 unit/kg of body weight for their TDD. Therefore, the doses provided by these calculations represent conservative estimates in most patients. Hospitalists should be able to confidently make these dose estimates and avoid dependence on nonphysiologic regimens such as sliding‐scale insulin alone.

Figure 5

The presence of risk factors for hypoglycemia or hyperglycemia should temper the dose calculations. Clinical conditions associated with hyperglycemia include obesity, certain medications (eg, glucocorticoids, catecholamines, tacrolimus, cyclosporine), and changes in nutritional intake (Figure 2). Clinical conditions associated with hypoglycemia are summarized in Figure 6. It is important to recognize that these calculations are intended to give the clinician a safe and rational starting point for insulin dosing. More important than the calculations is the careful monitoring of BG levels and timely modifications of the insulin regimen that follow.

Figure 6

The second step in developing a physiologic insulin regimen is to determine the patient's nutritional regimen. The third step, then, is to decide how the TDD will be distributed into basal and nutritional insulins, and which insulin will be used for each. As noted above, for most patients, approximately one‐half of the TDD will be provided as basal insulin, and the other one‐half given as nutritional insulin. When patients are receiving nutrition, the insulin must be given in a way that matches the timing of nutrition delivery (eg, with each meal or bolus tube feeding), and provides appropriate insulin coverage for the nutrition that is being provided.

Nutritional insulin will not be given if the patient is not receiving any nutrition, in which case basal insulin and correction‐dose insulin will usually be continued. Table 2 shows the preferred insulin regimens for a variety of different nutritional circumstances, as put forth by the Society of Hospital Medicine (SHM) Glycemic Control Task Force.5

For Ms. X, the first step is to determine a TDD estimate. This patient weighs 100 kg, and is obese. Therefore, a TDD of 0.5 units/kg (50 units) is appropriate. This dose may be an underestimate of her insulin needs, but it is a conservative, reasonable starting point. The patient's basal insulin could be provided by giving one‐half of the TDD as basal insulin, such as glargine, 25 units daily. In this case, the patient will be eating dinner soon, but then will be NPO after midnight for surgery. Appropriate nutritional insulin could be provided by giving one‐third of her total nutritional insulin before this meal as a rapid‐acting insulin analog (25 units nutritional insulin per day divided by 3 meals results in a dose of 8 units per meal). After she eats dinner, additional nutritional insulin will not be given until she resumes her diet postoperatively. While NPO, her basal insulin should be continued, and her blood glucose should be checked every 4‐6 hours. An appropriate correction‐dose insulin scale should be chosen to provide a supplemental insulin dose with each bedside test of the blood glucose level, if and only if, hyperglycemia is present.

Case continued: The patient is given 8 units of lispro insulin before her dinner, and is also given a dose of 25 units of glargine insulin. She is held NPO after midnight and dextrose‐containing fluid is provided intravenously overnight at a maintenance rate. In the morning her blood glucose is 161 mg/dL before surgery. Surgery goes well, and at lunch her blood glucose is 179 mg/dL, and she is given a food tray. However, the patient says that she feels mildly nauseated, and is not sure that she will be able to eat her lunch. How should her nutritional insulin be managed in this situation?

MATCHING NUTRITION AND NUTRITIONAL INSULIN: A DIFFICULT CHALLENGE

It is the provision of the correct type and amount of nutritional insulin at the right time that is most challenging in the hospital. In the hospital, a patient's nutritional intake is often interrupted. Patients might be made NPO as part of the treatment plan, or may not be able to take nutrition by mouth because of specific medical conditions. In some cases, enteral or parenteral feeding is used to replace or enhance oral feeding. Even when alternate routes of nutrition are employed, sudden interruptions in nutrition still remain common (eg, the feeding tube falls out). Ultimately, to provide the best possible care to a diabetes patient, the nutritional insulin that is delivered must match the actual nutritional delivery (Table 2). Ideally, each institution should choose a preferred, standardized approach for each nutritional situation.

Even if institutions standardize their approach to nutritional insulin delivery in general, clinicians must be able to accurately respond to the unplanned variations in nutrition that occur in the hospital. One example of this is the patient who is expected to eat meals, but who becomes suddenly unable to do so, such as in the case above. In cases like this, the best approach is to hold the patient's nutritional insulin and allow the patient to attempt to eat the provided meal. Then, a rapid‐acting insulin analog can be given just after the meal, in proportion to the amount of the meal that was eaten. If the patient really is unable to tolerate any of the meal, then no nutritional insulin is provided. If the patient does tolerate a portion of the meal (eg, 50% of the meal is consumed), then a corresponding amount of insulin is given (eg, 50% of the scheduled nutritional insulin is given). The quick onset of the rapid‐acting insulin analogs allows near‐physiologic effect, even when they are given after the meal.

Ms. X should be allowed to eat as much of the meal as she can tolerate. Afterward, her intake can be assessed, and insulin can be provided in proportion to the amount of the meal that was eaten, as described above.

TYPE 1 DIABETES

Because type 2 diabetes is more prevalent than type 1 diabetes, hospitalists will manage this form of diabetes most often. However, it is crucial that hospitalists are also able to manage type 1 diabetes in the hospital. For the most part, the principles presented in this article apply to all types of diabetes patients. This section outlines some special considerations to remember when caring for type 1 diabetes patients in the hospital that will assure prevention of diabetic ketoacidosis in patients with type 1 diabetes.

Type 1 diabetes patients completely lack endogenous insulin production. Therefore, these patients require exogenous insulin to be provided at all times. Type 1 diabetes patients need to be provided continuous, exogenous basal insulin, even when fasting, to suppress gluconeogenesis and ketone production. Failure to provide basal insulin to a type 1 diabetes patient can lead to the rapid development (in hours) of ketoacidosis. When receiving nutrition, the patient with type 1 diabetes must also be provided with nutritional insulin to control postprandial BGs. Whereas many type 2 diabetes patients may produce sufficient endogenous insulin to meet basal requirements when fasting (ie, they produce enough basal insulin to maintain metabolic stability when they are not taking in nutrition), this is never the case for type 1 diabetes patients.

In addition, type 1 diabetes patients typically exhibit less insulin resistance than type 2 diabetes patients, especially if they are not obese. Therefore, type 1 diabetes patients often have TDDs of insulin that are lower than those of type 2 patients. This is reflected in the recommendations in Figure 5, with the TDD of insulin estimate for a lean type 1 diabetes patient of 0.3 units/kg/day.

CONTINUOUS SUBCUTANEOUS INSULIN INFUSIONS (INSULIN PUMPS) IN THE HOSPITAL

Continuous subcutaneous insulin infusion therapy (CSII), often referred to as insulin pump therapy, involves the use of a pump to provide a continuous flow of subcutaneous basal insulin (usually a rapid‐acting analog) through a needle that is left in place. This basal rate is adjustable, and therefore can be customized to meet variable needs over a 24‐hour period. When the patient takes in nutrition, a bolus of the same insulin is given, via the pump, at a dose that is appropriate to cover the nutritional intake. The advantages of CSII therapy are the capacity for precision and flexibility of the basal insulin delivery (compared to the use of a once‐daily or twice‐daily dose of long‐acting insulin analog), and the lack of a need to inject insulin boluses (which are delivered via the pump). This type of therapy is preferred by some diabetes patients, and although it is not highly prevalent in most areas, it is common enough that hospitalists must have a plan for managing it in their practices.

There are many barriers to the use of CSII in the hospital. Most of these barriers are related to the need for constant management of the pump. Most hospitalists and nurses do not have the expertise to manage this therapy in the hospital. Although the patient (or caregiver) might have the expertise to manage the pump, this is an acceptable option only if the patient is competent to manage the pump. Patient competence to use the pump must be formally assessed and documented, and the patient must agree to perform the many components of care related to managing the pump (eg, documenting the basal rate and boluses given, documenting BGs, providing tubing and other supplies).

Many hospitals currently choose a policy of converting insulin pump therapy to standard subcutaneous insulin treatment for most hospitalized patients. Usually the conversion of CSII to a physiologic subcutaneous insulin regimen (as detailed in this article) is fairly straightforwardthe basal insulin will be given as long‐acting, low‐peaking insulin, and nutritional and correction‐dose insulin can then be added as a rapid‐acting analog, in accord with the patient's needs.

Hospitals that admit a large number of insulin pump patients, or those that choose to use pumps routinely in the hospital, should create a formal policy for pump use.11 It has been suggested that the policy should assure that there is formal assessment of the patient's competence to manage the pump, that there is professional oversight of the pump management (usually via endocrinology and diabetes educator consultation), that contraindications for CSII use are clearly stated, and that there is a formal mechanism for engaging the patient and informing him of his roles and responsibilities (eg, a written agreement). The clinician must write insulin orders in the medical record that specify the basal and bolus insulin doses which are being used. Pump use may be limited to floors where nurses receive at least basic education in the principles of CSII pumps.

CARE TRANSITIONS IN THE HOSPITAL

CONCLUSIONS

Understanding the basic principles of the physiologic (basal, nutritional, and correction‐dose) insulin regimen will allow clinicians to formulate safe and effective insulin regimens in virtually any clinical situation. Simple steps can allow safe estimates of initial doses and titration toward glycemic goals. Additional information and case studies can be found in a Society of Hospital Medicine Task Force Educational Module,5 available online.

Additional resources for improving glycemic control in hospital patients are available online at the Glycemic Control Resource Room (http://www.hospitalmedicine.org/ResourceRoomRedesign/ GlycemicControl.cfm).

Recently, there has been a heightened interest in improving the quality and safety of the management of diabetes and hyperglycemia in the hospital.1 While observational data strongly suggests an association of hyperglycemia with morbidity and mortality in adults on general medicine and surgery units, clinical research has not yet defined the best practices for managing hyperglycemia in the hospital outside the intensive care unit (ICU). As a result, many physicians do not have a well‐formulated approach to managing hyperglycemia in the noncritically ill hospital patient, and the use of insulin therapy to attain targeted blood glucose (BG) control is often subject to practice variability, leading to suboptimal glycemic outcomes.

Practical guidelines for the management of this common clinical problem have been formulated by experts in the field, based on understanding of the physiology of glucose and insulin dynamics, the characteristics of currently available insulin preparations, and clinical experience. In 2004, in Clement et al.,2 the American Diabetes Association published a technical review promoting the use of physiologic (basal‐nutritional‐correction dose) insulin regimens in the hospital to achieve targeted glycemic outcomes. This approach has been disseminated via review articles,3 and more recently, a randomized, controlled trial demonstrated that hospitalized type 2 diabetes patients experienced better glycemic control when treated with a physiologic insulin regimen than when treated with sliding‐scale insulin alone.4 The Society of Hospital Medicine has assembled a Glycemic Control Task Force, which is charged with providing physicians and hospitals with practical tools to improve the safety and efficacy of diabetes management in the hospital. One product of this work is an educational module that serves as a tutorial on the best practice for the management of diabetes and hyperglycemia in the noncritically ill hospital patient.5 This article is based on that module, and provides a practical summary of the key concepts that will allow clinicians to confidently employ physiologic insulin regimens when caring for their hospital patients.

Case: Ms. X is a 56‐year‐old obese woman with type 2 diabetes mellitus who is admitted for treatment of an infected diabetes‐related foot ulcer. The patient will be allowed to eat dinner in a couple of hours, but the surgeons have requested that she be kept nothing by mouth (NPO) after midnight for surgical debridement in the morning. Her current weight is 100 kg, and her recent glycemic control can be summarized as having BG values that are usually in the mid‐200s (mg/dL) and a recent glycosylated hemoglobin (HbA1C) measurement of 10.9%. Her home medical regimen includes glipizide 10 mg daily, metformin 1000 mg twice daily, and 20 units of neutral protamine hagadorn (NPH) insulin at bedtime. Her blood glucose in the Emergency Department is 289 mg/dL. How should this patient's blood glucose be managed in the hospital?

PHARMACOLOGIC CONTROL OF BG IN THE HOSPITAL: INSULIN IS THE ANTIHYPERGLYCEMIC AGENT OF CHOICE

Although oral antihyperglycemic agents are frequently used in the outpatient setting, there are many potential disadvantages to using these medications in acutely ill hospital patients, as shown in Figure 1.2, 3 Oral antihyperglycemic agents, in general, are difficult to quickly titrate to effect, and have side effects that can limit their use in the hospital. Metformin can lead to lactic acidosis when it is used in clinical situations that predispose to lactate production (eg, renal failure, circulatory failure, hypoxemia). Therefore, metformin should be held in patients who have, or are at risk for, these conditions, each of which may be encountered in the hospital. Also, agents that stimulate the release of insulin, such as sulfonylureas, should be held in patients with variable nutritional intake, to prevent hypoglycemia. In contrast, insulin acts rapidly, responds in a timely fashion to dose titrations, and can be used effectively in virtually all patients and clinical situations to control BG levels. This makes insulin the treatment of choice for hyperglycemia in the hospital. Insulin can be administered via subcutaneous doses or as an intravenous infusion for cases in which rapid titration is the goal. Intravenous insulin infusions are the preferred mode of insulin delivery in the ICU setting, and may be appropriate for some noncritically ill patients in hospitals that have developed systems to safely provide them on general wards. Subcutaneous insulin is most commonly used in the noncritically ill patient population and is the focus of this article.

Figure 1

Although insulin is the drug of choice for managing hyperglycemia in the hospital, there are some situations when it is appropriate to continue oral antihyperglycemic medications in the hospital. These agents may be continued in hospitalized patients who are clinically stable, and who have normal nutritional intake, normal BG levels, and stable renal and cardiac function. They may also be started or resumed in the hospital if they are to be included in the discharge medication regimen once the patient is clinically stable and if it has been assured that contraindications to their use no longer exist.

Ms. X should be treated with a more robust (physiologic) insulin regimen. This statement would be true, even if she were not an inpatient with a foot infection. Her glycemic control is currently poor, as evidenced by her high HbA1C and her elevated admission BG, and is unlikely to be appreciably improved with the addition of any pharmacologic agent other than insulin. The glipizide should be held, as the patient will be NPO after midnight. Most experts would recommend holding the metformin at this time as well, since the patient will be undergoing a surgical procedure in the morning that places her at risk for predisposing factors to lactic acidosis.

INPATIENT GLYCEMIC TARGETS

At present, recommended glycemic targets for noncritically ill hospital patients are based entirely on expert opinion, as there have been no clinical studies directly comparing different glycemic targets in this patient population. However, the American College of Endocrinology, the American Association of Clinical Endocrinologists, and the American Diabetes Association do provide recommendations about glycemic targets for inpatients (Table 1).6, 7 Although controversial, these recommendations make it clear that uncontrolled hyperglycemia is no longer the accepted standard of care for hospitalized patients, and illustrate the consensus of expert opinion on the subject. Of note, many hospitals are adopting glycemic targets that are less stringent than those shown in Table 1, recognizing the challenges of controlling BG levels in hospitalized patients, and the potential risk for hypoglycemia when lower BG targets are used. Each hospital's glycemic control champions must reach consensus on a target BG range for their institution. In practice this range has been 90110 mg/dL for the lower BG limit and 140180 mg/dL for the upper BG limit. It is also important to note that the recommendations from professional organizations emphasize the need to individualize BG targets, based on the clinical circumstances of each patient.

Ms. X is exhibiting glycemic values far outside of the recommended upper limit of 180 mg/dL, and treatment with insulin monotherapy is the most appropriate strategy in this case.

PHYSIOLOGIC (BASAL‐BOLUS, PLUS CORRECTION DOSE) INSULIN

The management of hyperglycemia and diabetes in the inpatient setting is challenging due to the many changes that patients experience in the hospital. Hospitalized patients often experience changes in their nutritional intake and their medication regimen. In addition, hospitalized patients usually experience the stress of acute illness and are treated with medications that might impact glycemic control. Figure 2 lists some of the barriers to achieving glycemic control in hospitalized patients. The inpatient insulin program needs to be flexible enough to allow for maintenance of glycemic control in the face of tumultuous circumstances. This can best be accomplished by the use of a physiologic insulin program. This means using exogenous insulin to mimic normal physiologic insulin activity by providing the correct types and doses of insulin at the correct times.

Figure 2

A physiologic insulin regimen can be conceptualized as having 3 separate components: basal insulin, nutritional (or prandial/meal) insulin, and correction dose (or supplemental) insulin.2 A patient's total daily dose (TDD) of insulin is the sum of all of these, and represents the amount of insulin that a patient requires over the course of 1 day while receiving adequate nutrition. Basal insulin is the insulin normally released continuously by the pancreas, even when fasting. This serves to suppress glucose and ketone production. When nutrition is ingested, there is a surge in the level of glucose in the blood, and this surge is accompanied by rapid secretion of additional insulin to allow for the appropriate utilization of the glucose. The insulin that is secreted in response to nutritional intake is referred to as nutritional insulin. About one‐half of the total daily insulin secreted by a healthy normal human serves a basal function, and about one‐half is secreted in response to nutritional intake.8 Understanding this bit of physiology (the 50/50 rule) is very helpful for creating flexible regimens using exogenous insulin. Although the 50/50 rule is useful in many circumstances, there are some notable exceptions. In some cases, basal insulin might be expected to be less than one‐half of the TDD (eg, enteral feeds, as discussed below). Additional correction dose insulin is given to correct hyperglycemia that occurs despite scheduled doses of basal and nutritional insulin.

It is an important practical consideration to note that when a person with diabetes is acutely ill or stressed, as is commonly the case in the hospital setting, total daily insulin requirements increase. This is due to the action of insulin counterregulatory hormones such as catecholamines, cortisol, growth hormone, and glucagon. The hospitalized patient is therefore likely to require a TDD that is higher than that required when well. This is particularly true for the basal insulin dose. Conversely, insulin requirements will decrease as a patient recovers from acute illness, and it may be necessary to lower insulin doses as BG levels decrease during convalescence.

Exogenous basal insulin is provided as a long‐acting or intermediate‐acting, low‐peaking or nonpeaking insulin (eg, glargine or detemir), that allows for a consistent level of basal insulin (Figure 3). This insulin is provided even when the person is not receiving any nutrition. Although twice daily NPH insulin can be used to provide basal insulin, the peak (as shown in Figure 3) is likely to exceed the level of insulin that is truly required for basal needs, which can result in hypoglycemia. In theory, NPH insulin would be less physiologic than glargine or detemir, although no studies have compared these insulins in the hospital setting. When using NPH insulin as a basal insulin in a patient who is designated NPO, the dose should be reduced by one‐third to one‐half to avoid hypoglycemia that may occur when it peaks.2

Figure 3

Exogenous nutritional insulin must be provided in a way that matches the nutrition that is being provided to the patient. For example, a patient who is receiving nutritional boluses (ie, meals or bolus tube feeds) can be given rapid‐acting insulin (eg, aspart, glulisine, lispro) along with each nutritional bolus to cover the glycemic peak that is caused by the meal. The rapid‐acting analog insulins can also be given at the end of a meal or bolus tube feed for cases in which it is not clear if the nutrition will be well tolerated. A reduction in the insulin dose proportionate to the amount of nutrition actually taken can then be made to decrease the risk of subsequent hypoglycemia. Regular insulin can also be given in anticipation of a meal or tube feed, but its later peak (as shown in Figure 3) requires that it be given 30 minutes before a meal is ingested, the timing of which is a challenge on most nursing units. Patients who are not receiving any nutrition should not receive nutritional insulin. And, patients receiving alternative forms of nutrition will require different nutritional insulin regimens to adequately cover their nutritional glycemic loads, as discussed below.

The separate provision of basal and nutritional insulin results in a highly‐flexible insulin program that can provide basal insulin to patients even when they are not receiving significant nutrition, and can be easily adjusted to provide appropriate nutritional insulin to match actual nutritional delivery.

Correction‐dose insulin is the small amount of insulin that is given to patients, in addition to basal and nutritional insulin, to correct hyperglycemia. Correction‐dose insulin is usually provided as rapid‐acting or regular insulin (usually the same type as the nutritional insulin), and is given in a dose that is specifically designed to reduce the patient's BG back into the target range. It is usually given at the same time as the nutritional insulin in patients who are receiving nutrition (or every 4 to 6 hours in patients who are not). Correction‐dose insulin is often written in a stepped format, to provide the appropriate amount of insulin for a given BG value. It differs from the traditional sliding‐scale in that it is not used alone (but rather as 1 component of a physiologic program), and in that it is customized to match the insulin sensitivity for each patient. Most standardized order sets for subcutaneous insulin provide several different correction‐dose scales to choose from, depending on the patient's weight or total daily insulin requirement.

If correction‐dose insulin is required consistently, or in high doses, it suggests a need to modify the basal and/or nutritional insulin. A proportion of the total number of units of correction‐dose insulin given in the preceding 24 hours can be distributed into basal and nutritional insulin doses for the next day if there is ongoing need for significant correction‐doses of insulin. A well‐designed, physiologic insulin regimen should provide targeted glycemic control, without a need for constantly adding large correctional boluses.

Some insulins do not fit neatly into either basal or nutritional insulin categories. For example, mixed insulins (eg, 70/30, rapid‐analog/NPH mixtures) combine basal and nutritional insulins to form either a double‐peaking insulin or an intermediate‐peaking insulin. The use of this type of insulin makes it impossible to manipulate the basal and nutritional components separately to enable attainment of BG targets. Therefore, the role of this type of insulin is limited in the hospital setting. Mixed insulins may, however, be started once the patient is clinically stable if they will be part of the discharge regimen.

Diabetes and hyperglycemia in the hospitalized patient require active management, and there are no autopilot insulin regimens. The use of sliding scale insulin alone to manage hyperglycemia is a common practice in hospitals.9 However, this is an historic practice that is based on the erroneous idea that BG can be managed with a reactive strategy. When sliding‐scale insulin is used as the sole modality of insulin therapy, insulin is provided only after metabolic control has been lost, and usually does not provide an appropriate dose of insulin, considering basal, nutritional, and correctional needs. The end result is poor glycemic control.9, 10 A recent randomized, controlled trial demonstrated that a physiologic insulin regimen is indeed superior to a standardized insulin sliding‐scale for managing inpatient hyperglycemia.4

Ms. X should be given an insulin regimen that includes basal, nutritional, and correctional components. The provision of separate basal and nutritional insulin will allow the clinicians to provide the patient with basal insulin even when her nutritional insulin is held, and to easily modify her nutritional insulin, depending on her nutritional intake.

PHYSIOLOGIC INSULIN: A PRACTICAL APPROACH

The use of physiologic insulin in the hospital can be facilitated by considering a stepwise approach (Figure 4).5 The first step is to estimate the amount of insulin that the patient will require over the course of a day if taking adequate nutrition (this is the TDD). If the patient has been treated with subcutaneous insulin before being admitted to the hospital, the clinician can use the outpatient TDD to gauge the insulin needs. To do this, the clinician simply adds up the total number of units of insulin that a patient takes at home in a day. Using this method to estimate the patient's TDD can be very helpful, even if the clinician plans to use different types of insulin while the patient is hospitalized. When using this approach, one should consider the patient's prior metabolic control on the existing regimen (ie, if the patient's glycemic control was poor on the preexisting regimen, an increase in the TDD would be necessary). In addition, clinicians should recognize that insulin requirements usually increase when patients are acutely ill, as discussed above. Managing diabetes and hyperglycemia in the hospital is very different than doing so in the outpatient arena, and hospitalists should not feel bound by the outpatient regimen.

Figure 4

In addition, a weight‐based estimation of the TDD can be very helpful in determining a starting dose of insulin in a hospitalized patient (see Figure 5). An estimate of 0.4 units/kg of body weight provides a conservative starting point for the TDD for most patients. Occasionally, a lower starting dose of 0.3 units/kg of body weight might be safer for those patients who are likely to be very sensitive to insulin, or who are otherwise at increased at risk for hypoglycemia (see Figure 5). Patients who are overweight or obese often require considerably higher TDDs in the range of 0.5‐0.6 (or even more) units/kg of body weight. Some may require over 1 unit/kg of body weight for their TDD. Therefore, the doses provided by these calculations represent conservative estimates in most patients. Hospitalists should be able to confidently make these dose estimates and avoid dependence on nonphysiologic regimens such as sliding‐scale insulin alone.

Figure 5

The presence of risk factors for hypoglycemia or hyperglycemia should temper the dose calculations. Clinical conditions associated with hyperglycemia include obesity, certain medications (eg, glucocorticoids, catecholamines, tacrolimus, cyclosporine), and changes in nutritional intake (Figure 2). Clinical conditions associated with hypoglycemia are summarized in Figure 6. It is important to recognize that these calculations are intended to give the clinician a safe and rational starting point for insulin dosing. More important than the calculations is the careful monitoring of BG levels and timely modifications of the insulin regimen that follow.

Figure 6

The second step in developing a physiologic insulin regimen is to determine the patient's nutritional regimen. The third step, then, is to decide how the TDD will be distributed into basal and nutritional insulins, and which insulin will be used for each. As noted above, for most patients, approximately one‐half of the TDD will be provided as basal insulin, and the other one‐half given as nutritional insulin. When patients are receiving nutrition, the insulin must be given in a way that matches the timing of nutrition delivery (eg, with each meal or bolus tube feeding), and provides appropriate insulin coverage for the nutrition that is being provided.

Nutritional insulin will not be given if the patient is not receiving any nutrition, in which case basal insulin and correction‐dose insulin will usually be continued. Table 2 shows the preferred insulin regimens for a variety of different nutritional circumstances, as put forth by the Society of Hospital Medicine (SHM) Glycemic Control Task Force.5

For Ms. X, the first step is to determine a TDD estimate. This patient weighs 100 kg, and is obese. Therefore, a TDD of 0.5 units/kg (50 units) is appropriate. This dose may be an underestimate of her insulin needs, but it is a conservative, reasonable starting point. The patient's basal insulin could be provided by giving one‐half of the TDD as basal insulin, such as glargine, 25 units daily. In this case, the patient will be eating dinner soon, but then will be NPO after midnight for surgery. Appropriate nutritional insulin could be provided by giving one‐third of her total nutritional insulin before this meal as a rapid‐acting insulin analog (25 units nutritional insulin per day divided by 3 meals results in a dose of 8 units per meal). After she eats dinner, additional nutritional insulin will not be given until she resumes her diet postoperatively. While NPO, her basal insulin should be continued, and her blood glucose should be checked every 4‐6 hours. An appropriate correction‐dose insulin scale should be chosen to provide a supplemental insulin dose with each bedside test of the blood glucose level, if and only if, hyperglycemia is present.

Case continued: The patient is given 8 units of lispro insulin before her dinner, and is also given a dose of 25 units of glargine insulin. She is held NPO after midnight and dextrose‐containing fluid is provided intravenously overnight at a maintenance rate. In the morning her blood glucose is 161 mg/dL before surgery. Surgery goes well, and at lunch her blood glucose is 179 mg/dL, and she is given a food tray. However, the patient says that she feels mildly nauseated, and is not sure that she will be able to eat her lunch. How should her nutritional insulin be managed in this situation?

MATCHING NUTRITION AND NUTRITIONAL INSULIN: A DIFFICULT CHALLENGE

It is the provision of the correct type and amount of nutritional insulin at the right time that is most challenging in the hospital. In the hospital, a patient's nutritional intake is often interrupted. Patients might be made NPO as part of the treatment plan, or may not be able to take nutrition by mouth because of specific medical conditions. In some cases, enteral or parenteral feeding is used to replace or enhance oral feeding. Even when alternate routes of nutrition are employed, sudden interruptions in nutrition still remain common (eg, the feeding tube falls out). Ultimately, to provide the best possible care to a diabetes patient, the nutritional insulin that is delivered must match the actual nutritional delivery (Table 2). Ideally, each institution should choose a preferred, standardized approach for each nutritional situation.

Even if institutions standardize their approach to nutritional insulin delivery in general, clinicians must be able to accurately respond to the unplanned variations in nutrition that occur in the hospital. One example of this is the patient who is expected to eat meals, but who becomes suddenly unable to do so, such as in the case above. In cases like this, the best approach is to hold the patient's nutritional insulin and allow the patient to attempt to eat the provided meal. Then, a rapid‐acting insulin analog can be given just after the meal, in proportion to the amount of the meal that was eaten. If the patient really is unable to tolerate any of the meal, then no nutritional insulin is provided. If the patient does tolerate a portion of the meal (eg, 50% of the meal is consumed), then a corresponding amount of insulin is given (eg, 50% of the scheduled nutritional insulin is given). The quick onset of the rapid‐acting insulin analogs allows near‐physiologic effect, even when they are given after the meal.

Ms. X should be allowed to eat as much of the meal as she can tolerate. Afterward, her intake can be assessed, and insulin can be provided in proportion to the amount of the meal that was eaten, as described above.

TYPE 1 DIABETES

Because type 2 diabetes is more prevalent than type 1 diabetes, hospitalists will manage this form of diabetes most often. However, it is crucial that hospitalists are also able to manage type 1 diabetes in the hospital. For the most part, the principles presented in this article apply to all types of diabetes patients. This section outlines some special considerations to remember when caring for type 1 diabetes patients in the hospital that will assure prevention of diabetic ketoacidosis in patients with type 1 diabetes.

Type 1 diabetes patients completely lack endogenous insulin production. Therefore, these patients require exogenous insulin to be provided at all times. Type 1 diabetes patients need to be provided continuous, exogenous basal insulin, even when fasting, to suppress gluconeogenesis and ketone production. Failure to provide basal insulin to a type 1 diabetes patient can lead to the rapid development (in hours) of ketoacidosis. When receiving nutrition, the patient with type 1 diabetes must also be provided with nutritional insulin to control postprandial BGs. Whereas many type 2 diabetes patients may produce sufficient endogenous insulin to meet basal requirements when fasting (ie, they produce enough basal insulin to maintain metabolic stability when they are not taking in nutrition), this is never the case for type 1 diabetes patients.

In addition, type 1 diabetes patients typically exhibit less insulin resistance than type 2 diabetes patients, especially if they are not obese. Therefore, type 1 diabetes patients often have TDDs of insulin that are lower than those of type 2 patients. This is reflected in the recommendations in Figure 5, with the TDD of insulin estimate for a lean type 1 diabetes patient of 0.3 units/kg/day.

CONTINUOUS SUBCUTANEOUS INSULIN INFUSIONS (INSULIN PUMPS) IN THE HOSPITAL

Continuous subcutaneous insulin infusion therapy (CSII), often referred to as insulin pump therapy, involves the use of a pump to provide a continuous flow of subcutaneous basal insulin (usually a rapid‐acting analog) through a needle that is left in place. This basal rate is adjustable, and therefore can be customized to meet variable needs over a 24‐hour period. When the patient takes in nutrition, a bolus of the same insulin is given, via the pump, at a dose that is appropriate to cover the nutritional intake. The advantages of CSII therapy are the capacity for precision and flexibility of the basal insulin delivery (compared to the use of a once‐daily or twice‐daily dose of long‐acting insulin analog), and the lack of a need to inject insulin boluses (which are delivered via the pump). This type of therapy is preferred by some diabetes patients, and although it is not highly prevalent in most areas, it is common enough that hospitalists must have a plan for managing it in their practices.

There are many barriers to the use of CSII in the hospital. Most of these barriers are related to the need for constant management of the pump. Most hospitalists and nurses do not have the expertise to manage this therapy in the hospital. Although the patient (or caregiver) might have the expertise to manage the pump, this is an acceptable option only if the patient is competent to manage the pump. Patient competence to use the pump must be formally assessed and documented, and the patient must agree to perform the many components of care related to managing the pump (eg, documenting the basal rate and boluses given, documenting BGs, providing tubing and other supplies).

Many hospitals currently choose a policy of converting insulin pump therapy to standard subcutaneous insulin treatment for most hospitalized patients. Usually the conversion of CSII to a physiologic subcutaneous insulin regimen (as detailed in this article) is fairly straightforwardthe basal insulin will be given as long‐acting, low‐peaking insulin, and nutritional and correction‐dose insulin can then be added as a rapid‐acting analog, in accord with the patient's needs.

Hospitals that admit a large number of insulin pump patients, or those that choose to use pumps routinely in the hospital, should create a formal policy for pump use.11 It has been suggested that the policy should assure that there is formal assessment of the patient's competence to manage the pump, that there is professional oversight of the pump management (usually via endocrinology and diabetes educator consultation), that contraindications for CSII use are clearly stated, and that there is a formal mechanism for engaging the patient and informing him of his roles and responsibilities (eg, a written agreement). The clinician must write insulin orders in the medical record that specify the basal and bolus insulin doses which are being used. Pump use may be limited to floors where nurses receive at least basic education in the principles of CSII pumps.

CARE TRANSITIONS IN THE HOSPITAL

CONCLUSIONS

Understanding the basic principles of the physiologic (basal, nutritional, and correction‐dose) insulin regimen will allow clinicians to formulate safe and effective insulin regimens in virtually any clinical situation. Simple steps can allow safe estimates of initial doses and titration toward glycemic goals. Additional information and case studies can be found in a Society of Hospital Medicine Task Force Educational Module,5 available online.

Additional resources for improving glycemic control in hospital patients are available online at the Glycemic Control Resource Room (http://www.hospitalmedicine.org/ResourceRoomRedesign/ GlycemicControl.cfm).

The delayed and variable absorption of subcutaneous (SC) insulin has always provided challenges for the rapid and predictable control of hyperglycemia in the acute care setting. Conversely, intravenous infusion of human regular insulin provides a continuous and essentially immediate delivery mechanism. Once in the circulation, insulin has a very short half‐life of about 5 to 7 minutes and a biological effect of about 20 minutes.1 Intravenous insulin infusions are well‐established in several acute care settings including hyperglycemic emergencies, perioperative glucose management, and glucose control during labor and delivery.2, 3

The beneficial effects seen in early trials of strict glycemic control involving intensive care unit (ICU) patients47 (particularly cardiac surgery patients) and guidelines for inpatient glycemic control8 stimulated widespread interest in adopting insulin infusion protocols (IIPs) focused on achieving strict glycemic targets. The initial enthusiasm has been tempered by uneven results in trials of tight glycemic control, concerns about the effects of excessive hypoglycemia, and the resources needed to implement and maintain an IIP.9 Although considerable controversy about the ideal glycemic target for different patient populations exists, and will likely continue for some time, this article is not a review of the evidence for supporting 1 glycemic target versus another. Regardless of the glycemic target chosen, a standardized algorithm and accompanying program of monitoring are widely endorsed for both safety and quality reasons.1014 Most medical centers are at least attempting to implement nurse‐driven protocols that have demonstrated better perfomance than SC regimens15 and physician‐driven insulin infusions.16, 17 In this article, we outline several variables in IIP design and implementation and endorse several aspects of design and implementation that will likely result in improved staff acceptance and, ultimately, a more safe and effective IIP.

PREPARING TO IMPLEMENT AN IIP

CHOOSING AN IIP FOR YOUR HOSPITAL

See Table 2 for a comparison of several features identified in selected published protocols.7, 2127 This is not a comprehensive list of all protocols found in the literature. Rather, the authors consider it representative of the various types of IIPs or best recognized IIPs in the literature. Note that there is variability in study population, the glucose targets, hypoglycemia, the time to reach the target, and the time spent in the target range. Other practical factors to consider in reviewing the literature and selecting an IIP design are the complexity of the protocol, the required process steps or calculations, the evidence for staff acceptance, and the level of resources supporting the published protocol.

ENHANCING THE DESIGN OF YOUR IIP

Once the improvement team has identified and examined current order sets and protocols in the context of the literature, we encourage consolidation of institutional insulin infusion orders into a common basic structure. This basic structure should be enhanced by incorporating a variety of elements designed to enhance the reliability of use and safety of the IIP. These design features are outlined in Table 3. Randomized trial evidence of the effectiveness of these design features are largely lacking, but they are well grounded in reliability principles and common experience, and have also been recommended by others.1013, 58

The orders should require a single physician signature and limited physician choices as the vehicle initiating the nurse‐driven protocol. The glycemic target range should be explicitly identified, and guidance for calling the physician and how to handle interruptions in nutrition should be embedded in the order set. Frequent monitoring of glucose levels is necessary for the safe infusion of insulin. Guidance for how often the monitoring is required must be explicit and included in the infusion order set, and standardization of documentation of the infusion rates and glucose values is highly desirable. IIPs that adjust based on the velocity of glucose change and insulin sensitivity are desirable. Certain elements may be more appropriate for some institutions than others, partly based on previous protocols and methods of practice. For example, the hypoglycemia protocol may be embedded or referred to as a separate standard of care with clear presence in the chart. The intended timing of conversion from IV to SC insulin should be included, but the actual method may be the subject of a separate order set. At other times, the conversion formula will be part of the initial intravenous order set.

IMPLEMENTATION: ADDRESSING SAFETY ISSUES

The use of insulin infusions comes with several potential hazards. Many of these potential complications can be proactively addressed, thereby minimizing accidental injuries to the patient on an insulin infusion.

IMPLEMENTATION: EDUCATING AND ENGAGING NURSING AND PHYSICIAN STAFF

Nursing staff generally bear the brunt of the burden on the front line of implementing intensive IIPs. Educational efforts for nurses should include the rationale for intensive insulin therapy and use of an IIP. Additionally, detailed, case‐based instruction on utilization of the IIP is required. Properly educated, nursing staff often become the strongest advocates of the IIP. In addition, they can frequently provide important input when situations arise that require troubleshooting. Regular feedback sessions early in implementation that address ease of use, clarity of orders, and difficulties encountered by nurses can be invaluable. Improvement teams need to provide frequent in‐service training and updates on the IIP selected after implementation. This is imperative to promote nursing acceptance and adherence to the IIP chosen, particularly with consideration for traveling nurses. The importance of nursing champions to design and carry out this work cannot be overstated. Educational programs focusing on the physician staff can also be very useful, particularly when focused on high‐volume physicians and influential thought leaders.

IMPLEMENTATION: ADDRESSING COMMON CLINICAL SITUATIONS

ASSESSING THE IMPACT OF YOUR EFFORTS: FOLLOW‐UP AND FOLLOW‐THROUGH

CONCLUSIONS

Insulin infusions are a powerful clinical tool in the inpatient setting to maintain glycemic control. Many IIPs have been developed and used successfully. The institutional challenge is to select, modify, and implement the IIP to reduce hyperglycemia and improve outcomes without excess hypoglycemia. In order to accomplish this goal safely and efficiently, standardized processes and collaboration between physicians, nurses, and pharmacists are needed. The keys to minimizing errors include developing a culture of safety and cooperation, back‐up checks, standardization, automation, and robust training for all those who are involved in the care of a patient on an insulin infusion. Although we encourage standardization and the use of protocols, providers always need to consider the unique clinical circumstances and potential problems presented by each individual patient. It is important to recognize the many barriers to successful implementation of an IIP, but strategies exist to overcome these. Finally, remember that the process does not end with the development phase. Continued review is paramount to success. Note variations in use, analyze them, and learn from them, in order to continually improve the process of care.

The delayed and variable absorption of subcutaneous (SC) insulin has always provided challenges for the rapid and predictable control of hyperglycemia in the acute care setting. Conversely, intravenous infusion of human regular insulin provides a continuous and essentially immediate delivery mechanism. Once in the circulation, insulin has a very short half‐life of about 5 to 7 minutes and a biological effect of about 20 minutes.1 Intravenous insulin infusions are well‐established in several acute care settings including hyperglycemic emergencies, perioperative glucose management, and glucose control during labor and delivery.2, 3

The beneficial effects seen in early trials of strict glycemic control involving intensive care unit (ICU) patients47 (particularly cardiac surgery patients) and guidelines for inpatient glycemic control8 stimulated widespread interest in adopting insulin infusion protocols (IIPs) focused on achieving strict glycemic targets. The initial enthusiasm has been tempered by uneven results in trials of tight glycemic control, concerns about the effects of excessive hypoglycemia, and the resources needed to implement and maintain an IIP.9 Although considerable controversy about the ideal glycemic target for different patient populations exists, and will likely continue for some time, this article is not a review of the evidence for supporting 1 glycemic target versus another. Regardless of the glycemic target chosen, a standardized algorithm and accompanying program of monitoring are widely endorsed for both safety and quality reasons.1014 Most medical centers are at least attempting to implement nurse‐driven protocols that have demonstrated better perfomance than SC regimens15 and physician‐driven insulin infusions.16, 17 In this article, we outline several variables in IIP design and implementation and endorse several aspects of design and implementation that will likely result in improved staff acceptance and, ultimately, a more safe and effective IIP.

PREPARING TO IMPLEMENT AN IIP