Patient Care

Clinical question: Is the use of beta blockers within 24 hours of coronary artery bypass grafting (CABG) surgery without recent myocardial infarction (MI) associated with decreased peri-operative mortality?

Background: Several retrospective observational studies suggest a reduction in peri-operative mortality with CABG surgery if beta blockers are administered prior to surgery. Although the use of beta blockers pre-operatively for CABG is now a quality measure, the use of pre-operative beta blockers is still controversial due to the results of more recent studies, with the observed benefit thought to be driven mainly by patients with recent MI.

Study design: Retrospective cohort analysis.

Setting: More than 1,100 U.S. hospitals.

Synopsis: The Society of Thoracic Surgeons’ National Adult Cardiac Surgery database identified 506,110 adult patients (without MI within 21 days) nonemergently undergoing CABG surgery. Beta blocker use was defined as receiving a beta blocker within 24 hours before surgery. Although most patients (86%) received beta blockers prior to surgery, there was no significant difference in operative mortality, permanent stroke, prolonged ventilation, and renal failure between patients receiving beta blockers and those who did not, although atrial fibrillation (Afib) was more common with pre-operative beta blocker use.

Bottom line: For patients undergoing nonemergent CABG surgery without recent MI, pre-operative beta blocker use is not associated with improved outcomes and is associated with slightly higher rates of Afib.

Citation: Brinkman W, Herbert MA, O’Brien S, et al. Preoperative beta-blocker use in coronary artery bypass grafting surgery: national database analysis. JAMA Intern Med. 2014;174(8):1320-1327.

Clinical question: Is the use of beta blockers within 24 hours of coronary artery bypass grafting (CABG) surgery without recent myocardial infarction (MI) associated with decreased peri-operative mortality?

Background: Several retrospective observational studies suggest a reduction in peri-operative mortality with CABG surgery if beta blockers are administered prior to surgery. Although the use of beta blockers pre-operatively for CABG is now a quality measure, the use of pre-operative beta blockers is still controversial due to the results of more recent studies, with the observed benefit thought to be driven mainly by patients with recent MI.

Study design: Retrospective cohort analysis.

Setting: More than 1,100 U.S. hospitals.

Synopsis: The Society of Thoracic Surgeons’ National Adult Cardiac Surgery database identified 506,110 adult patients (without MI within 21 days) nonemergently undergoing CABG surgery. Beta blocker use was defined as receiving a beta blocker within 24 hours before surgery. Although most patients (86%) received beta blockers prior to surgery, there was no significant difference in operative mortality, permanent stroke, prolonged ventilation, and renal failure between patients receiving beta blockers and those who did not, although atrial fibrillation (Afib) was more common with pre-operative beta blocker use.

Bottom line: For patients undergoing nonemergent CABG surgery without recent MI, pre-operative beta blocker use is not associated with improved outcomes and is associated with slightly higher rates of Afib.

Citation: Brinkman W, Herbert MA, O’Brien S, et al. Preoperative beta-blocker use in coronary artery bypass grafting surgery: national database analysis. JAMA Intern Med. 2014;174(8):1320-1327.

Clinical question: Is the use of beta blockers within 24 hours of coronary artery bypass grafting (CABG) surgery without recent myocardial infarction (MI) associated with decreased peri-operative mortality?

Background: Several retrospective observational studies suggest a reduction in peri-operative mortality with CABG surgery if beta blockers are administered prior to surgery. Although the use of beta blockers pre-operatively for CABG is now a quality measure, the use of pre-operative beta blockers is still controversial due to the results of more recent studies, with the observed benefit thought to be driven mainly by patients with recent MI.

Study design: Retrospective cohort analysis.

Setting: More than 1,100 U.S. hospitals.

Synopsis: The Society of Thoracic Surgeons’ National Adult Cardiac Surgery database identified 506,110 adult patients (without MI within 21 days) nonemergently undergoing CABG surgery. Beta blocker use was defined as receiving a beta blocker within 24 hours before surgery. Although most patients (86%) received beta blockers prior to surgery, there was no significant difference in operative mortality, permanent stroke, prolonged ventilation, and renal failure between patients receiving beta blockers and those who did not, although atrial fibrillation (Afib) was more common with pre-operative beta blocker use.

Bottom line: For patients undergoing nonemergent CABG surgery without recent MI, pre-operative beta blocker use is not associated with improved outcomes and is associated with slightly higher rates of Afib.

Citation: Brinkman W, Herbert MA, O’Brien S, et al. Preoperative beta-blocker use in coronary artery bypass grafting surgery: national database analysis. JAMA Intern Med. 2014;174(8):1320-1327.

Clinical question: Does the CAM-S, a modified version of the Confusion Assessment Method (CAM), which measures delirium severity, correlate with clinical outcomes?

Background: In 1990, Dr. Sharon Inouye developed the CAM, which is a common, standard measure to identify the presence of delirium. Although other scoring systems exist to quantify delirium severity, Dr. Inouye proposes an extension of the CAM (CAM-S) to measure delirium severity.

Study design: Validation analysis.

Setting: Three academic medical centers in the U.S.

Synopsis: Two validation cohorts of patients 70 years or older without dementia and moderate-to-high-risk of developing delirium during hospitalization were studied. The first cohort comprised 300 patients scheduled for elective, noncardiac surgery; the second cohort was made up of 250 patients admitted to an inpatient medical service. The CAM-S uses the same items as the original CAM and rates each symptom 0 for absent, 1 for mild, or 2 for marked; acute onset of fluctuation receives 0 (absent) or 1 (present). Higher CAM-S scores appear to correlate with various outcome measures, including increased length of stay, new nursing home placement, and 90-day mortality.

Bottom line: Higher scores on the CAM-S, a scoring system based on the CAM and designed to measure delirium severity, are associated with worse in-hospital and post-discharge outcomes.

Citation: Inouye SK, Kosar CM, Tommet D, et al. The CAM-S: development and validation of a new scoring system for delirium severity in 2 cohorts. Ann Intern Med. 2014;160(8):526-533.

Clinical question: Does the CAM-S, a modified version of the Confusion Assessment Method (CAM), which measures delirium severity, correlate with clinical outcomes?

Background: In 1990, Dr. Sharon Inouye developed the CAM, which is a common, standard measure to identify the presence of delirium. Although other scoring systems exist to quantify delirium severity, Dr. Inouye proposes an extension of the CAM (CAM-S) to measure delirium severity.

Study design: Validation analysis.

Setting: Three academic medical centers in the U.S.

Synopsis: Two validation cohorts of patients 70 years or older without dementia and moderate-to-high-risk of developing delirium during hospitalization were studied. The first cohort comprised 300 patients scheduled for elective, noncardiac surgery; the second cohort was made up of 250 patients admitted to an inpatient medical service. The CAM-S uses the same items as the original CAM and rates each symptom 0 for absent, 1 for mild, or 2 for marked; acute onset of fluctuation receives 0 (absent) or 1 (present). Higher CAM-S scores appear to correlate with various outcome measures, including increased length of stay, new nursing home placement, and 90-day mortality.

Bottom line: Higher scores on the CAM-S, a scoring system based on the CAM and designed to measure delirium severity, are associated with worse in-hospital and post-discharge outcomes.

Citation: Inouye SK, Kosar CM, Tommet D, et al. The CAM-S: development and validation of a new scoring system for delirium severity in 2 cohorts. Ann Intern Med. 2014;160(8):526-533.

Clinical question: Does the CAM-S, a modified version of the Confusion Assessment Method (CAM), which measures delirium severity, correlate with clinical outcomes?

Background: In 1990, Dr. Sharon Inouye developed the CAM, which is a common, standard measure to identify the presence of delirium. Although other scoring systems exist to quantify delirium severity, Dr. Inouye proposes an extension of the CAM (CAM-S) to measure delirium severity.

Study design: Validation analysis.

Setting: Three academic medical centers in the U.S.

Synopsis: Two validation cohorts of patients 70 years or older without dementia and moderate-to-high-risk of developing delirium during hospitalization were studied. The first cohort comprised 300 patients scheduled for elective, noncardiac surgery; the second cohort was made up of 250 patients admitted to an inpatient medical service. The CAM-S uses the same items as the original CAM and rates each symptom 0 for absent, 1 for mild, or 2 for marked; acute onset of fluctuation receives 0 (absent) or 1 (present). Higher CAM-S scores appear to correlate with various outcome measures, including increased length of stay, new nursing home placement, and 90-day mortality.

Bottom line: Higher scores on the CAM-S, a scoring system based on the CAM and designed to measure delirium severity, are associated with worse in-hospital and post-discharge outcomes.

Citation: Inouye SK, Kosar CM, Tommet D, et al. The CAM-S: development and validation of a new scoring system for delirium severity in 2 cohorts. Ann Intern Med. 2014;160(8):526-533.

Clinical question: What are the mortality benefits and bleeding risks associated with thrombolytic therapy, compared with other anticoagulants, in pulmonary embolism (PE)?

Background: Thrombolytics are not routinely administered for PE but can be considered in patients with hemodynamic instability with massive PE and those not responding to anticoagulation.

Study design: Meta-analysis.

Setting: Sixteen randomized clinical trials (RCTs) occurring in a variety of settings.

Synopsis: Trials involving 2,115 patients (thrombolytic therapy cohort 1,061; anticoagulation cohort 1,054) with PE were studied, with special attention given to those patients with intermediate risk PEs defined by subclinical cardiovascular compromise. Thrombolytics were compared with low molecular weight heparin, unfractionated heparin, vitamin K antagonists, and fondaparinux. The primary outcomes were all-cause mortality and major bleeding. Secondary outcomes included risk of recurrence of the PE and intracranial hemorrhage.

Thrombolytic therapy was associated with lower all-cause mortality and with higher risk of bleeding. There was a 9.24% rate of major bleeding in the thrombolytic therapy cohort and a 3.42% rate in the anticoagulation cohort. Intracranial hemorrhage was greater in the thrombolytic therapy cohort (1.46% vs. 0.19%). Patients with intermediate risk PE had greater major bleeding rate (7.74% vs. 2.25%) and lower mortality (1.39% vs. 2.92%) with thrombolytics compared to anticoagulation. A net clinical benefit calculation (mortality benefit accounting for intracranial hemorrhage risk) was performed and demonstrated a net clinical benefit of 0.81% (95% CI, 0.65%-1.01%) for those patients who received thrombolytics versus other anticoagulation.

Bottom line: This study suggested a mortality benefit of thrombolytics overall, including those patients with intermediate risk PE.

Citation: Chatterjee S, Chakraborty A, Weinberg I, et al. Thrombolysis for pulmonary embolism and risk of all-cause mortality, major bleeding, and intracranial hemorrhage: a meta-analysis. JAMA. 2014;311(23):2414-2421.

Clinical question: What are the mortality benefits and bleeding risks associated with thrombolytic therapy, compared with other anticoagulants, in pulmonary embolism (PE)?

Background: Thrombolytics are not routinely administered for PE but can be considered in patients with hemodynamic instability with massive PE and those not responding to anticoagulation.

Study design: Meta-analysis.

Setting: Sixteen randomized clinical trials (RCTs) occurring in a variety of settings.

Synopsis: Trials involving 2,115 patients (thrombolytic therapy cohort 1,061; anticoagulation cohort 1,054) with PE were studied, with special attention given to those patients with intermediate risk PEs defined by subclinical cardiovascular compromise. Thrombolytics were compared with low molecular weight heparin, unfractionated heparin, vitamin K antagonists, and fondaparinux. The primary outcomes were all-cause mortality and major bleeding. Secondary outcomes included risk of recurrence of the PE and intracranial hemorrhage.

Thrombolytic therapy was associated with lower all-cause mortality and with higher risk of bleeding. There was a 9.24% rate of major bleeding in the thrombolytic therapy cohort and a 3.42% rate in the anticoagulation cohort. Intracranial hemorrhage was greater in the thrombolytic therapy cohort (1.46% vs. 0.19%). Patients with intermediate risk PE had greater major bleeding rate (7.74% vs. 2.25%) and lower mortality (1.39% vs. 2.92%) with thrombolytics compared to anticoagulation. A net clinical benefit calculation (mortality benefit accounting for intracranial hemorrhage risk) was performed and demonstrated a net clinical benefit of 0.81% (95% CI, 0.65%-1.01%) for those patients who received thrombolytics versus other anticoagulation.

Bottom line: This study suggested a mortality benefit of thrombolytics overall, including those patients with intermediate risk PE.

Citation: Chatterjee S, Chakraborty A, Weinberg I, et al. Thrombolysis for pulmonary embolism and risk of all-cause mortality, major bleeding, and intracranial hemorrhage: a meta-analysis. JAMA. 2014;311(23):2414-2421.

Clinical question: What are the mortality benefits and bleeding risks associated with thrombolytic therapy, compared with other anticoagulants, in pulmonary embolism (PE)?

Background: Thrombolytics are not routinely administered for PE but can be considered in patients with hemodynamic instability with massive PE and those not responding to anticoagulation.

Study design: Meta-analysis.

Setting: Sixteen randomized clinical trials (RCTs) occurring in a variety of settings.

Synopsis: Trials involving 2,115 patients (thrombolytic therapy cohort 1,061; anticoagulation cohort 1,054) with PE were studied, with special attention given to those patients with intermediate risk PEs defined by subclinical cardiovascular compromise. Thrombolytics were compared with low molecular weight heparin, unfractionated heparin, vitamin K antagonists, and fondaparinux. The primary outcomes were all-cause mortality and major bleeding. Secondary outcomes included risk of recurrence of the PE and intracranial hemorrhage.

Thrombolytic therapy was associated with lower all-cause mortality and with higher risk of bleeding. There was a 9.24% rate of major bleeding in the thrombolytic therapy cohort and a 3.42% rate in the anticoagulation cohort. Intracranial hemorrhage was greater in the thrombolytic therapy cohort (1.46% vs. 0.19%). Patients with intermediate risk PE had greater major bleeding rate (7.74% vs. 2.25%) and lower mortality (1.39% vs. 2.92%) with thrombolytics compared to anticoagulation. A net clinical benefit calculation (mortality benefit accounting for intracranial hemorrhage risk) was performed and demonstrated a net clinical benefit of 0.81% (95% CI, 0.65%-1.01%) for those patients who received thrombolytics versus other anticoagulation.

Bottom line: This study suggested a mortality benefit of thrombolytics overall, including those patients with intermediate risk PE.

Citation: Chatterjee S, Chakraborty A, Weinberg I, et al. Thrombolysis for pulmonary embolism and risk of all-cause mortality, major bleeding, and intracranial hemorrhage: a meta-analysis. JAMA. 2014;311(23):2414-2421.

Clinical question: Which interventions are most effective to prevent 30-day readmissions in medical or surgical patients?

Background: Preventing early readmissions has become a national priority. This study set out to determine which intervention had the largest impact on the prevention of early readmission.

Study design: Meta-analysis.

Setting: Forty-seven studies in multiple locations.

Synopsis: This study evaluated 47 randomized trials that assessed the effectiveness of peri-discharge interventions on the risk of all-cause or unplanned 30-day readmissions for medical and surgical patients. Outcomes included unplanned readmissions, all-cause readmissions, and a composite of unplanned and all-cause readmissions plus out-of-hospital deaths.

The included studies reported up to seven methods of preventing readmissions, including involvement of case management, home visits, education of patients, and self-care support. In 42 trials reporting readmission rates, the pooled relative risk of readmission was 0.82 (95 % CI, 0.73-0.91; P<0.001) within 30 days.

Multiple subgroup analyses noted that the most effective interventions on hospital readmission were those that were more complex and those that sought to augment patient capacity to access and enact dependable post-discharge care.

Limitations included single-center academic studies, lack of standard for dealing with missing data, existence of publication bias, and differing methods used to evaluate intervention effects.

Bottom line: This study was the largest of its kind, to date, and suggests that the interventions analyzed in this study, although complex (e.g. enhancing capacity for self-care at home), were efficacious in reducing 30-day readmissions.

Citation: Leppin AL, Gionfriddo MR, Kessler M, et al. Preventing 30-day hospital readmissions: a systematic review and meta-analysis of randomized trials. JAMA Intern Med. 2014;174(7):1095-1107.

Clinical question: Which interventions are most effective to prevent 30-day readmissions in medical or surgical patients?

Background: Preventing early readmissions has become a national priority. This study set out to determine which intervention had the largest impact on the prevention of early readmission.

Study design: Meta-analysis.

Setting: Forty-seven studies in multiple locations.

Synopsis: This study evaluated 47 randomized trials that assessed the effectiveness of peri-discharge interventions on the risk of all-cause or unplanned 30-day readmissions for medical and surgical patients. Outcomes included unplanned readmissions, all-cause readmissions, and a composite of unplanned and all-cause readmissions plus out-of-hospital deaths.

The included studies reported up to seven methods of preventing readmissions, including involvement of case management, home visits, education of patients, and self-care support. In 42 trials reporting readmission rates, the pooled relative risk of readmission was 0.82 (95 % CI, 0.73-0.91; P<0.001) within 30 days.

Multiple subgroup analyses noted that the most effective interventions on hospital readmission were those that were more complex and those that sought to augment patient capacity to access and enact dependable post-discharge care.

Limitations included single-center academic studies, lack of standard for dealing with missing data, existence of publication bias, and differing methods used to evaluate intervention effects.

Bottom line: This study was the largest of its kind, to date, and suggests that the interventions analyzed in this study, although complex (e.g. enhancing capacity for self-care at home), were efficacious in reducing 30-day readmissions.

Citation: Leppin AL, Gionfriddo MR, Kessler M, et al. Preventing 30-day hospital readmissions: a systematic review and meta-analysis of randomized trials. JAMA Intern Med. 2014;174(7):1095-1107.

Clinical question: Which interventions are most effective to prevent 30-day readmissions in medical or surgical patients?

Background: Preventing early readmissions has become a national priority. This study set out to determine which intervention had the largest impact on the prevention of early readmission.

Study design: Meta-analysis.

Setting: Forty-seven studies in multiple locations.

Synopsis: This study evaluated 47 randomized trials that assessed the effectiveness of peri-discharge interventions on the risk of all-cause or unplanned 30-day readmissions for medical and surgical patients. Outcomes included unplanned readmissions, all-cause readmissions, and a composite of unplanned and all-cause readmissions plus out-of-hospital deaths.

The included studies reported up to seven methods of preventing readmissions, including involvement of case management, home visits, education of patients, and self-care support. In 42 trials reporting readmission rates, the pooled relative risk of readmission was 0.82 (95 % CI, 0.73-0.91; P<0.001) within 30 days.

Multiple subgroup analyses noted that the most effective interventions on hospital readmission were those that were more complex and those that sought to augment patient capacity to access and enact dependable post-discharge care.

Limitations included single-center academic studies, lack of standard for dealing with missing data, existence of publication bias, and differing methods used to evaluate intervention effects.

Bottom line: This study was the largest of its kind, to date, and suggests that the interventions analyzed in this study, although complex (e.g. enhancing capacity for self-care at home), were efficacious in reducing 30-day readmissions.

Citation: Leppin AL, Gionfriddo MR, Kessler M, et al. Preventing 30-day hospital readmissions: a systematic review and meta-analysis of randomized trials. JAMA Intern Med. 2014;174(7):1095-1107.

High rate of durable responses to pembrolizumab in metastatic melanoma

High rate of durable responses to pembrolizumab in metastatic melanoma

High rate of durable responses to pembrolizumab in metastatic melanoma

Case

A 77-year-old woman with a history of stroke five months prior, bileaflet aortic valve prosthesis, hypertension, and insulin-dependent diabetes is admitted for laparoscopy with lysis of adhesions. The patient stopped her warfarin 10 days prior to admission and initiated enoxaparin five days later. When should the enoxaparin be discontinued?

Intra-operatively, the surgeon converted the case to an open laparotomy for a bowel resection with re-anastomosis; post-operatively, when should the hospitalist reinitiate warfarin and enoxaparin?

Background

Many patients receive chronic oral anticoagulant therapy to minimize their long-term risk of thromboembolic disease. Hospitalists and outpatient providers often care for such patients who need to undergo a medical procedure or operation. The risk of bleeding associated with the medical procedure necessitates an interruption in the patient’s chronic oral anticoagulant therapy. In this scenario, providers are faced with several therapeutic decisions:

• How soon before the procedure should patients stop taking oral anticoagulant?
• During the period of time when the patient is not taking chronic oral anticoagulant, should the patient receive parenteral bridging anticoagulant therapy?
• After the procedure, when should patients restart chronic oral anticoagulant therapy?

‘Bridge’ anticoagulant therapy is the administration of a short-acting parenteral anticoagulant during the peri-operative period, when the patient is not taking chronic oral anticoagulant.¹ The intent of bridge anticoagulant therapy is to minimize both the risk of thromboembolic events and the risk of bleeding during the peri-operative period. Bridging anticoagulant therapy is appropriate for some but not all patients undergoing medical procedures.

The Data

When to discontinue warfarin? Warfarin, the most commonly prescribed oral anticoagulant, achieves its therapeutic effects by antagonizing the actions of endogenous vitamin K-dependent coagulation factors. The decision on when to stop warfarin prior to surgery is dependent on the regeneration time of coagulation factors following the discontinuation of warfarin therapy. Although warfarin’s half-life is typically 36-42 hours, its therapeutic effects typically last up to five days in healthy subjects and often longer in elderly patients.²

Current guidelines recommend the discontinuation of warfarin at least five days prior to surgery (Grade 1C recommendation).³ Despite this recommendation, approximately 7% of patients will still have an international normalized ratio (INR) >1.5 after not taking warfarin for five days.⁴ For this reason, the guidelines recommend that all patients have their INR checked on the day of surgery. For those patients with an INR of 1.5 to 1.9 on the day prior to surgery, there is evidence to show that administration of 1 mg of vitamin K will lower the INR to 1.4 in greater than 90% of cases.⁵

Assessment of peri-procedural thrombotic risk. Knowledge of a patient’s past medical history is critical in helping providers stratify the patient’s peri-procedural thrombotic risk. According to the 2012 American College of Chest Physicians (ACCP) guidelines, a history of atrial fibrillation (Afib), mechanical heart valve(s), and previous VTE are independent risk factors for peri-procedural thrombotic events.³ Hospitalists may risk-stratify their patients based on the anticipated annualized rate of thrombosis or embolization: <5%, 5%-10%, or >15% for the respective low, medium, and high-risk groups.⁶

Patients with Afib history. For these patients, the CHADS2 score helps to stratify the risk of peri-procedural thrombosis. Low risk is defined as a CHADS2 score of zero to two, assuming that the two points were not scored for transient ischemic attack (TIA) or cerebrovascular accident (CVA). Any patient with a TIA or CVA within the previous three months is automatically considered high risk. Medium risk is a score of three or four.

In addition to the aforementioned TIA or CVA within the prior three months, high-risk patients also include those with a CHADS2 score of five or six or any patient with a history of rheumatic heart disease.³ Patients with CHADS2 scores less than five but with a TIA or CVA greater than three months in the past are high risk.⁷

Presence of mechanical heart valve(s). For patients with a mechanical heart valve, knowledge of the valve type and location is essential to assist hospitalists in stratifying the risk of peri-procedural thrombosis. The current ACCP guidelines consider patients with bileaflet aortic valve prostheses without additional risk factors for stroke or atrial fibrillation to be low risk.³

The guidelines define the following characteristics as medium risk for patients: the presence of a bileaflet valve with additional risk factors for stroke such as atrial fibrillation, age greater than 75, prior CVA (more than six months prior), hypertension, diabetes mellitus, or congestive heart failure.

Patients at high risk include those with aortic valve prosthesis with a caged-ball or tilting disc, patients with mitral valve prosthesis, and those with a mechanical valve with CVA or TIA during the prior six months.⁷

History of previous VTE. For these patients, the duration of time that has passed since their last VTE event is an important factor in helping to stratify their risk for peri-procedural thrombosis. Hospitalists should consider patients low risk if they had VTE more than one year prior to the procedure.

Medium-risk patients are those with VTE events in the preceding three to twelve months, those with recurrent VTE, those with active cancer who have received cancer therapy within six months, or patients with non-severe thrombophilias (e.g. heterogenous factor V Leiden or prothrombin gene mutation).

Hospitalists should identify high-risk patients as those with VTE that has occurred within three months or those with severe thrombophilias such as Protein C or S deficiency, antithrombin III deficiency, or antiphospholipid antibody syndrome.

Assessment of procedure-related thrombotic risk. The type of anticipated procedure itself conveys peri-procedural thrombotic risk. For example, heart valve replacement, carotid endarterectomy, or other major vascular surgeries automatically stratify patients in the high-risk category, regardless of underlying medication condition.

Assessment of bleeding risk. Hospitalists must identify any preexisting bleeding risk factors (i.e., hemophilias or thrombocytopenia) in addition to the post-procedural bleeding risks. Risk factors for increased post-procedural bleeding include: major surgery with extensive tissue injury, procedures involving highly vascularized organs, removal of large colonic polyps, urological procedures, placement of implantable cardioverter-defibrillator/pacemakers, and procedures at sites where minor bleeding would be clinically devastating, such as the brain or spine.³

Thus, communication with the proceduralist or surgeon regarding the anticipated bleeding risk is vital.

Should the patient receive bridging anticoagulation? Patients considered high risk for peri-procedural thrombosis should receive peri-procedural bridging anticoagulation therapy, while those considered low risk should not. For patients with a moderate peri-procedural risk of thrombosis, hospitalists should base the decision on individual and anticipated pre-surgical/procedural thrombotic risks.

Recent evidence suggests that bridging anticoagulation should be avoided in patients undergoing procedures with high bleeding risk who are not at high thromboembolic risk.⁸

Selection and pre-operative discontinuation of bridging medication. Current ACCP guidelines only support the use of unfractionated heparin (UFH) or low molecular weight heparin (LMWH) as bridging anticoagulants.³ Evidence supports the use of either intravenous UFH (goal aPTT 1.5 to two times control aPTT) or enoxaparin (1 mg/kg BID or 1.5 mg/kg once daily).⁹ UFH is preferred over LMWH in patients with chronic kidney disease stage IV or V due to a more predictable pharmacokinetic profile.

Clinicians should initiate a bridge when a patient’s INR falls to less than 2.0 and discontinue the UFH bridge four to six hours prior to the procedure.¹⁰ The recent update to the guidelines now states that LMWH should be discontinued 24, instead of 12, hours prior to the procedure.³

When to restart UHF or LMWH bridge post-procedure. The type of procedure being performed dictates when bridging anticoagulation should resume. In patients who have undergone surgeries that involve high bleeding risk, LMWH should not be administered until 48-72 hours post-surgery (Grade 2C evidence).³ For those patients undergoing surgeries with low bleeding risk, bridging should be resumed approximately 24 hours after the procedure.

Of note, enoxaparin administered in one single daily dose, as compared to divided doses, is associated with a greater risk of post-operative bleeding. UFH bridging should resume post-operatively without a bolus dose at 24 hours in low-risk bleeding cases or 48-72 hours in high-risk bleeding cases (Grade 2C evidence).³

On occasion, unanticipated adjustments to surgical cases—or complications—change the previously determined post-operative bleeding risk. In these instances, the hospitalist and surgeon/proceduralist should review the case and reassess the bleeding risk prior to employing bridging anticoagulation protocols.

When to restart long-term vitamin K antagonists (VKA) post-procedure. In most instances, regardless of pre-operative bleeding risk stratification, the resumption of VKA may occur once post-operative hemostasis has been achieved and the patient has been instructed to resume eating by the proceduralist or surgeon. This most often occurs on the calendar day following surgery, because it takes approximately five days for an INR to achieve therapeutic levels.

Back to the Case

The patient’s history of prosthetic valve with stroke within the preceding six months stratified her to a high thrombotic risk category. Given the high risk of thrombosis, the decision was made to bridge with LMWH. The hospitalist discontinued LMWH 24 hours prior to surgery, and INR was checked on the morning of the procedure.

Although the patient underwent the operation without significant bleeding, the adjustment from an exploratory laparoscopy to an open laparotomy increased her post-operative bleeding risk from medium to high. Therefore, bridging anticoagulation with LMWH was resumed no sooner than 48 hours after the operation. Her warfarin was restarted on the day following surgery, once she resumed her diet.

Bottom Line

Hospitalists must understand both the pre- and post-procedure thrombotic risks, as well as the pre- and post-procedural bleeding risks, when determining the selection and logistics of initiation and cessation of antithrombotic bridging for inpatients.

Drs. McCormick, Carbo, and Li are hospitalists at Beth Israel Deaconess Medical Center in Boston. Dr. Kerbel is a hospitalist at the University of California Los Angeles.

References

1. BRIDGE Study Investigators. Bridging anticoagulation: is it needed when warfarin is interrupted around the time of a surgery or procedure? Circulation. 2012;125(12):e496-498.
2. Ansell J, Hirsh J, Hylek E, Jacobson A, Crowther M, Palareti G. Pharmacology and management of the vitamin K antagonists: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition). Chest. 2008;133(6 Suppl):160S-198S.
3. Douketis JD, Spyropoulos AC, Spencer FA, et al. Perioperative management of antithrombotic therapy: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines. Chest. 2012;141(2 Suppl):e326S-350S.
4. Kovacs MJ, Kearon C, Rodger M, et al. Single-arm study of bridging therapy with low-molecular-weight heparin for patients at risk of arterial embolism who require temporary interruption of warfarin. Circulation. 2004;110(12):1658-1663.
5. Woods K, Douketis JD, Kathirgamanathan K, Yi Q, Crowther MA. Low-dose oral vitamin K to normalize the international normalized ratio prior to surgery in patients who require temporary interruption of warfarin. J Thromb Thrombolysis. 2007;24(2):93-97.
6. Ortel TL. Perioperative management of patients on chronic antithrombotic therapy. Blood. 2012;120(24):4699-4705.
7. Kaatz S, Douketis JD, Zhou H, Gage BF, White RH. Risk of stroke after surgery in patients with and without chronic atrial fibrillation. J Thromb Haemost. 2010;8(5):884-890.
8. Siegal D, Yudin J, Kaatz S, Douketis JD, Lim W, Spyropoulos AC. Periprocedural heparin bridging in patients receiving vitamin K antagonists: systematic review and meta-analysis of bleeding and thromboembolic rates. Circulation. 2012;126(13):1630-1639.
9. Lee AY, Levine MN, Baker RI, et al. Low-molecular-weight heparin versus a coumarin for the prevention of recurrent venous thromboembolism in patients with cancer. N Engl J Med. 2003;349(2):146-153.
10. Hirsh J, Raschke R. Heparin and low-molecular-weight heparin: the Seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy. Chest. 2004;126(3 Suppl):188S-203S.

Case

A 77-year-old woman with a history of stroke five months prior, bileaflet aortic valve prosthesis, hypertension, and insulin-dependent diabetes is admitted for laparoscopy with lysis of adhesions. The patient stopped her warfarin 10 days prior to admission and initiated enoxaparin five days later. When should the enoxaparin be discontinued?

Intra-operatively, the surgeon converted the case to an open laparotomy for a bowel resection with re-anastomosis; post-operatively, when should the hospitalist reinitiate warfarin and enoxaparin?

Background

Many patients receive chronic oral anticoagulant therapy to minimize their long-term risk of thromboembolic disease. Hospitalists and outpatient providers often care for such patients who need to undergo a medical procedure or operation. The risk of bleeding associated with the medical procedure necessitates an interruption in the patient’s chronic oral anticoagulant therapy. In this scenario, providers are faced with several therapeutic decisions:

• How soon before the procedure should patients stop taking oral anticoagulant?
• During the period of time when the patient is not taking chronic oral anticoagulant, should the patient receive parenteral bridging anticoagulant therapy?
• After the procedure, when should patients restart chronic oral anticoagulant therapy?

‘Bridge’ anticoagulant therapy is the administration of a short-acting parenteral anticoagulant during the peri-operative period, when the patient is not taking chronic oral anticoagulant.¹ The intent of bridge anticoagulant therapy is to minimize both the risk of thromboembolic events and the risk of bleeding during the peri-operative period. Bridging anticoagulant therapy is appropriate for some but not all patients undergoing medical procedures.

The Data

When to discontinue warfarin? Warfarin, the most commonly prescribed oral anticoagulant, achieves its therapeutic effects by antagonizing the actions of endogenous vitamin K-dependent coagulation factors. The decision on when to stop warfarin prior to surgery is dependent on the regeneration time of coagulation factors following the discontinuation of warfarin therapy. Although warfarin’s half-life is typically 36-42 hours, its therapeutic effects typically last up to five days in healthy subjects and often longer in elderly patients.²

Current guidelines recommend the discontinuation of warfarin at least five days prior to surgery (Grade 1C recommendation).³ Despite this recommendation, approximately 7% of patients will still have an international normalized ratio (INR) >1.5 after not taking warfarin for five days.⁴ For this reason, the guidelines recommend that all patients have their INR checked on the day of surgery. For those patients with an INR of 1.5 to 1.9 on the day prior to surgery, there is evidence to show that administration of 1 mg of vitamin K will lower the INR to 1.4 in greater than 90% of cases.⁵

Assessment of peri-procedural thrombotic risk. Knowledge of a patient’s past medical history is critical in helping providers stratify the patient’s peri-procedural thrombotic risk. According to the 2012 American College of Chest Physicians (ACCP) guidelines, a history of atrial fibrillation (Afib), mechanical heart valve(s), and previous VTE are independent risk factors for peri-procedural thrombotic events.³ Hospitalists may risk-stratify their patients based on the anticipated annualized rate of thrombosis or embolization: <5%, 5%-10%, or >15% for the respective low, medium, and high-risk groups.⁶

Patients with Afib history. For these patients, the CHADS2 score helps to stratify the risk of peri-procedural thrombosis. Low risk is defined as a CHADS2 score of zero to two, assuming that the two points were not scored for transient ischemic attack (TIA) or cerebrovascular accident (CVA). Any patient with a TIA or CVA within the previous three months is automatically considered high risk. Medium risk is a score of three or four.

In addition to the aforementioned TIA or CVA within the prior three months, high-risk patients also include those with a CHADS2 score of five or six or any patient with a history of rheumatic heart disease.³ Patients with CHADS2 scores less than five but with a TIA or CVA greater than three months in the past are high risk.⁷

Presence of mechanical heart valve(s). For patients with a mechanical heart valve, knowledge of the valve type and location is essential to assist hospitalists in stratifying the risk of peri-procedural thrombosis. The current ACCP guidelines consider patients with bileaflet aortic valve prostheses without additional risk factors for stroke or atrial fibrillation to be low risk.³

The guidelines define the following characteristics as medium risk for patients: the presence of a bileaflet valve with additional risk factors for stroke such as atrial fibrillation, age greater than 75, prior CVA (more than six months prior), hypertension, diabetes mellitus, or congestive heart failure.

Patients at high risk include those with aortic valve prosthesis with a caged-ball or tilting disc, patients with mitral valve prosthesis, and those with a mechanical valve with CVA or TIA during the prior six months.⁷

History of previous VTE. For these patients, the duration of time that has passed since their last VTE event is an important factor in helping to stratify their risk for peri-procedural thrombosis. Hospitalists should consider patients low risk if they had VTE more than one year prior to the procedure.

Medium-risk patients are those with VTE events in the preceding three to twelve months, those with recurrent VTE, those with active cancer who have received cancer therapy within six months, or patients with non-severe thrombophilias (e.g. heterogenous factor V Leiden or prothrombin gene mutation).

Hospitalists should identify high-risk patients as those with VTE that has occurred within three months or those with severe thrombophilias such as Protein C or S deficiency, antithrombin III deficiency, or antiphospholipid antibody syndrome.

Assessment of procedure-related thrombotic risk. The type of anticipated procedure itself conveys peri-procedural thrombotic risk. For example, heart valve replacement, carotid endarterectomy, or other major vascular surgeries automatically stratify patients in the high-risk category, regardless of underlying medication condition.

Assessment of bleeding risk. Hospitalists must identify any preexisting bleeding risk factors (i.e., hemophilias or thrombocytopenia) in addition to the post-procedural bleeding risks. Risk factors for increased post-procedural bleeding include: major surgery with extensive tissue injury, procedures involving highly vascularized organs, removal of large colonic polyps, urological procedures, placement of implantable cardioverter-defibrillator/pacemakers, and procedures at sites where minor bleeding would be clinically devastating, such as the brain or spine.³

Thus, communication with the proceduralist or surgeon regarding the anticipated bleeding risk is vital.

Should the patient receive bridging anticoagulation? Patients considered high risk for peri-procedural thrombosis should receive peri-procedural bridging anticoagulation therapy, while those considered low risk should not. For patients with a moderate peri-procedural risk of thrombosis, hospitalists should base the decision on individual and anticipated pre-surgical/procedural thrombotic risks.

Recent evidence suggests that bridging anticoagulation should be avoided in patients undergoing procedures with high bleeding risk who are not at high thromboembolic risk.⁸

Selection and pre-operative discontinuation of bridging medication. Current ACCP guidelines only support the use of unfractionated heparin (UFH) or low molecular weight heparin (LMWH) as bridging anticoagulants.³ Evidence supports the use of either intravenous UFH (goal aPTT 1.5 to two times control aPTT) or enoxaparin (1 mg/kg BID or 1.5 mg/kg once daily).⁹ UFH is preferred over LMWH in patients with chronic kidney disease stage IV or V due to a more predictable pharmacokinetic profile.

Clinicians should initiate a bridge when a patient’s INR falls to less than 2.0 and discontinue the UFH bridge four to six hours prior to the procedure.¹⁰ The recent update to the guidelines now states that LMWH should be discontinued 24, instead of 12, hours prior to the procedure.³

When to restart UHF or LMWH bridge post-procedure. The type of procedure being performed dictates when bridging anticoagulation should resume. In patients who have undergone surgeries that involve high bleeding risk, LMWH should not be administered until 48-72 hours post-surgery (Grade 2C evidence).³ For those patients undergoing surgeries with low bleeding risk, bridging should be resumed approximately 24 hours after the procedure.

Of note, enoxaparin administered in one single daily dose, as compared to divided doses, is associated with a greater risk of post-operative bleeding. UFH bridging should resume post-operatively without a bolus dose at 24 hours in low-risk bleeding cases or 48-72 hours in high-risk bleeding cases (Grade 2C evidence).³

On occasion, unanticipated adjustments to surgical cases—or complications—change the previously determined post-operative bleeding risk. In these instances, the hospitalist and surgeon/proceduralist should review the case and reassess the bleeding risk prior to employing bridging anticoagulation protocols.

When to restart long-term vitamin K antagonists (VKA) post-procedure. In most instances, regardless of pre-operative bleeding risk stratification, the resumption of VKA may occur once post-operative hemostasis has been achieved and the patient has been instructed to resume eating by the proceduralist or surgeon. This most often occurs on the calendar day following surgery, because it takes approximately five days for an INR to achieve therapeutic levels.

Back to the Case

The patient’s history of prosthetic valve with stroke within the preceding six months stratified her to a high thrombotic risk category. Given the high risk of thrombosis, the decision was made to bridge with LMWH. The hospitalist discontinued LMWH 24 hours prior to surgery, and INR was checked on the morning of the procedure.

Although the patient underwent the operation without significant bleeding, the adjustment from an exploratory laparoscopy to an open laparotomy increased her post-operative bleeding risk from medium to high. Therefore, bridging anticoagulation with LMWH was resumed no sooner than 48 hours after the operation. Her warfarin was restarted on the day following surgery, once she resumed her diet.

Bottom Line

Hospitalists must understand both the pre- and post-procedure thrombotic risks, as well as the pre- and post-procedural bleeding risks, when determining the selection and logistics of initiation and cessation of antithrombotic bridging for inpatients.

Drs. McCormick, Carbo, and Li are hospitalists at Beth Israel Deaconess Medical Center in Boston. Dr. Kerbel is a hospitalist at the University of California Los Angeles.

References

1. BRIDGE Study Investigators. Bridging anticoagulation: is it needed when warfarin is interrupted around the time of a surgery or procedure? Circulation. 2012;125(12):e496-498.
2. Ansell J, Hirsh J, Hylek E, Jacobson A, Crowther M, Palareti G. Pharmacology and management of the vitamin K antagonists: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition). Chest. 2008;133(6 Suppl):160S-198S.
3. Douketis JD, Spyropoulos AC, Spencer FA, et al. Perioperative management of antithrombotic therapy: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines. Chest. 2012;141(2 Suppl):e326S-350S.
4. Kovacs MJ, Kearon C, Rodger M, et al. Single-arm study of bridging therapy with low-molecular-weight heparin for patients at risk of arterial embolism who require temporary interruption of warfarin. Circulation. 2004;110(12):1658-1663.
5. Woods K, Douketis JD, Kathirgamanathan K, Yi Q, Crowther MA. Low-dose oral vitamin K to normalize the international normalized ratio prior to surgery in patients who require temporary interruption of warfarin. J Thromb Thrombolysis. 2007;24(2):93-97.
6. Ortel TL. Perioperative management of patients on chronic antithrombotic therapy. Blood. 2012;120(24):4699-4705.
7. Kaatz S, Douketis JD, Zhou H, Gage BF, White RH. Risk of stroke after surgery in patients with and without chronic atrial fibrillation. J Thromb Haemost. 2010;8(5):884-890.
8. Siegal D, Yudin J, Kaatz S, Douketis JD, Lim W, Spyropoulos AC. Periprocedural heparin bridging in patients receiving vitamin K antagonists: systematic review and meta-analysis of bleeding and thromboembolic rates. Circulation. 2012;126(13):1630-1639.
9. Lee AY, Levine MN, Baker RI, et al. Low-molecular-weight heparin versus a coumarin for the prevention of recurrent venous thromboembolism in patients with cancer. N Engl J Med. 2003;349(2):146-153.
10. Hirsh J, Raschke R. Heparin and low-molecular-weight heparin: the Seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy. Chest. 2004;126(3 Suppl):188S-203S.

Case

A 77-year-old woman with a history of stroke five months prior, bileaflet aortic valve prosthesis, hypertension, and insulin-dependent diabetes is admitted for laparoscopy with lysis of adhesions. The patient stopped her warfarin 10 days prior to admission and initiated enoxaparin five days later. When should the enoxaparin be discontinued?

Intra-operatively, the surgeon converted the case to an open laparotomy for a bowel resection with re-anastomosis; post-operatively, when should the hospitalist reinitiate warfarin and enoxaparin?

Background

Many patients receive chronic oral anticoagulant therapy to minimize their long-term risk of thromboembolic disease. Hospitalists and outpatient providers often care for such patients who need to undergo a medical procedure or operation. The risk of bleeding associated with the medical procedure necessitates an interruption in the patient’s chronic oral anticoagulant therapy. In this scenario, providers are faced with several therapeutic decisions:

• How soon before the procedure should patients stop taking oral anticoagulant?
• During the period of time when the patient is not taking chronic oral anticoagulant, should the patient receive parenteral bridging anticoagulant therapy?
• After the procedure, when should patients restart chronic oral anticoagulant therapy?

‘Bridge’ anticoagulant therapy is the administration of a short-acting parenteral anticoagulant during the peri-operative period, when the patient is not taking chronic oral anticoagulant.¹ The intent of bridge anticoagulant therapy is to minimize both the risk of thromboembolic events and the risk of bleeding during the peri-operative period. Bridging anticoagulant therapy is appropriate for some but not all patients undergoing medical procedures.

The Data

When to discontinue warfarin? Warfarin, the most commonly prescribed oral anticoagulant, achieves its therapeutic effects by antagonizing the actions of endogenous vitamin K-dependent coagulation factors. The decision on when to stop warfarin prior to surgery is dependent on the regeneration time of coagulation factors following the discontinuation of warfarin therapy. Although warfarin’s half-life is typically 36-42 hours, its therapeutic effects typically last up to five days in healthy subjects and often longer in elderly patients.²

Current guidelines recommend the discontinuation of warfarin at least five days prior to surgery (Grade 1C recommendation).³ Despite this recommendation, approximately 7% of patients will still have an international normalized ratio (INR) >1.5 after not taking warfarin for five days.⁴ For this reason, the guidelines recommend that all patients have their INR checked on the day of surgery. For those patients with an INR of 1.5 to 1.9 on the day prior to surgery, there is evidence to show that administration of 1 mg of vitamin K will lower the INR to 1.4 in greater than 90% of cases.⁵

Assessment of peri-procedural thrombotic risk. Knowledge of a patient’s past medical history is critical in helping providers stratify the patient’s peri-procedural thrombotic risk. According to the 2012 American College of Chest Physicians (ACCP) guidelines, a history of atrial fibrillation (Afib), mechanical heart valve(s), and previous VTE are independent risk factors for peri-procedural thrombotic events.³ Hospitalists may risk-stratify their patients based on the anticipated annualized rate of thrombosis or embolization: <5%, 5%-10%, or >15% for the respective low, medium, and high-risk groups.⁶

Patients with Afib history. For these patients, the CHADS2 score helps to stratify the risk of peri-procedural thrombosis. Low risk is defined as a CHADS2 score of zero to two, assuming that the two points were not scored for transient ischemic attack (TIA) or cerebrovascular accident (CVA). Any patient with a TIA or CVA within the previous three months is automatically considered high risk. Medium risk is a score of three or four.

In addition to the aforementioned TIA or CVA within the prior three months, high-risk patients also include those with a CHADS2 score of five or six or any patient with a history of rheumatic heart disease.³ Patients with CHADS2 scores less than five but with a TIA or CVA greater than three months in the past are high risk.⁷

Presence of mechanical heart valve(s). For patients with a mechanical heart valve, knowledge of the valve type and location is essential to assist hospitalists in stratifying the risk of peri-procedural thrombosis. The current ACCP guidelines consider patients with bileaflet aortic valve prostheses without additional risk factors for stroke or atrial fibrillation to be low risk.³

The guidelines define the following characteristics as medium risk for patients: the presence of a bileaflet valve with additional risk factors for stroke such as atrial fibrillation, age greater than 75, prior CVA (more than six months prior), hypertension, diabetes mellitus, or congestive heart failure.

Patients at high risk include those with aortic valve prosthesis with a caged-ball or tilting disc, patients with mitral valve prosthesis, and those with a mechanical valve with CVA or TIA during the prior six months.⁷

History of previous VTE. For these patients, the duration of time that has passed since their last VTE event is an important factor in helping to stratify their risk for peri-procedural thrombosis. Hospitalists should consider patients low risk if they had VTE more than one year prior to the procedure.

Medium-risk patients are those with VTE events in the preceding three to twelve months, those with recurrent VTE, those with active cancer who have received cancer therapy within six months, or patients with non-severe thrombophilias (e.g. heterogenous factor V Leiden or prothrombin gene mutation).

Hospitalists should identify high-risk patients as those with VTE that has occurred within three months or those with severe thrombophilias such as Protein C or S deficiency, antithrombin III deficiency, or antiphospholipid antibody syndrome.

Assessment of procedure-related thrombotic risk. The type of anticipated procedure itself conveys peri-procedural thrombotic risk. For example, heart valve replacement, carotid endarterectomy, or other major vascular surgeries automatically stratify patients in the high-risk category, regardless of underlying medication condition.

Assessment of bleeding risk. Hospitalists must identify any preexisting bleeding risk factors (i.e., hemophilias or thrombocytopenia) in addition to the post-procedural bleeding risks. Risk factors for increased post-procedural bleeding include: major surgery with extensive tissue injury, procedures involving highly vascularized organs, removal of large colonic polyps, urological procedures, placement of implantable cardioverter-defibrillator/pacemakers, and procedures at sites where minor bleeding would be clinically devastating, such as the brain or spine.³

Thus, communication with the proceduralist or surgeon regarding the anticipated bleeding risk is vital.

Should the patient receive bridging anticoagulation? Patients considered high risk for peri-procedural thrombosis should receive peri-procedural bridging anticoagulation therapy, while those considered low risk should not. For patients with a moderate peri-procedural risk of thrombosis, hospitalists should base the decision on individual and anticipated pre-surgical/procedural thrombotic risks.

Recent evidence suggests that bridging anticoagulation should be avoided in patients undergoing procedures with high bleeding risk who are not at high thromboembolic risk.⁸

Selection and pre-operative discontinuation of bridging medication. Current ACCP guidelines only support the use of unfractionated heparin (UFH) or low molecular weight heparin (LMWH) as bridging anticoagulants.³ Evidence supports the use of either intravenous UFH (goal aPTT 1.5 to two times control aPTT) or enoxaparin (1 mg/kg BID or 1.5 mg/kg once daily).⁹ UFH is preferred over LMWH in patients with chronic kidney disease stage IV or V due to a more predictable pharmacokinetic profile.

Clinicians should initiate a bridge when a patient’s INR falls to less than 2.0 and discontinue the UFH bridge four to six hours prior to the procedure.¹⁰ The recent update to the guidelines now states that LMWH should be discontinued 24, instead of 12, hours prior to the procedure.³

When to restart UHF or LMWH bridge post-procedure. The type of procedure being performed dictates when bridging anticoagulation should resume. In patients who have undergone surgeries that involve high bleeding risk, LMWH should not be administered until 48-72 hours post-surgery (Grade 2C evidence).³ For those patients undergoing surgeries with low bleeding risk, bridging should be resumed approximately 24 hours after the procedure.

Of note, enoxaparin administered in one single daily dose, as compared to divided doses, is associated with a greater risk of post-operative bleeding. UFH bridging should resume post-operatively without a bolus dose at 24 hours in low-risk bleeding cases or 48-72 hours in high-risk bleeding cases (Grade 2C evidence).³

On occasion, unanticipated adjustments to surgical cases—or complications—change the previously determined post-operative bleeding risk. In these instances, the hospitalist and surgeon/proceduralist should review the case and reassess the bleeding risk prior to employing bridging anticoagulation protocols.

When to restart long-term vitamin K antagonists (VKA) post-procedure. In most instances, regardless of pre-operative bleeding risk stratification, the resumption of VKA may occur once post-operative hemostasis has been achieved and the patient has been instructed to resume eating by the proceduralist or surgeon. This most often occurs on the calendar day following surgery, because it takes approximately five days for an INR to achieve therapeutic levels.

Back to the Case

The patient’s history of prosthetic valve with stroke within the preceding six months stratified her to a high thrombotic risk category. Given the high risk of thrombosis, the decision was made to bridge with LMWH. The hospitalist discontinued LMWH 24 hours prior to surgery, and INR was checked on the morning of the procedure.

Although the patient underwent the operation without significant bleeding, the adjustment from an exploratory laparoscopy to an open laparotomy increased her post-operative bleeding risk from medium to high. Therefore, bridging anticoagulation with LMWH was resumed no sooner than 48 hours after the operation. Her warfarin was restarted on the day following surgery, once she resumed her diet.

Bottom Line

Hospitalists must understand both the pre- and post-procedure thrombotic risks, as well as the pre- and post-procedural bleeding risks, when determining the selection and logistics of initiation and cessation of antithrombotic bridging for inpatients.

Drs. McCormick, Carbo, and Li are hospitalists at Beth Israel Deaconess Medical Center in Boston. Dr. Kerbel is a hospitalist at the University of California Los Angeles.

References

1. BRIDGE Study Investigators. Bridging anticoagulation: is it needed when warfarin is interrupted around the time of a surgery or procedure? Circulation. 2012;125(12):e496-498.
2. Ansell J, Hirsh J, Hylek E, Jacobson A, Crowther M, Palareti G. Pharmacology and management of the vitamin K antagonists: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition). Chest. 2008;133(6 Suppl):160S-198S.
3. Douketis JD, Spyropoulos AC, Spencer FA, et al. Perioperative management of antithrombotic therapy: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines. Chest. 2012;141(2 Suppl):e326S-350S.
4. Kovacs MJ, Kearon C, Rodger M, et al. Single-arm study of bridging therapy with low-molecular-weight heparin for patients at risk of arterial embolism who require temporary interruption of warfarin. Circulation. 2004;110(12):1658-1663.
5. Woods K, Douketis JD, Kathirgamanathan K, Yi Q, Crowther MA. Low-dose oral vitamin K to normalize the international normalized ratio prior to surgery in patients who require temporary interruption of warfarin. J Thromb Thrombolysis. 2007;24(2):93-97.
6. Ortel TL. Perioperative management of patients on chronic antithrombotic therapy. Blood. 2012;120(24):4699-4705.
7. Kaatz S, Douketis JD, Zhou H, Gage BF, White RH. Risk of stroke after surgery in patients with and without chronic atrial fibrillation. J Thromb Haemost. 2010;8(5):884-890.
8. Siegal D, Yudin J, Kaatz S, Douketis JD, Lim W, Spyropoulos AC. Periprocedural heparin bridging in patients receiving vitamin K antagonists: systematic review and meta-analysis of bleeding and thromboembolic rates. Circulation. 2012;126(13):1630-1639.
9. Lee AY, Levine MN, Baker RI, et al. Low-molecular-weight heparin versus a coumarin for the prevention of recurrent venous thromboembolism in patients with cancer. N Engl J Med. 2003;349(2):146-153.
10. Hirsh J, Raschke R. Heparin and low-molecular-weight heparin: the Seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy. Chest. 2004;126(3 Suppl):188S-203S.

Weijen Chang, MD, SFHM, FAAP

Clinical question: Are clinical outcomes for dexamethasone equivalent to currently recommended corticosteroids for the treatment of children with mild to moderate asthma exacerbations?

Background: National and international guidelines uniformly agree that administration of a systemic corticosteroid is appropriate for children hospitalized with mild to moderate asthma exacerbations. Based on available literature, a 2007 update to an expert panel report developed by the National Asthma Education and Prevention Program recommended prednisone, methylprednisolone, or prednisolone at 1-2 mg/kg daily in two divided doses (maximum 60 mg/day).

Recent small studies have begun to examine the use of dexamethasone in acute asthma exacerbations. The longer half-life of dexamethasone enables shorter treatment regimens, which can improve compliance. Additionally, its taste is considered superior compared to currently recommended corticosteroids.

Study designs: Two meta-analyses of randomized controlled trials (RCT).

Setting: Six RCTs published between 1997 and 2008.

Synopsis: Both groups searched Medline for RCTs using the search terms “dexamethasone” and “asthma”; additional search terms included “decadron” and “status asthmaticus.” Limiting the search to a pediatric population was achieved by either using appropriate medical subject heading terms or by using an age limiter of ≤18 years of age.

Both groups performed meta-analyses of clinical outcomes, including rates of revisit to a healthcare provider and symptomatic improvement. Adverse effects, specifically vomiting, also underwent meta-analysis by both groups.

Interestingly, both groups analyzed the same six studies, and all six studies were in the ED setting. The dexamethasone regimens in the analyzed studies included single-dose intramuscular (0.3-1.7 mg/kg), single-dose oral (0.6 mg/kg), or two-dose (0.6 mg/kg/day given once daily) oral regimens. These were compared to three- or five-day regimens of prednisone or prednisolone. Not surprisingly, both groups reached similar conclusions.

Regarding symptomatic improvement and revisit rates, there was no significant difference between dexamethasone and prednisone/prednisolone groups. Vomiting was less likely in the dexamethasone groups overall.

Bottom line: Meta-analyses of small RCTs examining dexamethasone in the treatment of acute asthma exacerbations show that it is equivalent to prednisone/prednisolone in symptomatic improvement and risk of revisit, and possibly superior with regard to the risk of vomiting.

Citations: Meyer JS, Riese J, Biondi E. Is dexamethasone an effective alternative to oral prednisone in the treatment of pediatric asthma exacerbations? Hosp Pediatr. 2014;4(3):172-180. Keeney GE, Gray MP, Morrison AK. Dexamethasone for acute asthma exacerbations in children: a meta-analysis. Pediatrics. 2014;133(3):493-499.

Reviewed by Pediatric Editor Weijen Chang, MD, SFHM, FAAP, associate clinical professor of medicine and pediatrics at the University of California at San Diego School of Medicine, and a hospitalist at both UCSD Medical Center and Rady Children’s Hospital.

Weijen Chang, MD, SFHM, FAAP

Clinical question: Are clinical outcomes for dexamethasone equivalent to currently recommended corticosteroids for the treatment of children with mild to moderate asthma exacerbations?

Background: National and international guidelines uniformly agree that administration of a systemic corticosteroid is appropriate for children hospitalized with mild to moderate asthma exacerbations. Based on available literature, a 2007 update to an expert panel report developed by the National Asthma Education and Prevention Program recommended prednisone, methylprednisolone, or prednisolone at 1-2 mg/kg daily in two divided doses (maximum 60 mg/day).

Recent small studies have begun to examine the use of dexamethasone in acute asthma exacerbations. The longer half-life of dexamethasone enables shorter treatment regimens, which can improve compliance. Additionally, its taste is considered superior compared to currently recommended corticosteroids.

Study designs: Two meta-analyses of randomized controlled trials (RCT).

Setting: Six RCTs published between 1997 and 2008.

Synopsis: Both groups searched Medline for RCTs using the search terms “dexamethasone” and “asthma”; additional search terms included “decadron” and “status asthmaticus.” Limiting the search to a pediatric population was achieved by either using appropriate medical subject heading terms or by using an age limiter of ≤18 years of age.

Both groups performed meta-analyses of clinical outcomes, including rates of revisit to a healthcare provider and symptomatic improvement. Adverse effects, specifically vomiting, also underwent meta-analysis by both groups.

Interestingly, both groups analyzed the same six studies, and all six studies were in the ED setting. The dexamethasone regimens in the analyzed studies included single-dose intramuscular (0.3-1.7 mg/kg), single-dose oral (0.6 mg/kg), or two-dose (0.6 mg/kg/day given once daily) oral regimens. These were compared to three- or five-day regimens of prednisone or prednisolone. Not surprisingly, both groups reached similar conclusions.

Regarding symptomatic improvement and revisit rates, there was no significant difference between dexamethasone and prednisone/prednisolone groups. Vomiting was less likely in the dexamethasone groups overall.

Bottom line: Meta-analyses of small RCTs examining dexamethasone in the treatment of acute asthma exacerbations show that it is equivalent to prednisone/prednisolone in symptomatic improvement and risk of revisit, and possibly superior with regard to the risk of vomiting.

Citations: Meyer JS, Riese J, Biondi E. Is dexamethasone an effective alternative to oral prednisone in the treatment of pediatric asthma exacerbations? Hosp Pediatr. 2014;4(3):172-180. Keeney GE, Gray MP, Morrison AK. Dexamethasone for acute asthma exacerbations in children: a meta-analysis. Pediatrics. 2014;133(3):493-499.

Reviewed by Pediatric Editor Weijen Chang, MD, SFHM, FAAP, associate clinical professor of medicine and pediatrics at the University of California at San Diego School of Medicine, and a hospitalist at both UCSD Medical Center and Rady Children’s Hospital.

Weijen Chang, MD, SFHM, FAAP

Clinical question: Are clinical outcomes for dexamethasone equivalent to currently recommended corticosteroids for the treatment of children with mild to moderate asthma exacerbations?

Background: National and international guidelines uniformly agree that administration of a systemic corticosteroid is appropriate for children hospitalized with mild to moderate asthma exacerbations. Based on available literature, a 2007 update to an expert panel report developed by the National Asthma Education and Prevention Program recommended prednisone, methylprednisolone, or prednisolone at 1-2 mg/kg daily in two divided doses (maximum 60 mg/day).

Recent small studies have begun to examine the use of dexamethasone in acute asthma exacerbations. The longer half-life of dexamethasone enables shorter treatment regimens, which can improve compliance. Additionally, its taste is considered superior compared to currently recommended corticosteroids.

Study designs: Two meta-analyses of randomized controlled trials (RCT).

Setting: Six RCTs published between 1997 and 2008.

Synopsis: Both groups searched Medline for RCTs using the search terms “dexamethasone” and “asthma”; additional search terms included “decadron” and “status asthmaticus.” Limiting the search to a pediatric population was achieved by either using appropriate medical subject heading terms or by using an age limiter of ≤18 years of age.

Both groups performed meta-analyses of clinical outcomes, including rates of revisit to a healthcare provider and symptomatic improvement. Adverse effects, specifically vomiting, also underwent meta-analysis by both groups.

Interestingly, both groups analyzed the same six studies, and all six studies were in the ED setting. The dexamethasone regimens in the analyzed studies included single-dose intramuscular (0.3-1.7 mg/kg), single-dose oral (0.6 mg/kg), or two-dose (0.6 mg/kg/day given once daily) oral regimens. These were compared to three- or five-day regimens of prednisone or prednisolone. Not surprisingly, both groups reached similar conclusions.

Regarding symptomatic improvement and revisit rates, there was no significant difference between dexamethasone and prednisone/prednisolone groups. Vomiting was less likely in the dexamethasone groups overall.

Bottom line: Meta-analyses of small RCTs examining dexamethasone in the treatment of acute asthma exacerbations show that it is equivalent to prednisone/prednisolone in symptomatic improvement and risk of revisit, and possibly superior with regard to the risk of vomiting.

Citations: Meyer JS, Riese J, Biondi E. Is dexamethasone an effective alternative to oral prednisone in the treatment of pediatric asthma exacerbations? Hosp Pediatr. 2014;4(3):172-180. Keeney GE, Gray MP, Morrison AK. Dexamethasone for acute asthma exacerbations in children: a meta-analysis. Pediatrics. 2014;133(3):493-499.

Reviewed by Pediatric Editor Weijen Chang, MD, SFHM, FAAP, associate clinical professor of medicine and pediatrics at the University of California at San Diego School of Medicine, and a hospitalist at both UCSD Medical Center and Rady Children’s Hospital.

Clinical question: Does targeting a higher mean arterial pressure (MAP) in patients with septic shock lead to decreased mortality compared with targeting a more typical MAP range?

Background: The ideal blood pressure target for patients with septic shock is not currently known. There is some clinical evidence that patients with chronic arterial hypertension may require higher blood pressure to sustain kidney function.

Study design: Multicenter, randomized, stratified, open-label clinical trial.

Setting: ICUs at 29 centers in France

Synopsis: Researchers randomized 776 patients with septic shock to receive vasopressor treatment to maintain a MAP of 80-85 mmHg (high-target group) or 65-70 mmHg (low-target group). There was no significant difference between groups in the primary outcome of death at 28 days (HR in the high target group 1.07; 95% CI 0.84-1.38; P=0.57).

In patients with chronic arterial hypertension, those who were randomized to the high-target group had a reduced risk of doubling of plasma creatinine or need for renal-replacement therapy from days one to seven. Patients in the high-target group received larger amounts of vasopressors and for a longer period of time. There was no difference between the groups in the overall incidence of serious adverse events, though significantly more patients in the high-target group (6.7%) developed new onset atrial fibrillation compared with those in the low-target group (2.8%).

Bottom line: Mortality at 28 days was not significantly different in patients with septic shock who were randomized to a higher MAP target compared to patients who had a lower MAP target; this lower target encompasses the 65 mmHg target that is listed in the Surviving Sepsis Campaign guidelines.

Citation: Asfar P, Meziani F, Hamel JF, et al. High versus low blood-pressure target in patients with septic shock. N Engl J Med. 2014;370(17):1583-1593.

Clinical question: Does targeting a higher mean arterial pressure (MAP) in patients with septic shock lead to decreased mortality compared with targeting a more typical MAP range?

Background: The ideal blood pressure target for patients with septic shock is not currently known. There is some clinical evidence that patients with chronic arterial hypertension may require higher blood pressure to sustain kidney function.

Study design: Multicenter, randomized, stratified, open-label clinical trial.

Setting: ICUs at 29 centers in France

Synopsis: Researchers randomized 776 patients with septic shock to receive vasopressor treatment to maintain a MAP of 80-85 mmHg (high-target group) or 65-70 mmHg (low-target group). There was no significant difference between groups in the primary outcome of death at 28 days (HR in the high target group 1.07; 95% CI 0.84-1.38; P=0.57).

In patients with chronic arterial hypertension, those who were randomized to the high-target group had a reduced risk of doubling of plasma creatinine or need for renal-replacement therapy from days one to seven. Patients in the high-target group received larger amounts of vasopressors and for a longer period of time. There was no difference between the groups in the overall incidence of serious adverse events, though significantly more patients in the high-target group (6.7%) developed new onset atrial fibrillation compared with those in the low-target group (2.8%).

Bottom line: Mortality at 28 days was not significantly different in patients with septic shock who were randomized to a higher MAP target compared to patients who had a lower MAP target; this lower target encompasses the 65 mmHg target that is listed in the Surviving Sepsis Campaign guidelines.

Citation: Asfar P, Meziani F, Hamel JF, et al. High versus low blood-pressure target in patients with septic shock. N Engl J Med. 2014;370(17):1583-1593.

Clinical question: Does targeting a higher mean arterial pressure (MAP) in patients with septic shock lead to decreased mortality compared with targeting a more typical MAP range?

Background: The ideal blood pressure target for patients with septic shock is not currently known. There is some clinical evidence that patients with chronic arterial hypertension may require higher blood pressure to sustain kidney function.

Study design: Multicenter, randomized, stratified, open-label clinical trial.

Setting: ICUs at 29 centers in France

Synopsis: Researchers randomized 776 patients with septic shock to receive vasopressor treatment to maintain a MAP of 80-85 mmHg (high-target group) or 65-70 mmHg (low-target group). There was no significant difference between groups in the primary outcome of death at 28 days (HR in the high target group 1.07; 95% CI 0.84-1.38; P=0.57).

In patients with chronic arterial hypertension, those who were randomized to the high-target group had a reduced risk of doubling of plasma creatinine or need for renal-replacement therapy from days one to seven. Patients in the high-target group received larger amounts of vasopressors and for a longer period of time. There was no difference between the groups in the overall incidence of serious adverse events, though significantly more patients in the high-target group (6.7%) developed new onset atrial fibrillation compared with those in the low-target group (2.8%).

Bottom line: Mortality at 28 days was not significantly different in patients with septic shock who were randomized to a higher MAP target compared to patients who had a lower MAP target; this lower target encompasses the 65 mmHg target that is listed in the Surviving Sepsis Campaign guidelines.

Citation: Asfar P, Meziani F, Hamel JF, et al. High versus low blood-pressure target in patients with septic shock. N Engl J Med. 2014;370(17):1583-1593.

Clinical question: Do different thresholds for red blood cell (RBC) transfusion influence the risk of infection, and does leukocyte reduction also influence the risk of infection?

Background: RBC transfusion is a common and costly medical intervention performed across U.S. hospitals. Scientists suspect that RBC transfusion may have immunomodulatory properties and may affect a patient’s risk of acquiring various infections.

Study design: Meta-analysis and systematic review.

Setting: International adult, pediatric, obstetric medical and surgical wards, and ICUs.

Synopsis: Eighteen studies performed were included in the meta-analysis of published randomized trials comparing restrictive to liberal RBC transfusion strategies in which infectious outcomes were reported. Patient enrollment spanned from 1994 to 2012. Six of the trials included pediatric patients. For adult patients, the restrictive RBC transfusion threshold ranged from 6.4–9.7 g/dL, while the liberal target ranged from 9-11.3 g/dL in included trials.

The overall pooled risk ratio for the association of restrictive vs. liberal transfusion threshold with infection was 0.99 (95% CI, 0.78-0.99; P=0.033). A decreased risk of infection with the use of a restrictive transfusion compared with a liberal threshold persisted in studies of leukocyte-reduced blood products.

Bottom line: Restrictive RBC transfusion thresholds are associated with a decreased risk of acquiring healthcare-associated infections compared with liberal transfusion thresholds.

Citation: Rohde JM, Dimcheff DE, Blumberg N, et al. Health care-associated infection after red blood cell transfusion: A systematic review and meta-analysis. JAMA. 2014;311(13):1317-1326.

Clinical question: Do different thresholds for red blood cell (RBC) transfusion influence the risk of infection, and does leukocyte reduction also influence the risk of infection?

Background: RBC transfusion is a common and costly medical intervention performed across U.S. hospitals. Scientists suspect that RBC transfusion may have immunomodulatory properties and may affect a patient’s risk of acquiring various infections.

Study design: Meta-analysis and systematic review.

Setting: International adult, pediatric, obstetric medical and surgical wards, and ICUs.

Synopsis: Eighteen studies performed were included in the meta-analysis of published randomized trials comparing restrictive to liberal RBC transfusion strategies in which infectious outcomes were reported. Patient enrollment spanned from 1994 to 2012. Six of the trials included pediatric patients. For adult patients, the restrictive RBC transfusion threshold ranged from 6.4–9.7 g/dL, while the liberal target ranged from 9-11.3 g/dL in included trials.

The overall pooled risk ratio for the association of restrictive vs. liberal transfusion threshold with infection was 0.99 (95% CI, 0.78-0.99; P=0.033). A decreased risk of infection with the use of a restrictive transfusion compared with a liberal threshold persisted in studies of leukocyte-reduced blood products.

Bottom line: Restrictive RBC transfusion thresholds are associated with a decreased risk of acquiring healthcare-associated infections compared with liberal transfusion thresholds.

Citation: Rohde JM, Dimcheff DE, Blumberg N, et al. Health care-associated infection after red blood cell transfusion: A systematic review and meta-analysis. JAMA. 2014;311(13):1317-1326.

Clinical question: Do different thresholds for red blood cell (RBC) transfusion influence the risk of infection, and does leukocyte reduction also influence the risk of infection?

Background: RBC transfusion is a common and costly medical intervention performed across U.S. hospitals. Scientists suspect that RBC transfusion may have immunomodulatory properties and may affect a patient’s risk of acquiring various infections.

Study design: Meta-analysis and systematic review.

Setting: International adult, pediatric, obstetric medical and surgical wards, and ICUs.

Synopsis: Eighteen studies performed were included in the meta-analysis of published randomized trials comparing restrictive to liberal RBC transfusion strategies in which infectious outcomes were reported. Patient enrollment spanned from 1994 to 2012. Six of the trials included pediatric patients. For adult patients, the restrictive RBC transfusion threshold ranged from 6.4–9.7 g/dL, while the liberal target ranged from 9-11.3 g/dL in included trials.

The overall pooled risk ratio for the association of restrictive vs. liberal transfusion threshold with infection was 0.99 (95% CI, 0.78-0.99; P=0.033). A decreased risk of infection with the use of a restrictive transfusion compared with a liberal threshold persisted in studies of leukocyte-reduced blood products.

Bottom line: Restrictive RBC transfusion thresholds are associated with a decreased risk of acquiring healthcare-associated infections compared with liberal transfusion thresholds.

Citation: Rohde JM, Dimcheff DE, Blumberg N, et al. Health care-associated infection after red blood cell transfusion: A systematic review and meta-analysis. JAMA. 2014;311(13):1317-1326.

Clinical question: Are CT scans of the head diagnostically helpful in hospitalized patients with delirium?

Background: Studies have investigated the use of head CT scans for the evaluation of delirium in the ED, but there is scant information about the utility of head CT scans in the assessment of the hospitalized patient with delirium.

Study design: Retrospective medical record review.

Setting: Large academic medical center in Massachusetts.

Synopsis: This study was designed to assess whether head CT scans obtained on patients without a history of head trauma, fall, known intracranial process, or new neurologic deficit were useful in the workup of delirium. During a two-year period, 1,714 CT scans of the head were performed, and 398 listed the indication for the scan as “delirium, altered mental status, confusion, encephalopathy, somnolence, or unresponsiveness.” Patients with the risk factors of trauma, fall, new neurologic deficit, and known intracranial process were excluded, and 220 patients’ records were reviewed.

Only six head CT scans (2.7%) revealed an acute intracranial process. Many chronic findings were noted, such as atrophy, small vessel ischemic disease, and old stroke. The authors found that the diagnostic utility was low for a head CT scan in a patient with delirium but noted no risk factors. There may be a subset of patients in whom the diagnostic yield is higher, such as those on anticoagulation or more obtunded patients.

Bottom line: In delirious inpatients without a history of head trauma, fall, known intracranial process, or new neurologic deficit, head CT scan has low diagnostic utility.

Citation: Theisen-Toupal J, Breu AC, Mattison ML, Arnaout R. Diagnostic yield of head computed tomography for the hospitalized medical patient with delirium [published online ahead of print April 15, 2014]. J Hosp Med.

Clinical question: Are CT scans of the head diagnostically helpful in hospitalized patients with delirium?

Background: Studies have investigated the use of head CT scans for the evaluation of delirium in the ED, but there is scant information about the utility of head CT scans in the assessment of the hospitalized patient with delirium.

Study design: Retrospective medical record review.

Setting: Large academic medical center in Massachusetts.

Synopsis: This study was designed to assess whether head CT scans obtained on patients without a history of head trauma, fall, known intracranial process, or new neurologic deficit were useful in the workup of delirium. During a two-year period, 1,714 CT scans of the head were performed, and 398 listed the indication for the scan as “delirium, altered mental status, confusion, encephalopathy, somnolence, or unresponsiveness.” Patients with the risk factors of trauma, fall, new neurologic deficit, and known intracranial process were excluded, and 220 patients’ records were reviewed.

Only six head CT scans (2.7%) revealed an acute intracranial process. Many chronic findings were noted, such as atrophy, small vessel ischemic disease, and old stroke. The authors found that the diagnostic utility was low for a head CT scan in a patient with delirium but noted no risk factors. There may be a subset of patients in whom the diagnostic yield is higher, such as those on anticoagulation or more obtunded patients.

Bottom line: In delirious inpatients without a history of head trauma, fall, known intracranial process, or new neurologic deficit, head CT scan has low diagnostic utility.

Citation: Theisen-Toupal J, Breu AC, Mattison ML, Arnaout R. Diagnostic yield of head computed tomography for the hospitalized medical patient with delirium [published online ahead of print April 15, 2014]. J Hosp Med.

Clinical question: Are CT scans of the head diagnostically helpful in hospitalized patients with delirium?

Background: Studies have investigated the use of head CT scans for the evaluation of delirium in the ED, but there is scant information about the utility of head CT scans in the assessment of the hospitalized patient with delirium.

Study design: Retrospective medical record review.

Setting: Large academic medical center in Massachusetts.

Synopsis: This study was designed to assess whether head CT scans obtained on patients without a history of head trauma, fall, known intracranial process, or new neurologic deficit were useful in the workup of delirium. During a two-year period, 1,714 CT scans of the head were performed, and 398 listed the indication for the scan as “delirium, altered mental status, confusion, encephalopathy, somnolence, or unresponsiveness.” Patients with the risk factors of trauma, fall, new neurologic deficit, and known intracranial process were excluded, and 220 patients’ records were reviewed.

Only six head CT scans (2.7%) revealed an acute intracranial process. Many chronic findings were noted, such as atrophy, small vessel ischemic disease, and old stroke. The authors found that the diagnostic utility was low for a head CT scan in a patient with delirium but noted no risk factors. There may be a subset of patients in whom the diagnostic yield is higher, such as those on anticoagulation or more obtunded patients.

Bottom line: In delirious inpatients without a history of head trauma, fall, known intracranial process, or new neurologic deficit, head CT scan has low diagnostic utility.

Citation: Theisen-Toupal J, Breu AC, Mattison ML, Arnaout R. Diagnostic yield of head computed tomography for the hospitalized medical patient with delirium [published online ahead of print April 15, 2014]. J Hosp Med.