Vascular

SCOTTSDALE, ARIZ. – “It’s surprising to me today, when I go proctor or watch a case, how people don’t understand the impact of radiation,” Dr. Mark A. Farber, professor of surgery and radiology at the University of North Carolina, Chapel Hill, said at the Southern Association for Vascular Surgery annual meeting. “Many times, I see people’s hands underneath and on the fluoroscopy machine.”

This flouting of the so-called ALARA principle (as low as reasonably achievable) happens in part because the number of complex procedures performed by vascular surgeons is increasing, despite what presenter Dr. Melissa Kirkwood, a vascular surgeon at the University of Texas Southwestern Medical Center, Dallas, told the audience is a lack of training in radiation dose terminology and basic safety principals.

Yet, practicing excellent radiation safety protocols is “paramount” according to Dr. Farber who, along with Dr. Kirkwood, shared insights on how to minimize dose to both patients and vascular specialists, whether it be from primary, leakage, or scatter radiation.

Table up, top down

Minimizing the air gap by as little as 100 mm – from 700 mm to 600 mm, for example – can reduce the dose of radiation from 17% to 29%, whereas a 10-cm increase in the air gap can result in as much as a 20%-38% increase in the radiation skin dose. This is essentially the application of the inverse square law, according to Dr. Kirkwood.

Although Dr. Farber said that some of the newer, more advanced machines have sensors that automatically detect where the collector should be in relation to the patient, he cautioned that, if your machine doesn’t have these “bells and whistles … remember that the skin dose decreases as the air gap decreases.”

Slow the frame rate

Another advantage to using new imaging systems, according to Dr. Farber, is that they allow the use of pulsed fluoroscopy for as few as 2 or 3 pulses/sec. The selected pulse rate determines the number of fluoroscopic image frames that are generated by the machine per second. This is significant when the dose savings are essential or for when performing simpler procedures, he said. “If you go from 7.5 frames down to 3 frames/sec, you can decrease the exposure for both you and your patient.”

Use between 15 and 30 pulses/sec for critical procedures where precision is crucial, but reducing the rate to 7.5 pulses/sec may result is as much as 70% less of a skin dose.

Add barriers

Don’t just assume that the lead shielding is doing the job. “It’s important that you keep up on this and have it tested regularly,” said Dr. Farber, who recently discovered his thyroid shield was cracked and needed to be replaced.

Additionally, consider the lead shielding of your staff, which, even if it is not used as frequently as the physician’s, can suffer from improper handling. “They fold it or crinkle it up and drop it on the floor. This can lead to problems,” he said. And be sure to remember leaded glasses, lead drapes for the sides of the table, and leaded ceiling-mounted or standing shields.

For extra protection, Dr. Farber recommended the use of disposable protective drapes with cut-outs that allow access to the patient while helping to reduce the amount of scatter radiation exposure to the operator’s limbs. At a tally of anywhere from 1 to 10 mGy/hour, scatter radiation emanating from the patient is a particular risk to the operator’s legs from the knees down, said Dr. Kirkwood, “depending on how tall you are.”

Using the disposable drapes also can result in a 12-fold decrease in the amount of scatter on the eyes, a 25-fold decrease in thyroid exposure to scatter, and a 29-fold decrease in the hands being exposed.

“They can be cumbersome at times, I admit,” Dr. Farber said. “But there can be no substitute for using protective drapes.”

Leaded aprons also can help cut radiation transmission rates, even if they are not foolproof. Wearing two-piece leaded apron systems can help cut down the body strain from the weight of the aprons; however, Dr. Farber said that, at his institution, they now use a suspended body shield system operated by a boom so there is no physical stress on the clinician.

Because the weightless system also provides additional protection for the specialist’s head and limbs, Dr. Farber said that the hefty price tag (approximately $50,000) is justified.

“The way I sold it to the hospital was I told them I could stop doing procedures, or they could get me one of these systems so I could do more procedures,” he said, adding he has had a weightless system installed on each side of the table. “They’ll get their money’s worth by the fact that you’re not over your exposure limit.”

And finally, don’t forget to protect the anesthesiologist! A standing shield that gives broad coverage area should suffice, Dr. Farber said.

Vary the technique

Altering the angle can help ensure that one area of the patient’s body isn’t being overexposed to radiation. Since previously irradiated skin reacts abnormally when re-exposed to radiation because the regeneration and repair of the dermis can take up to several weeks after the initial insult, the timing of the intervals between exposures is critical, said Dr. Kirkwood, adding that the Joint Commission recently recommended that all doses of fluoroscopically guided interventions performed within the past 6-12 months should be considered when assessing potential skin injury risk.

Change the collimation

Making it tighter, for example, can help improve image quality and reduce the radiation dose to both the patient and the operator, as can varying the acquisition rates.

Exit the room during DSA

During digital subtraction angiography, Dr. Farber said to “get away from the table if you can! It’s a huge dose you don’t need to be exposed to if you don’t need to be right next to the machine.” Dr. Kirkwood agreed: “Angiography is 10-100 times more dose than fluoroscopy.”

De-mag

Using a larger monitor allows the operator to see more detail without increasing the magnification, which also increases the dose in the amount of the diameter over the diameter squared. “By not magnifying up [from a field of view of 14 to 28] you will save yourself a factor of at least 4,” Dr. Farber said. “And the actual dose may be even less.”

Optimize imaging

Today’s advanced imaging systems mean that it’s easy to produce many high-quality images – CT scans and ultrasounds – that allow a deeper, more complete picture.

Having the number of images it is now possible to have on screen at once is “practice changing” because it can help clinicians see more possibilities for “how to do the case,” said Dr. Farber. “I’ve never heard anyone say, ’Well, I wish I didn’t have that extra imaging next to me.’ ”

Save images

But once you get it, don’t forget to keep it. “Many times you do an acquisition, you move the machine, and you realize you forget to save the image and now you’ve got to go back and do it all over again,” Dr. Farber lamented. But by once again making technology your friend, with functions that allow auto-return to previous positions, among other auto-commands, you can save the needed information and reduce any unnecessary dose exposure for both yourself and the patient, he said.

Protect your eyes

Cataracts are still all too common in the field, according to Dr. Farber. “It’s important that you have side shields on your glasses to cut down on the amount of radiation that comes in and around the glasses.” Eschew glasses that don’t overtly hug your face, he said.

Know your geometry

Don’t forget that, if you’re standing on the side of the imaging source, the scattering effect will be greater than if you’re on the side of the image receptor. Once again, an understanding of the inverse square law can be protective, according to Dr. Kirkwood: “As x-rays exit the source, there is an exponential decrease in the number of x-rays per unit area as the distance from the source increases.”

“It’s simple stuff,” concluded Dr. Farber. “If you get in the habit of doing these things you will cut down your radiation exposure.”

Neither Dr. Farber nor Dr. Kirkwood had any relevant disclosures.

[email protected]

On Twitter @whitneymcknight

SCOTTSDALE, ARIZ. – “It’s surprising to me today, when I go proctor or watch a case, how people don’t understand the impact of radiation,” Dr. Mark A. Farber, professor of surgery and radiology at the University of North Carolina, Chapel Hill, said at the Southern Association for Vascular Surgery annual meeting. “Many times, I see people’s hands underneath and on the fluoroscopy machine.”

This flouting of the so-called ALARA principle (as low as reasonably achievable) happens in part because the number of complex procedures performed by vascular surgeons is increasing, despite what presenter Dr. Melissa Kirkwood, a vascular surgeon at the University of Texas Southwestern Medical Center, Dallas, told the audience is a lack of training in radiation dose terminology and basic safety principals.

Yet, practicing excellent radiation safety protocols is “paramount” according to Dr. Farber who, along with Dr. Kirkwood, shared insights on how to minimize dose to both patients and vascular specialists, whether it be from primary, leakage, or scatter radiation.

Table up, top down

Minimizing the air gap by as little as 100 mm – from 700 mm to 600 mm, for example – can reduce the dose of radiation from 17% to 29%, whereas a 10-cm increase in the air gap can result in as much as a 20%-38% increase in the radiation skin dose. This is essentially the application of the inverse square law, according to Dr. Kirkwood.

Although Dr. Farber said that some of the newer, more advanced machines have sensors that automatically detect where the collector should be in relation to the patient, he cautioned that, if your machine doesn’t have these “bells and whistles … remember that the skin dose decreases as the air gap decreases.”

Slow the frame rate

Another advantage to using new imaging systems, according to Dr. Farber, is that they allow the use of pulsed fluoroscopy for as few as 2 or 3 pulses/sec. The selected pulse rate determines the number of fluoroscopic image frames that are generated by the machine per second. This is significant when the dose savings are essential or for when performing simpler procedures, he said. “If you go from 7.5 frames down to 3 frames/sec, you can decrease the exposure for both you and your patient.”

Use between 15 and 30 pulses/sec for critical procedures where precision is crucial, but reducing the rate to 7.5 pulses/sec may result is as much as 70% less of a skin dose.

Add barriers

Don’t just assume that the lead shielding is doing the job. “It’s important that you keep up on this and have it tested regularly,” said Dr. Farber, who recently discovered his thyroid shield was cracked and needed to be replaced.

Additionally, consider the lead shielding of your staff, which, even if it is not used as frequently as the physician’s, can suffer from improper handling. “They fold it or crinkle it up and drop it on the floor. This can lead to problems,” he said. And be sure to remember leaded glasses, lead drapes for the sides of the table, and leaded ceiling-mounted or standing shields.

For extra protection, Dr. Farber recommended the use of disposable protective drapes with cut-outs that allow access to the patient while helping to reduce the amount of scatter radiation exposure to the operator’s limbs. At a tally of anywhere from 1 to 10 mGy/hour, scatter radiation emanating from the patient is a particular risk to the operator’s legs from the knees down, said Dr. Kirkwood, “depending on how tall you are.”

Using the disposable drapes also can result in a 12-fold decrease in the amount of scatter on the eyes, a 25-fold decrease in thyroid exposure to scatter, and a 29-fold decrease in the hands being exposed.

“They can be cumbersome at times, I admit,” Dr. Farber said. “But there can be no substitute for using protective drapes.”

Leaded aprons also can help cut radiation transmission rates, even if they are not foolproof. Wearing two-piece leaded apron systems can help cut down the body strain from the weight of the aprons; however, Dr. Farber said that, at his institution, they now use a suspended body shield system operated by a boom so there is no physical stress on the clinician.

Because the weightless system also provides additional protection for the specialist’s head and limbs, Dr. Farber said that the hefty price tag (approximately $50,000) is justified.

“The way I sold it to the hospital was I told them I could stop doing procedures, or they could get me one of these systems so I could do more procedures,” he said, adding he has had a weightless system installed on each side of the table. “They’ll get their money’s worth by the fact that you’re not over your exposure limit.”

And finally, don’t forget to protect the anesthesiologist! A standing shield that gives broad coverage area should suffice, Dr. Farber said.

Vary the technique

Altering the angle can help ensure that one area of the patient’s body isn’t being overexposed to radiation. Since previously irradiated skin reacts abnormally when re-exposed to radiation because the regeneration and repair of the dermis can take up to several weeks after the initial insult, the timing of the intervals between exposures is critical, said Dr. Kirkwood, adding that the Joint Commission recently recommended that all doses of fluoroscopically guided interventions performed within the past 6-12 months should be considered when assessing potential skin injury risk.

Change the collimation

Making it tighter, for example, can help improve image quality and reduce the radiation dose to both the patient and the operator, as can varying the acquisition rates.

Exit the room during DSA

During digital subtraction angiography, Dr. Farber said to “get away from the table if you can! It’s a huge dose you don’t need to be exposed to if you don’t need to be right next to the machine.” Dr. Kirkwood agreed: “Angiography is 10-100 times more dose than fluoroscopy.”

De-mag

Using a larger monitor allows the operator to see more detail without increasing the magnification, which also increases the dose in the amount of the diameter over the diameter squared. “By not magnifying up [from a field of view of 14 to 28] you will save yourself a factor of at least 4,” Dr. Farber said. “And the actual dose may be even less.”

Optimize imaging

Today’s advanced imaging systems mean that it’s easy to produce many high-quality images – CT scans and ultrasounds – that allow a deeper, more complete picture.

Having the number of images it is now possible to have on screen at once is “practice changing” because it can help clinicians see more possibilities for “how to do the case,” said Dr. Farber. “I’ve never heard anyone say, ’Well, I wish I didn’t have that extra imaging next to me.’ ”

Save images

But once you get it, don’t forget to keep it. “Many times you do an acquisition, you move the machine, and you realize you forget to save the image and now you’ve got to go back and do it all over again,” Dr. Farber lamented. But by once again making technology your friend, with functions that allow auto-return to previous positions, among other auto-commands, you can save the needed information and reduce any unnecessary dose exposure for both yourself and the patient, he said.

Protect your eyes

Cataracts are still all too common in the field, according to Dr. Farber. “It’s important that you have side shields on your glasses to cut down on the amount of radiation that comes in and around the glasses.” Eschew glasses that don’t overtly hug your face, he said.

Know your geometry

Don’t forget that, if you’re standing on the side of the imaging source, the scattering effect will be greater than if you’re on the side of the image receptor. Once again, an understanding of the inverse square law can be protective, according to Dr. Kirkwood: “As x-rays exit the source, there is an exponential decrease in the number of x-rays per unit area as the distance from the source increases.”

“It’s simple stuff,” concluded Dr. Farber. “If you get in the habit of doing these things you will cut down your radiation exposure.”

Neither Dr. Farber nor Dr. Kirkwood had any relevant disclosures.

[email protected]

On Twitter @whitneymcknight

SCOTTSDALE, ARIZ. – “It’s surprising to me today, when I go proctor or watch a case, how people don’t understand the impact of radiation,” Dr. Mark A. Farber, professor of surgery and radiology at the University of North Carolina, Chapel Hill, said at the Southern Association for Vascular Surgery annual meeting. “Many times, I see people’s hands underneath and on the fluoroscopy machine.”

This flouting of the so-called ALARA principle (as low as reasonably achievable) happens in part because the number of complex procedures performed by vascular surgeons is increasing, despite what presenter Dr. Melissa Kirkwood, a vascular surgeon at the University of Texas Southwestern Medical Center, Dallas, told the audience is a lack of training in radiation dose terminology and basic safety principals.

Yet, practicing excellent radiation safety protocols is “paramount” according to Dr. Farber who, along with Dr. Kirkwood, shared insights on how to minimize dose to both patients and vascular specialists, whether it be from primary, leakage, or scatter radiation.

Table up, top down

Minimizing the air gap by as little as 100 mm – from 700 mm to 600 mm, for example – can reduce the dose of radiation from 17% to 29%, whereas a 10-cm increase in the air gap can result in as much as a 20%-38% increase in the radiation skin dose. This is essentially the application of the inverse square law, according to Dr. Kirkwood.

Although Dr. Farber said that some of the newer, more advanced machines have sensors that automatically detect where the collector should be in relation to the patient, he cautioned that, if your machine doesn’t have these “bells and whistles … remember that the skin dose decreases as the air gap decreases.”

Slow the frame rate

Another advantage to using new imaging systems, according to Dr. Farber, is that they allow the use of pulsed fluoroscopy for as few as 2 or 3 pulses/sec. The selected pulse rate determines the number of fluoroscopic image frames that are generated by the machine per second. This is significant when the dose savings are essential or for when performing simpler procedures, he said. “If you go from 7.5 frames down to 3 frames/sec, you can decrease the exposure for both you and your patient.”

Use between 15 and 30 pulses/sec for critical procedures where precision is crucial, but reducing the rate to 7.5 pulses/sec may result is as much as 70% less of a skin dose.

Add barriers

Don’t just assume that the lead shielding is doing the job. “It’s important that you keep up on this and have it tested regularly,” said Dr. Farber, who recently discovered his thyroid shield was cracked and needed to be replaced.

Additionally, consider the lead shielding of your staff, which, even if it is not used as frequently as the physician’s, can suffer from improper handling. “They fold it or crinkle it up and drop it on the floor. This can lead to problems,” he said. And be sure to remember leaded glasses, lead drapes for the sides of the table, and leaded ceiling-mounted or standing shields.

For extra protection, Dr. Farber recommended the use of disposable protective drapes with cut-outs that allow access to the patient while helping to reduce the amount of scatter radiation exposure to the operator’s limbs. At a tally of anywhere from 1 to 10 mGy/hour, scatter radiation emanating from the patient is a particular risk to the operator’s legs from the knees down, said Dr. Kirkwood, “depending on how tall you are.”

Using the disposable drapes also can result in a 12-fold decrease in the amount of scatter on the eyes, a 25-fold decrease in thyroid exposure to scatter, and a 29-fold decrease in the hands being exposed.

“They can be cumbersome at times, I admit,” Dr. Farber said. “But there can be no substitute for using protective drapes.”

Leaded aprons also can help cut radiation transmission rates, even if they are not foolproof. Wearing two-piece leaded apron systems can help cut down the body strain from the weight of the aprons; however, Dr. Farber said that, at his institution, they now use a suspended body shield system operated by a boom so there is no physical stress on the clinician.

Because the weightless system also provides additional protection for the specialist’s head and limbs, Dr. Farber said that the hefty price tag (approximately $50,000) is justified.

“The way I sold it to the hospital was I told them I could stop doing procedures, or they could get me one of these systems so I could do more procedures,” he said, adding he has had a weightless system installed on each side of the table. “They’ll get their money’s worth by the fact that you’re not over your exposure limit.”

And finally, don’t forget to protect the anesthesiologist! A standing shield that gives broad coverage area should suffice, Dr. Farber said.

Vary the technique

Altering the angle can help ensure that one area of the patient’s body isn’t being overexposed to radiation. Since previously irradiated skin reacts abnormally when re-exposed to radiation because the regeneration and repair of the dermis can take up to several weeks after the initial insult, the timing of the intervals between exposures is critical, said Dr. Kirkwood, adding that the Joint Commission recently recommended that all doses of fluoroscopically guided interventions performed within the past 6-12 months should be considered when assessing potential skin injury risk.

Change the collimation

Making it tighter, for example, can help improve image quality and reduce the radiation dose to both the patient and the operator, as can varying the acquisition rates.

Exit the room during DSA

During digital subtraction angiography, Dr. Farber said to “get away from the table if you can! It’s a huge dose you don’t need to be exposed to if you don’t need to be right next to the machine.” Dr. Kirkwood agreed: “Angiography is 10-100 times more dose than fluoroscopy.”

De-mag

Using a larger monitor allows the operator to see more detail without increasing the magnification, which also increases the dose in the amount of the diameter over the diameter squared. “By not magnifying up [from a field of view of 14 to 28] you will save yourself a factor of at least 4,” Dr. Farber said. “And the actual dose may be even less.”

Optimize imaging

Today’s advanced imaging systems mean that it’s easy to produce many high-quality images – CT scans and ultrasounds – that allow a deeper, more complete picture.

Having the number of images it is now possible to have on screen at once is “practice changing” because it can help clinicians see more possibilities for “how to do the case,” said Dr. Farber. “I’ve never heard anyone say, ’Well, I wish I didn’t have that extra imaging next to me.’ ”

Save images

But once you get it, don’t forget to keep it. “Many times you do an acquisition, you move the machine, and you realize you forget to save the image and now you’ve got to go back and do it all over again,” Dr. Farber lamented. But by once again making technology your friend, with functions that allow auto-return to previous positions, among other auto-commands, you can save the needed information and reduce any unnecessary dose exposure for both yourself and the patient, he said.

Protect your eyes

Cataracts are still all too common in the field, according to Dr. Farber. “It’s important that you have side shields on your glasses to cut down on the amount of radiation that comes in and around the glasses.” Eschew glasses that don’t overtly hug your face, he said.

Know your geometry

Don’t forget that, if you’re standing on the side of the imaging source, the scattering effect will be greater than if you’re on the side of the image receptor. Once again, an understanding of the inverse square law can be protective, according to Dr. Kirkwood: “As x-rays exit the source, there is an exponential decrease in the number of x-rays per unit area as the distance from the source increases.”

“It’s simple stuff,” concluded Dr. Farber. “If you get in the habit of doing these things you will cut down your radiation exposure.”

Neither Dr. Farber nor Dr. Kirkwood had any relevant disclosures.

[email protected]

On Twitter @whitneymcknight

CORONADO, CALIF. – Skin injury following fenestrated endovascular aortic stent grafting is less prevalent than expected, results from a single-center retrospective study showed.

“Radiation-induced skin injury is a serious potential complication of fluoroscopically guided interventions,” Dr. Melissa L. Kirkwood said at the annual meeting of the Western Vascular Society. “These injuries are associated with a threshold radiation dose, above which the severity of injury increases with increasing dose. Instances of these injuries are mostly limited to case reports of coronary interventions, TIPS procedures, and neuroembolizations.”

These radiation-induced skin lesions can be classified as prompt, early, mid-term, or late depending on when they present following the fluoroscopically guided intervention. “The National Cancer Institute has defined four grades of skin injury, with the most frequent being transient erythema, a prompt reaction within the first 24 hours occurring at skin doses as low as 2 Gy,” said Dr. Kirkwood of the division of vascular and endovascular surgery at the University of Texas Southwestern Medical Center, Dallas. “With increasing skin doses, more severe effects present themselves. Atrophy, ulceration, and necrosis are possibilities.”

She went on to note that fenestrated endovascular aneurysm repairs often require high doses of radiation, yet the prevalence of deterministic skin injury following these cases is unknown. In a recent study, Dr. Kirkwood and her associates retrospectively reviewed 61 complex fluoroscopically guided interventions that met substantial radiation dose level criteria (SRDL), which is defined by the National Council on Radiation and Protection Measurements as a reference air kerma (RAK) greater than or equal to 5 Gy (J. Vasc. Surg. 2014; 60[3]:742-8). “Despite mean peak skin doses as high as 6.5 Gy, ranging up to 18.5 Gy, we did not detect any skin injuries in this cohort,” Dr. Kirkwood said. “That study, however, was limited by its retrospective design. There was no postoperative protocol in place to ensure that a thorough skin exam was performed on each patient at every follow-up visit. Therefore, we hypothesized that a more thorough postoperative follow-up of patients would detect some skin injury following these cases.”

For the current study, she and her associates sought to examine the prevalence of deterministic effects after FEVAR as well as well as any patient characteristics that may predispose patients to skin injury.

In June 2013, the researchers implemented a new policy regarding the follow-up of FEVAR patients, which involved a full skin exam at postoperative week 2 and 4, and at 3 and 6 months, as well as questioning patients about any skin-related complaints. For the current study, they retrospectively reviewed all FEVARs over a 7-month period after the change in policy and highlighted all the cases that reached a RAK of 5 Gy or greater. The RAK was the dose metric used in this study. It is a measure of the radiation dose to air at the interventional reference point, which, on standard fluoroscopes, is 15 cm along the beam axis toward the focal spot from isocenter. Dr. Kirkwood characterized RAK as “the best real-time indicator of patient dose, because it roughly estimates the dose at the entry point on the patient’s skin.” Peak skin dose, a dose index, and simulated skin dose maps were calculated using customized software employing input data from fluoroscopic machine logs.

Of 317 cases performed, 22 met or exceeded a RAK of 5 Gy. Of these, 21 were FEVARs and one was an embolization. Most patients (91%) were male and their mean body mass index was 30 kg/m². Comorbidities and risk factors for skin injury included smoking, diabetes, and the concomitant applications of chemotherapeutic agents.

Dr. Kirkwood reported that the average RAK for all FEVARs was 8 Gy, with a range of 5-11 Gy. Slightly more than half of patients (52%) had multiple fluoroscopically guided interventions within 6 months of their SRDL event. The average RAK for this subset of patients was 10 Gy (range of 5 to 15).

The mean peak skin dose for all FEVARs was 5 Gy (a range of 2 to 10 Gy), and the dose index was 0.69. The average peak skin dose for the subset of patients with multiple procedures was 7 Gy (a range of 3 to 9 Gy).

In terms of the follow-up, all 21 FEVAR patients were examined at the 1- or 2-week mark, 81% were examined at 1 month, 52% were examined at 3 months, and 62% were examined at 6 months. No radiation skin injuries were reported. “Based on the published data, we would expect to see all grades of skin injury, especially in the cohort of the 5-10 Gy,” Dr. Kirkwood said.

In the previous study, conducted prior to the new follow-up policy, the dose index for FEVARs was 0.78, “meaning that the peak skin dose that the patient received could be roughly estimated as 78% of the RAK dose displayed on the monitor,” Dr. Kirkwood explained. “In the current work, the dose index decreased to 60%. This suggests that surgeons in our group have now more appropriately and effectively employed strategies to decrease radiation dose to the patient. However, even when the best operating practice is employed, FEVARs still continue to require high radiation doses in order to complete. “

The present study demonstrated that deterministic skin injuries “are uncommon after FEVAR, even at high RAK levels and regardless of cumulative dose,” she concluded. “Even with more comprehensive patient follow-up, the fact that no skin injuries were reported suggests that skin injuries in this patient cohort are less prevalent than the published guidelines would predict.”

Dr. Kirkwood reported having no financial disclosures.

[email protected]

On Twitter @dougbrunk

CORONADO, CALIF. – Skin injury following fenestrated endovascular aortic stent grafting is less prevalent than expected, results from a single-center retrospective study showed.

“Radiation-induced skin injury is a serious potential complication of fluoroscopically guided interventions,” Dr. Melissa L. Kirkwood said at the annual meeting of the Western Vascular Society. “These injuries are associated with a threshold radiation dose, above which the severity of injury increases with increasing dose. Instances of these injuries are mostly limited to case reports of coronary interventions, TIPS procedures, and neuroembolizations.”

These radiation-induced skin lesions can be classified as prompt, early, mid-term, or late depending on when they present following the fluoroscopically guided intervention. “The National Cancer Institute has defined four grades of skin injury, with the most frequent being transient erythema, a prompt reaction within the first 24 hours occurring at skin doses as low as 2 Gy,” said Dr. Kirkwood of the division of vascular and endovascular surgery at the University of Texas Southwestern Medical Center, Dallas. “With increasing skin doses, more severe effects present themselves. Atrophy, ulceration, and necrosis are possibilities.”

She went on to note that fenestrated endovascular aneurysm repairs often require high doses of radiation, yet the prevalence of deterministic skin injury following these cases is unknown. In a recent study, Dr. Kirkwood and her associates retrospectively reviewed 61 complex fluoroscopically guided interventions that met substantial radiation dose level criteria (SRDL), which is defined by the National Council on Radiation and Protection Measurements as a reference air kerma (RAK) greater than or equal to 5 Gy (J. Vasc. Surg. 2014; 60[3]:742-8). “Despite mean peak skin doses as high as 6.5 Gy, ranging up to 18.5 Gy, we did not detect any skin injuries in this cohort,” Dr. Kirkwood said. “That study, however, was limited by its retrospective design. There was no postoperative protocol in place to ensure that a thorough skin exam was performed on each patient at every follow-up visit. Therefore, we hypothesized that a more thorough postoperative follow-up of patients would detect some skin injury following these cases.”

For the current study, she and her associates sought to examine the prevalence of deterministic effects after FEVAR as well as well as any patient characteristics that may predispose patients to skin injury.

In June 2013, the researchers implemented a new policy regarding the follow-up of FEVAR patients, which involved a full skin exam at postoperative week 2 and 4, and at 3 and 6 months, as well as questioning patients about any skin-related complaints. For the current study, they retrospectively reviewed all FEVARs over a 7-month period after the change in policy and highlighted all the cases that reached a RAK of 5 Gy or greater. The RAK was the dose metric used in this study. It is a measure of the radiation dose to air at the interventional reference point, which, on standard fluoroscopes, is 15 cm along the beam axis toward the focal spot from isocenter. Dr. Kirkwood characterized RAK as “the best real-time indicator of patient dose, because it roughly estimates the dose at the entry point on the patient’s skin.” Peak skin dose, a dose index, and simulated skin dose maps were calculated using customized software employing input data from fluoroscopic machine logs.

Of 317 cases performed, 22 met or exceeded a RAK of 5 Gy. Of these, 21 were FEVARs and one was an embolization. Most patients (91%) were male and their mean body mass index was 30 kg/m². Comorbidities and risk factors for skin injury included smoking, diabetes, and the concomitant applications of chemotherapeutic agents.

Dr. Kirkwood reported that the average RAK for all FEVARs was 8 Gy, with a range of 5-11 Gy. Slightly more than half of patients (52%) had multiple fluoroscopically guided interventions within 6 months of their SRDL event. The average RAK for this subset of patients was 10 Gy (range of 5 to 15).

The mean peak skin dose for all FEVARs was 5 Gy (a range of 2 to 10 Gy), and the dose index was 0.69. The average peak skin dose for the subset of patients with multiple procedures was 7 Gy (a range of 3 to 9 Gy).

In terms of the follow-up, all 21 FEVAR patients were examined at the 1- or 2-week mark, 81% were examined at 1 month, 52% were examined at 3 months, and 62% were examined at 6 months. No radiation skin injuries were reported. “Based on the published data, we would expect to see all grades of skin injury, especially in the cohort of the 5-10 Gy,” Dr. Kirkwood said.

In the previous study, conducted prior to the new follow-up policy, the dose index for FEVARs was 0.78, “meaning that the peak skin dose that the patient received could be roughly estimated as 78% of the RAK dose displayed on the monitor,” Dr. Kirkwood explained. “In the current work, the dose index decreased to 60%. This suggests that surgeons in our group have now more appropriately and effectively employed strategies to decrease radiation dose to the patient. However, even when the best operating practice is employed, FEVARs still continue to require high radiation doses in order to complete. “

The present study demonstrated that deterministic skin injuries “are uncommon after FEVAR, even at high RAK levels and regardless of cumulative dose,” she concluded. “Even with more comprehensive patient follow-up, the fact that no skin injuries were reported suggests that skin injuries in this patient cohort are less prevalent than the published guidelines would predict.”

Dr. Kirkwood reported having no financial disclosures.

[email protected]

On Twitter @dougbrunk

CORONADO, CALIF. – Skin injury following fenestrated endovascular aortic stent grafting is less prevalent than expected, results from a single-center retrospective study showed.

“Radiation-induced skin injury is a serious potential complication of fluoroscopically guided interventions,” Dr. Melissa L. Kirkwood said at the annual meeting of the Western Vascular Society. “These injuries are associated with a threshold radiation dose, above which the severity of injury increases with increasing dose. Instances of these injuries are mostly limited to case reports of coronary interventions, TIPS procedures, and neuroembolizations.”

These radiation-induced skin lesions can be classified as prompt, early, mid-term, or late depending on when they present following the fluoroscopically guided intervention. “The National Cancer Institute has defined four grades of skin injury, with the most frequent being transient erythema, a prompt reaction within the first 24 hours occurring at skin doses as low as 2 Gy,” said Dr. Kirkwood of the division of vascular and endovascular surgery at the University of Texas Southwestern Medical Center, Dallas. “With increasing skin doses, more severe effects present themselves. Atrophy, ulceration, and necrosis are possibilities.”

She went on to note that fenestrated endovascular aneurysm repairs often require high doses of radiation, yet the prevalence of deterministic skin injury following these cases is unknown. In a recent study, Dr. Kirkwood and her associates retrospectively reviewed 61 complex fluoroscopically guided interventions that met substantial radiation dose level criteria (SRDL), which is defined by the National Council on Radiation and Protection Measurements as a reference air kerma (RAK) greater than or equal to 5 Gy (J. Vasc. Surg. 2014; 60[3]:742-8). “Despite mean peak skin doses as high as 6.5 Gy, ranging up to 18.5 Gy, we did not detect any skin injuries in this cohort,” Dr. Kirkwood said. “That study, however, was limited by its retrospective design. There was no postoperative protocol in place to ensure that a thorough skin exam was performed on each patient at every follow-up visit. Therefore, we hypothesized that a more thorough postoperative follow-up of patients would detect some skin injury following these cases.”

For the current study, she and her associates sought to examine the prevalence of deterministic effects after FEVAR as well as well as any patient characteristics that may predispose patients to skin injury.

In June 2013, the researchers implemented a new policy regarding the follow-up of FEVAR patients, which involved a full skin exam at postoperative week 2 and 4, and at 3 and 6 months, as well as questioning patients about any skin-related complaints. For the current study, they retrospectively reviewed all FEVARs over a 7-month period after the change in policy and highlighted all the cases that reached a RAK of 5 Gy or greater. The RAK was the dose metric used in this study. It is a measure of the radiation dose to air at the interventional reference point, which, on standard fluoroscopes, is 15 cm along the beam axis toward the focal spot from isocenter. Dr. Kirkwood characterized RAK as “the best real-time indicator of patient dose, because it roughly estimates the dose at the entry point on the patient’s skin.” Peak skin dose, a dose index, and simulated skin dose maps were calculated using customized software employing input data from fluoroscopic machine logs.

Of 317 cases performed, 22 met or exceeded a RAK of 5 Gy. Of these, 21 were FEVARs and one was an embolization. Most patients (91%) were male and their mean body mass index was 30 kg/m². Comorbidities and risk factors for skin injury included smoking, diabetes, and the concomitant applications of chemotherapeutic agents.

Dr. Kirkwood reported that the average RAK for all FEVARs was 8 Gy, with a range of 5-11 Gy. Slightly more than half of patients (52%) had multiple fluoroscopically guided interventions within 6 months of their SRDL event. The average RAK for this subset of patients was 10 Gy (range of 5 to 15).

The mean peak skin dose for all FEVARs was 5 Gy (a range of 2 to 10 Gy), and the dose index was 0.69. The average peak skin dose for the subset of patients with multiple procedures was 7 Gy (a range of 3 to 9 Gy).

In terms of the follow-up, all 21 FEVAR patients were examined at the 1- or 2-week mark, 81% were examined at 1 month, 52% were examined at 3 months, and 62% were examined at 6 months. No radiation skin injuries were reported. “Based on the published data, we would expect to see all grades of skin injury, especially in the cohort of the 5-10 Gy,” Dr. Kirkwood said.

In the previous study, conducted prior to the new follow-up policy, the dose index for FEVARs was 0.78, “meaning that the peak skin dose that the patient received could be roughly estimated as 78% of the RAK dose displayed on the monitor,” Dr. Kirkwood explained. “In the current work, the dose index decreased to 60%. This suggests that surgeons in our group have now more appropriately and effectively employed strategies to decrease radiation dose to the patient. However, even when the best operating practice is employed, FEVARs still continue to require high radiation doses in order to complete. “

The present study demonstrated that deterministic skin injuries “are uncommon after FEVAR, even at high RAK levels and regardless of cumulative dose,” she concluded. “Even with more comprehensive patient follow-up, the fact that no skin injuries were reported suggests that skin injuries in this patient cohort are less prevalent than the published guidelines would predict.”

Dr. Kirkwood reported having no financial disclosures.

[email protected]

On Twitter @dougbrunk

PHILADELPHIA – A covered nitinol stent graft effectively restored and maintained patency of hemodialysis access routes that had been impaired by in-stent restenosis.

The combination of a stent graft plus angioplasty was significantly more effective than angioplasty alone at keeping the access routes open, Dr. Alexander Yevzlin reported at Kidney Week 2014.

Maintaining healthy vascular access is key for effective dialysis; this is usually accomplished by bare metal stenting. However, in-stent restenosis is so common that patients may need angioplasty every 3-6 months to maintain access patency.

In comparison, coronary angioplasty is usually sustained for at least 5 years, said Dr. Yevzlin, director of interventional nephrology at the University of Wisconsin, Madison. “This places a very large extra burden of morbidity on patients, and a large burden of cost on society.”

The ongoing RESCUE study is examining the Fluency Plus cardiovascular stent graft for in-stent restenosis. Fluency is a nitinol stent covered with a plastic graft of expanded polytetrafluoroethylene. Dr. Yevzlin reported preliminary 6-month data.

The study has randomized 265 patients with in-stent restenosis of a dialysis access circuit to treatment with either balloon angioplasty alone, or angioplasty plus the stent graft. The primary endpoints are access circuit primary patency at 6 months and 30-day safety. Safety endpoints are any additional interventions including surgery, hospitalization, or prolongation of an existing hospitalization; or death. The secondary endpoint is postintervention lesion patency (defined as the interval after the index intervention until the next reintervention at the original treatment site or until the extremity is abandoned for permanent access).

There were no safety issues, Dr. Yevzlin said; by 30 days, 97% of patients in both groups were still free of any adverse event.

By 6 months, access circuit patency was significantly higher among those who received stent grafts than those who had angioplasties alone. Postintervention lesion patency was 65% in the stent graft group and 10% in the angioplasty group – a significant difference.

The stent graft performed well in both arteriovenous grafts and fistulas. In a subgroup of those with an arteriovenous graft, the postinterventional lesion patency rate was 58% in the stent graft group and 5% in the angioplasty group. In the fistula subgroup, the rates were 72% and 15%, respectively.

The meeting was sponsored by the American Society of Nephrology. Dr. Yevzlin disclosed financial relationships with Bard Peripheral Vascular, the manufacturer of the stent graft; Phraxis; CytoPherx; and Covidien.

[email protected]

PHILADELPHIA – A covered nitinol stent graft effectively restored and maintained patency of hemodialysis access routes that had been impaired by in-stent restenosis.

The combination of a stent graft plus angioplasty was significantly more effective than angioplasty alone at keeping the access routes open, Dr. Alexander Yevzlin reported at Kidney Week 2014.

Maintaining healthy vascular access is key for effective dialysis; this is usually accomplished by bare metal stenting. However, in-stent restenosis is so common that patients may need angioplasty every 3-6 months to maintain access patency.

In comparison, coronary angioplasty is usually sustained for at least 5 years, said Dr. Yevzlin, director of interventional nephrology at the University of Wisconsin, Madison. “This places a very large extra burden of morbidity on patients, and a large burden of cost on society.”

The ongoing RESCUE study is examining the Fluency Plus cardiovascular stent graft for in-stent restenosis. Fluency is a nitinol stent covered with a plastic graft of expanded polytetrafluoroethylene. Dr. Yevzlin reported preliminary 6-month data.

The study has randomized 265 patients with in-stent restenosis of a dialysis access circuit to treatment with either balloon angioplasty alone, or angioplasty plus the stent graft. The primary endpoints are access circuit primary patency at 6 months and 30-day safety. Safety endpoints are any additional interventions including surgery, hospitalization, or prolongation of an existing hospitalization; or death. The secondary endpoint is postintervention lesion patency (defined as the interval after the index intervention until the next reintervention at the original treatment site or until the extremity is abandoned for permanent access).

There were no safety issues, Dr. Yevzlin said; by 30 days, 97% of patients in both groups were still free of any adverse event.

By 6 months, access circuit patency was significantly higher among those who received stent grafts than those who had angioplasties alone. Postintervention lesion patency was 65% in the stent graft group and 10% in the angioplasty group – a significant difference.

The stent graft performed well in both arteriovenous grafts and fistulas. In a subgroup of those with an arteriovenous graft, the postinterventional lesion patency rate was 58% in the stent graft group and 5% in the angioplasty group. In the fistula subgroup, the rates were 72% and 15%, respectively.

The meeting was sponsored by the American Society of Nephrology. Dr. Yevzlin disclosed financial relationships with Bard Peripheral Vascular, the manufacturer of the stent graft; Phraxis; CytoPherx; and Covidien.

[email protected]

PHILADELPHIA – A covered nitinol stent graft effectively restored and maintained patency of hemodialysis access routes that had been impaired by in-stent restenosis.

The combination of a stent graft plus angioplasty was significantly more effective than angioplasty alone at keeping the access routes open, Dr. Alexander Yevzlin reported at Kidney Week 2014.

Maintaining healthy vascular access is key for effective dialysis; this is usually accomplished by bare metal stenting. However, in-stent restenosis is so common that patients may need angioplasty every 3-6 months to maintain access patency.

In comparison, coronary angioplasty is usually sustained for at least 5 years, said Dr. Yevzlin, director of interventional nephrology at the University of Wisconsin, Madison. “This places a very large extra burden of morbidity on patients, and a large burden of cost on society.”

The ongoing RESCUE study is examining the Fluency Plus cardiovascular stent graft for in-stent restenosis. Fluency is a nitinol stent covered with a plastic graft of expanded polytetrafluoroethylene. Dr. Yevzlin reported preliminary 6-month data.

The study has randomized 265 patients with in-stent restenosis of a dialysis access circuit to treatment with either balloon angioplasty alone, or angioplasty plus the stent graft. The primary endpoints are access circuit primary patency at 6 months and 30-day safety. Safety endpoints are any additional interventions including surgery, hospitalization, or prolongation of an existing hospitalization; or death. The secondary endpoint is postintervention lesion patency (defined as the interval after the index intervention until the next reintervention at the original treatment site or until the extremity is abandoned for permanent access).

There were no safety issues, Dr. Yevzlin said; by 30 days, 97% of patients in both groups were still free of any adverse event.

By 6 months, access circuit patency was significantly higher among those who received stent grafts than those who had angioplasties alone. Postintervention lesion patency was 65% in the stent graft group and 10% in the angioplasty group – a significant difference.

The stent graft performed well in both arteriovenous grafts and fistulas. In a subgroup of those with an arteriovenous graft, the postinterventional lesion patency rate was 58% in the stent graft group and 5% in the angioplasty group. In the fistula subgroup, the rates were 72% and 15%, respectively.

The meeting was sponsored by the American Society of Nephrology. Dr. Yevzlin disclosed financial relationships with Bard Peripheral Vascular, the manufacturer of the stent graft; Phraxis; CytoPherx; and Covidien.

[email protected]

CORONADO, CALIF. – Cranial nerve injury occurred in 4.6% of patients who participated in the Carotid Revascularization Endarterectomy versus Stenting Trial (CREST), with 34% resolution at 1 month and 80.8% at 1 year, a detailed analysis demonstrated.

While cranial nerve injury (CNI) is the most common neurologic complication of carotid endarterectomy, its reported incidence “is highly variable, ranging from 3% to 30% and depends on the intensity and the methods that are used for evaluation,” Dr. Robert J. Hye said at the annual meeting of the Western Vascular Society. “When using clinical criteria as in CREST, the incidence varies from 5% to 8%, and most injuries resolve in a few weeks. But in rare cases it can result in significant long-term disability.”

Most publications that have evaluated CNI discuss the frequency of nerve injury, not resolution or the time to healing. “Previous publications have identified prolonged operations, urgent operations, and re-exploration as predictors of CNI,” said Dr. Hye of the department of general and vascular surgery at Kaiser Permanente, San Diego. “Advocates of CAS [carotid artery stenting] have equated CNI with minor stroke, mitigating some of the benefit of CEA over CAS.”

He and his associates conducted the present study in an effort to evaluate the incidence, predictive factors, and resolution and also to compare health-related quality of life in patients with and without CNI in CREST, a trial conducted at 117 centers in the United States and Canada in which 2,502 patients were randomized to receive either CAS or CEA. Researchers in that trial observed no difference in outcome in the combined primary endpoint of stroke, MI, and death, but periprocedural stroke was significantly more common in the CAS group and periprocedural MI in the CEA group. Quality of life analyses were performed at 2 weeks, 1 month, and 12 months after the interventions (N. Engl. J. Med. 2010;363:11-23).

For the current analysis, patients with CNI were identified from the CREST database and classified using case report forms, adverse event reports, and clinical follow-up notes. Adjudication of the CNIs was performed by two neurologists and one vascular surgeon. Patients with only cutaneous sensory symptoms were excluded from analysis, and postprocedural outcomes were assessed at 30 days and 12 months. The researchers used the SF-36 and disease-specific Likert scales to measure health-related quality of life.

The mean age of patients at baseline was 68 years. Dr. Hye reported that CNI occurred in 53 of 1,151 (4.6%) randomized to CEA who received their operation within 30 days. CNIs were also noted in five additional patients: three who crossed over from CAS to CEA and two who did not undergo CEA within 30 days of randomization. In contrast to prior studies, CNI was significantly more common when general anesthesia was used, but there were no other demographic or procedural characteristics that were predictive of CNI. About one-third of CNIs (34%) were resolved at 30 days, and 80.8% were resolved at 1 year. CNI had a small effect on quality of life, negatively impacting only swallowing and eating at 2 and 4 weeks but not at 1 year (P less than .001).

Injuries to cranial nerves IX and X were most common, followed by injuries to the marginal mandibular branch of the facial nerve and the hypoglossal nerves. All of the hypoglossal injuries resolved, while injuries involving cranial nerves IX and X were least likely to resolve.

Dr. Hye acknowledged certain limitations of the trial, including the fact that CNI diagnosis was made from a clinical standpoint, and there were no routine otolaryngologic exams. “It’s likely that some of the subtle injuries were missed and that the incidence of cranial nerve injury is underestimated,” he added. “On the other hand, patients did have postoperative exams by experienced neurologists and vascular surgeons, so not many of the injuries should have been missed. Another unique thing about the study is the [quality of life] tools [we used]. They may be insufficiently sensitive to detect the consequences of CNI.”

Dr. Hye went on to note that the persistence of CNI at 1 year in CREST is higher than in most other reports available in the medical literature (19.2% vs. 7%-12%, respectively). “We’re not really sure why this is the case,” he said. “It may be that the postoperative assessment in CREST was more detailed and detected more subtle residual deficits from the CNIs.”

The study was funded by the National Institutes of Health, with supplemental funding from Abbott Vascular Inc. Dr. Hye reported having no financial disclosures.

[email protected]

On Twitter @dougbrunk

CORONADO, CALIF. – Cranial nerve injury occurred in 4.6% of patients who participated in the Carotid Revascularization Endarterectomy versus Stenting Trial (CREST), with 34% resolution at 1 month and 80.8% at 1 year, a detailed analysis demonstrated.

While cranial nerve injury (CNI) is the most common neurologic complication of carotid endarterectomy, its reported incidence “is highly variable, ranging from 3% to 30% and depends on the intensity and the methods that are used for evaluation,” Dr. Robert J. Hye said at the annual meeting of the Western Vascular Society. “When using clinical criteria as in CREST, the incidence varies from 5% to 8%, and most injuries resolve in a few weeks. But in rare cases it can result in significant long-term disability.”

Most publications that have evaluated CNI discuss the frequency of nerve injury, not resolution or the time to healing. “Previous publications have identified prolonged operations, urgent operations, and re-exploration as predictors of CNI,” said Dr. Hye of the department of general and vascular surgery at Kaiser Permanente, San Diego. “Advocates of CAS [carotid artery stenting] have equated CNI with minor stroke, mitigating some of the benefit of CEA over CAS.”

He and his associates conducted the present study in an effort to evaluate the incidence, predictive factors, and resolution and also to compare health-related quality of life in patients with and without CNI in CREST, a trial conducted at 117 centers in the United States and Canada in which 2,502 patients were randomized to receive either CAS or CEA. Researchers in that trial observed no difference in outcome in the combined primary endpoint of stroke, MI, and death, but periprocedural stroke was significantly more common in the CAS group and periprocedural MI in the CEA group. Quality of life analyses were performed at 2 weeks, 1 month, and 12 months after the interventions (N. Engl. J. Med. 2010;363:11-23).

For the current analysis, patients with CNI were identified from the CREST database and classified using case report forms, adverse event reports, and clinical follow-up notes. Adjudication of the CNIs was performed by two neurologists and one vascular surgeon. Patients with only cutaneous sensory symptoms were excluded from analysis, and postprocedural outcomes were assessed at 30 days and 12 months. The researchers used the SF-36 and disease-specific Likert scales to measure health-related quality of life.

The mean age of patients at baseline was 68 years. Dr. Hye reported that CNI occurred in 53 of 1,151 (4.6%) randomized to CEA who received their operation within 30 days. CNIs were also noted in five additional patients: three who crossed over from CAS to CEA and two who did not undergo CEA within 30 days of randomization. In contrast to prior studies, CNI was significantly more common when general anesthesia was used, but there were no other demographic or procedural characteristics that were predictive of CNI. About one-third of CNIs (34%) were resolved at 30 days, and 80.8% were resolved at 1 year. CNI had a small effect on quality of life, negatively impacting only swallowing and eating at 2 and 4 weeks but not at 1 year (P less than .001).

Injuries to cranial nerves IX and X were most common, followed by injuries to the marginal mandibular branch of the facial nerve and the hypoglossal nerves. All of the hypoglossal injuries resolved, while injuries involving cranial nerves IX and X were least likely to resolve.

Dr. Hye acknowledged certain limitations of the trial, including the fact that CNI diagnosis was made from a clinical standpoint, and there were no routine otolaryngologic exams. “It’s likely that some of the subtle injuries were missed and that the incidence of cranial nerve injury is underestimated,” he added. “On the other hand, patients did have postoperative exams by experienced neurologists and vascular surgeons, so not many of the injuries should have been missed. Another unique thing about the study is the [quality of life] tools [we used]. They may be insufficiently sensitive to detect the consequences of CNI.”

Dr. Hye went on to note that the persistence of CNI at 1 year in CREST is higher than in most other reports available in the medical literature (19.2% vs. 7%-12%, respectively). “We’re not really sure why this is the case,” he said. “It may be that the postoperative assessment in CREST was more detailed and detected more subtle residual deficits from the CNIs.”

The study was funded by the National Institutes of Health, with supplemental funding from Abbott Vascular Inc. Dr. Hye reported having no financial disclosures.

[email protected]

On Twitter @dougbrunk

CORONADO, CALIF. – Cranial nerve injury occurred in 4.6% of patients who participated in the Carotid Revascularization Endarterectomy versus Stenting Trial (CREST), with 34% resolution at 1 month and 80.8% at 1 year, a detailed analysis demonstrated.

While cranial nerve injury (CNI) is the most common neurologic complication of carotid endarterectomy, its reported incidence “is highly variable, ranging from 3% to 30% and depends on the intensity and the methods that are used for evaluation,” Dr. Robert J. Hye said at the annual meeting of the Western Vascular Society. “When using clinical criteria as in CREST, the incidence varies from 5% to 8%, and most injuries resolve in a few weeks. But in rare cases it can result in significant long-term disability.”

Most publications that have evaluated CNI discuss the frequency of nerve injury, not resolution or the time to healing. “Previous publications have identified prolonged operations, urgent operations, and re-exploration as predictors of CNI,” said Dr. Hye of the department of general and vascular surgery at Kaiser Permanente, San Diego. “Advocates of CAS [carotid artery stenting] have equated CNI with minor stroke, mitigating some of the benefit of CEA over CAS.”

He and his associates conducted the present study in an effort to evaluate the incidence, predictive factors, and resolution and also to compare health-related quality of life in patients with and without CNI in CREST, a trial conducted at 117 centers in the United States and Canada in which 2,502 patients were randomized to receive either CAS or CEA. Researchers in that trial observed no difference in outcome in the combined primary endpoint of stroke, MI, and death, but periprocedural stroke was significantly more common in the CAS group and periprocedural MI in the CEA group. Quality of life analyses were performed at 2 weeks, 1 month, and 12 months after the interventions (N. Engl. J. Med. 2010;363:11-23).

For the current analysis, patients with CNI were identified from the CREST database and classified using case report forms, adverse event reports, and clinical follow-up notes. Adjudication of the CNIs was performed by two neurologists and one vascular surgeon. Patients with only cutaneous sensory symptoms were excluded from analysis, and postprocedural outcomes were assessed at 30 days and 12 months. The researchers used the SF-36 and disease-specific Likert scales to measure health-related quality of life.

The mean age of patients at baseline was 68 years. Dr. Hye reported that CNI occurred in 53 of 1,151 (4.6%) randomized to CEA who received their operation within 30 days. CNIs were also noted in five additional patients: three who crossed over from CAS to CEA and two who did not undergo CEA within 30 days of randomization. In contrast to prior studies, CNI was significantly more common when general anesthesia was used, but there were no other demographic or procedural characteristics that were predictive of CNI. About one-third of CNIs (34%) were resolved at 30 days, and 80.8% were resolved at 1 year. CNI had a small effect on quality of life, negatively impacting only swallowing and eating at 2 and 4 weeks but not at 1 year (P less than .001).

Injuries to cranial nerves IX and X were most common, followed by injuries to the marginal mandibular branch of the facial nerve and the hypoglossal nerves. All of the hypoglossal injuries resolved, while injuries involving cranial nerves IX and X were least likely to resolve.

Dr. Hye acknowledged certain limitations of the trial, including the fact that CNI diagnosis was made from a clinical standpoint, and there were no routine otolaryngologic exams. “It’s likely that some of the subtle injuries were missed and that the incidence of cranial nerve injury is underestimated,” he added. “On the other hand, patients did have postoperative exams by experienced neurologists and vascular surgeons, so not many of the injuries should have been missed. Another unique thing about the study is the [quality of life] tools [we used]. They may be insufficiently sensitive to detect the consequences of CNI.”

Dr. Hye went on to note that the persistence of CNI at 1 year in CREST is higher than in most other reports available in the medical literature (19.2% vs. 7%-12%, respectively). “We’re not really sure why this is the case,” he said. “It may be that the postoperative assessment in CREST was more detailed and detected more subtle residual deficits from the CNIs.”

The study was funded by the National Institutes of Health, with supplemental funding from Abbott Vascular Inc. Dr. Hye reported having no financial disclosures.

[email protected]

On Twitter @dougbrunk

CORONADO, CALIF. – Intraoperative vessel assessment, not preoperative vein mapping, was more accurately associated with maturation and cumulative functional patency rates of arteriovenous fistulas, results from a 5-year, single-center retrospective study showed.

“The prevalence of chronic kidney disease has increased over the last 3 decades, and efforts by the Centers for Medicare & Medicaid Services and the National Kidney Foundation have sought to increase the use of fistulas,” Dr. Khanh P. Nguyen said at the annual meeting of the Western Vascular Society.

“Since 2003, the incidence and prevalence of fistulas have increased. More recently, even higher goals have been set. Arteriovenous fistulas are the preferred procedures due to higher patency rates, reduced rates of reintervention, and lower costs, compared with central venous catheters or grafts.”

Dr. Nguyen, formerly of Loma Linda (Calif.) Medical Center who is now a vascular surgery fellow at Oregon Health and Science University, noted that while many studies as well as the Society for Vascular Surgery have advocated the use of routine preoperative ultrasound in predicting the success of arteriovenous fistulas (AVFs), its use varies among vascular surgeons. “Given the additional costs and time of preoperative ultrasound, this study was undertaken to examine the use of this technique and compare it to intraoperative assessment,” she said.

The researchers examined all autologous AVFs created for patients with end-stage-renal disease at the Veterans Affairs Loma Linda Health System between February 2007 and July 2012. Preoperative ultrasound mapping of upper-extremity veins occurred, and patients were divided into two groups: those with veins less than 3 mm in size and those with veins 3 mm or greater in size. Subjective intraoperative evaluation was conducted by the operative surgeon, who rated the vein as either “good” or “poor” because of factors such as inadequate diameter, sclerosis, and calcification. Kaplan-Meier analysis was used to calculate maturation and patency rates.

Over the 5-year period, 387 fistulas were created in 361 patients. Of these, 198 had preoperative vein mapping; 36% were less than 3 mm in size, and 64% were 3 mm or greater in size.

By intraoperative assessment, 14% of patients were determined to have had poor vessels, and 86% were found to have good vessels. About half of the fistulas (51%) were created at the wrist. The average age of patients was 65 years, their mean body mass index was 28 kg/m², and their mean time on dialysis was 84 years. The majority (97%) were male.

Among patients with preoperative veins less than 3 mm in size or 3 mm in size or greater, the maturation and overall failure rates were similar at 71% vs. 75% (P = .61) and 68% vs. 58% (P = .15). However, among patients with assessments of poor or good veins at the time of operation, the maturation and overall failure rates were 42% vs. 82% (P < .001) and 86% vs. 54% (P < .001).

Subgroup analysis revealed that patients with good intraoperative evaluation, regardless of preoperative ultrasound findings, had higher maturation rates. “Likewise, patients with good intraoperative assessment, regardless of preoperative ultrasound findings, had higher cumulative functional patency rates. Of note, no patient who had both poor preoperative ultrasound and intraoperative assessments had a functional fistula at the time of last follow-up.”

Dr. Nguyen and her associates concluded that intraoperative vessel assessment, and not preoperative ultrasound, was more accurately associated with maturation and cumulative functional patency rates. “Even in patients with inadequate preoperative ultrasound vein mapping, intraoperative assessment may still be warranted,” she said. “If both preoperative and intraoperative assessments conclude that vessels are inadequate, do not create an AVF at that site.”

Dr. Nguyen reported having no relevant financial disclosures.

[email protected]

On Twitter @dougbrunk

CORONADO, CALIF. – Intraoperative vessel assessment, not preoperative vein mapping, was more accurately associated with maturation and cumulative functional patency rates of arteriovenous fistulas, results from a 5-year, single-center retrospective study showed.

“The prevalence of chronic kidney disease has increased over the last 3 decades, and efforts by the Centers for Medicare & Medicaid Services and the National Kidney Foundation have sought to increase the use of fistulas,” Dr. Khanh P. Nguyen said at the annual meeting of the Western Vascular Society.

“Since 2003, the incidence and prevalence of fistulas have increased. More recently, even higher goals have been set. Arteriovenous fistulas are the preferred procedures due to higher patency rates, reduced rates of reintervention, and lower costs, compared with central venous catheters or grafts.”

Dr. Nguyen, formerly of Loma Linda (Calif.) Medical Center who is now a vascular surgery fellow at Oregon Health and Science University, noted that while many studies as well as the Society for Vascular Surgery have advocated the use of routine preoperative ultrasound in predicting the success of arteriovenous fistulas (AVFs), its use varies among vascular surgeons. “Given the additional costs and time of preoperative ultrasound, this study was undertaken to examine the use of this technique and compare it to intraoperative assessment,” she said.

The researchers examined all autologous AVFs created for patients with end-stage-renal disease at the Veterans Affairs Loma Linda Health System between February 2007 and July 2012. Preoperative ultrasound mapping of upper-extremity veins occurred, and patients were divided into two groups: those with veins less than 3 mm in size and those with veins 3 mm or greater in size. Subjective intraoperative evaluation was conducted by the operative surgeon, who rated the vein as either “good” or “poor” because of factors such as inadequate diameter, sclerosis, and calcification. Kaplan-Meier analysis was used to calculate maturation and patency rates.

Over the 5-year period, 387 fistulas were created in 361 patients. Of these, 198 had preoperative vein mapping; 36% were less than 3 mm in size, and 64% were 3 mm or greater in size.

By intraoperative assessment, 14% of patients were determined to have had poor vessels, and 86% were found to have good vessels. About half of the fistulas (51%) were created at the wrist. The average age of patients was 65 years, their mean body mass index was 28 kg/m², and their mean time on dialysis was 84 years. The majority (97%) were male.

Among patients with preoperative veins less than 3 mm in size or 3 mm in size or greater, the maturation and overall failure rates were similar at 71% vs. 75% (P = .61) and 68% vs. 58% (P = .15). However, among patients with assessments of poor or good veins at the time of operation, the maturation and overall failure rates were 42% vs. 82% (P < .001) and 86% vs. 54% (P < .001).

Subgroup analysis revealed that patients with good intraoperative evaluation, regardless of preoperative ultrasound findings, had higher maturation rates. “Likewise, patients with good intraoperative assessment, regardless of preoperative ultrasound findings, had higher cumulative functional patency rates. Of note, no patient who had both poor preoperative ultrasound and intraoperative assessments had a functional fistula at the time of last follow-up.”

Dr. Nguyen and her associates concluded that intraoperative vessel assessment, and not preoperative ultrasound, was more accurately associated with maturation and cumulative functional patency rates. “Even in patients with inadequate preoperative ultrasound vein mapping, intraoperative assessment may still be warranted,” she said. “If both preoperative and intraoperative assessments conclude that vessels are inadequate, do not create an AVF at that site.”

Dr. Nguyen reported having no relevant financial disclosures.

[email protected]

On Twitter @dougbrunk

CORONADO, CALIF. – Intraoperative vessel assessment, not preoperative vein mapping, was more accurately associated with maturation and cumulative functional patency rates of arteriovenous fistulas, results from a 5-year, single-center retrospective study showed.

“The prevalence of chronic kidney disease has increased over the last 3 decades, and efforts by the Centers for Medicare & Medicaid Services and the National Kidney Foundation have sought to increase the use of fistulas,” Dr. Khanh P. Nguyen said at the annual meeting of the Western Vascular Society.

“Since 2003, the incidence and prevalence of fistulas have increased. More recently, even higher goals have been set. Arteriovenous fistulas are the preferred procedures due to higher patency rates, reduced rates of reintervention, and lower costs, compared with central venous catheters or grafts.”

Dr. Nguyen, formerly of Loma Linda (Calif.) Medical Center who is now a vascular surgery fellow at Oregon Health and Science University, noted that while many studies as well as the Society for Vascular Surgery have advocated the use of routine preoperative ultrasound in predicting the success of arteriovenous fistulas (AVFs), its use varies among vascular surgeons. “Given the additional costs and time of preoperative ultrasound, this study was undertaken to examine the use of this technique and compare it to intraoperative assessment,” she said.

The researchers examined all autologous AVFs created for patients with end-stage-renal disease at the Veterans Affairs Loma Linda Health System between February 2007 and July 2012. Preoperative ultrasound mapping of upper-extremity veins occurred, and patients were divided into two groups: those with veins less than 3 mm in size and those with veins 3 mm or greater in size. Subjective intraoperative evaluation was conducted by the operative surgeon, who rated the vein as either “good” or “poor” because of factors such as inadequate diameter, sclerosis, and calcification. Kaplan-Meier analysis was used to calculate maturation and patency rates.

Over the 5-year period, 387 fistulas were created in 361 patients. Of these, 198 had preoperative vein mapping; 36% were less than 3 mm in size, and 64% were 3 mm or greater in size.

By intraoperative assessment, 14% of patients were determined to have had poor vessels, and 86% were found to have good vessels. About half of the fistulas (51%) were created at the wrist. The average age of patients was 65 years, their mean body mass index was 28 kg/m², and their mean time on dialysis was 84 years. The majority (97%) were male.

Among patients with preoperative veins less than 3 mm in size or 3 mm in size or greater, the maturation and overall failure rates were similar at 71% vs. 75% (P = .61) and 68% vs. 58% (P = .15). However, among patients with assessments of poor or good veins at the time of operation, the maturation and overall failure rates were 42% vs. 82% (P < .001) and 86% vs. 54% (P < .001).

Subgroup analysis revealed that patients with good intraoperative evaluation, regardless of preoperative ultrasound findings, had higher maturation rates. “Likewise, patients with good intraoperative assessment, regardless of preoperative ultrasound findings, had higher cumulative functional patency rates. Of note, no patient who had both poor preoperative ultrasound and intraoperative assessments had a functional fistula at the time of last follow-up.”

Dr. Nguyen and her associates concluded that intraoperative vessel assessment, and not preoperative ultrasound, was more accurately associated with maturation and cumulative functional patency rates. “Even in patients with inadequate preoperative ultrasound vein mapping, intraoperative assessment may still be warranted,” she said. “If both preoperative and intraoperative assessments conclude that vessels are inadequate, do not create an AVF at that site.”

Dr. Nguyen reported having no relevant financial disclosures.

[email protected]

On Twitter @dougbrunk

COPENHAGEN – Almost half of patients with mild cognitive impairment progressed to dementia within 1 year of undergoing either arthroplasty or coronary angiography, according to a small Australian study.

Baseline cognitive impairment appeared to be the main driver of progression, increasing the risk more than sevenfold – significantly more than age or heart attack, Lisbeth Evered, Ph.D., said at the annual Alzheimer’s Association International Conference.

"After 12 months, 42% met the criteria for dementia," said Dr. Evered, a researcher at the University of Melbourne. "The expected annual progression from mild cognitive impairment [MCI] to dementia would be about 10%-12% per year."

Her study included 67 patients with a mean age of 70 years. All had MCI at baseline, with a mean score of 23 on the Mini-Mental State Exam (MMSE). They underwent either arthroplasty (26 patients) or coronary angiography (41 patients).

A year after surgery, about 34% of the arthroplasty patients and 46% of the angiography patients had progressed to dementia. Baseline cognitive impairment was the only factor significantly associated with the change.

Postsurgical cognitive decline, both transient and long lasting, is a well-documented phenomenon, with studies going back to the late 1800s. Although the causative link isn’t entirely clear, anesthetics have long been implicated, said Dr. Evered. In animal models, some anesthesia drugs do seem to precipitate an Alzheimer’s-like amyloidosis and tau hyperphosphorylation.

More recent animal data suggest that inflammation might be a powerful influence.

"When a patient has surgery with a general anesthetic, they experience peripheral inflammation," Dr. Evered explained. "In a healthy normal brain, there’s plenty of cognitive reserve, and although there might be some cognitive decline afterward, the person won’t really notice and will certainly recover."

In a vulnerable brain, however, the inflammation may be amplified and may cause significant collateral damage that accelerates cognitive decline. "The problem is, we don’t know why they are vulnerable or what we might do about it," she noted.

The best approach now is to routinely assess cognition before surgery and monitor it afterward, Dr. Evered explained. "Then, the perioperative period is not something occurring in isolation," she noted. "We will be better able to identify those at risk and implement strategies to improve their outcomes."

In a video interview, Dr. Evered and Dr. Brendan Silbert of St. Vincent’s Hospital, Melbourne, discuss the study and its implications.

Dr. Evered had no financial disclosures

[email protected]

On Twitter @alz_gal

COPENHAGEN – Almost half of patients with mild cognitive impairment progressed to dementia within 1 year of undergoing either arthroplasty or coronary angiography, according to a small Australian study.

Baseline cognitive impairment appeared to be the main driver of progression, increasing the risk more than sevenfold – significantly more than age or heart attack, Lisbeth Evered, Ph.D., said at the annual Alzheimer’s Association International Conference.

"After 12 months, 42% met the criteria for dementia," said Dr. Evered, a researcher at the University of Melbourne. "The expected annual progression from mild cognitive impairment [MCI] to dementia would be about 10%-12% per year."

Her study included 67 patients with a mean age of 70 years. All had MCI at baseline, with a mean score of 23 on the Mini-Mental State Exam (MMSE). They underwent either arthroplasty (26 patients) or coronary angiography (41 patients).

A year after surgery, about 34% of the arthroplasty patients and 46% of the angiography patients had progressed to dementia. Baseline cognitive impairment was the only factor significantly associated with the change.

Postsurgical cognitive decline, both transient and long lasting, is a well-documented phenomenon, with studies going back to the late 1800s. Although the causative link isn’t entirely clear, anesthetics have long been implicated, said Dr. Evered. In animal models, some anesthesia drugs do seem to precipitate an Alzheimer’s-like amyloidosis and tau hyperphosphorylation.

More recent animal data suggest that inflammation might be a powerful influence.

"When a patient has surgery with a general anesthetic, they experience peripheral inflammation," Dr. Evered explained. "In a healthy normal brain, there’s plenty of cognitive reserve, and although there might be some cognitive decline afterward, the person won’t really notice and will certainly recover."

In a vulnerable brain, however, the inflammation may be amplified and may cause significant collateral damage that accelerates cognitive decline. "The problem is, we don’t know why they are vulnerable or what we might do about it," she noted.

The best approach now is to routinely assess cognition before surgery and monitor it afterward, Dr. Evered explained. "Then, the perioperative period is not something occurring in isolation," she noted. "We will be better able to identify those at risk and implement strategies to improve their outcomes."

In a video interview, Dr. Evered and Dr. Brendan Silbert of St. Vincent’s Hospital, Melbourne, discuss the study and its implications.

Dr. Evered had no financial disclosures

[email protected]

On Twitter @alz_gal

COPENHAGEN – Almost half of patients with mild cognitive impairment progressed to dementia within 1 year of undergoing either arthroplasty or coronary angiography, according to a small Australian study.

Baseline cognitive impairment appeared to be the main driver of progression, increasing the risk more than sevenfold – significantly more than age or heart attack, Lisbeth Evered, Ph.D., said at the annual Alzheimer’s Association International Conference.

"After 12 months, 42% met the criteria for dementia," said Dr. Evered, a researcher at the University of Melbourne. "The expected annual progression from mild cognitive impairment [MCI] to dementia would be about 10%-12% per year."

Her study included 67 patients with a mean age of 70 years. All had MCI at baseline, with a mean score of 23 on the Mini-Mental State Exam (MMSE). They underwent either arthroplasty (26 patients) or coronary angiography (41 patients).

A year after surgery, about 34% of the arthroplasty patients and 46% of the angiography patients had progressed to dementia. Baseline cognitive impairment was the only factor significantly associated with the change.

Postsurgical cognitive decline, both transient and long lasting, is a well-documented phenomenon, with studies going back to the late 1800s. Although the causative link isn’t entirely clear, anesthetics have long been implicated, said Dr. Evered. In animal models, some anesthesia drugs do seem to precipitate an Alzheimer’s-like amyloidosis and tau hyperphosphorylation.

More recent animal data suggest that inflammation might be a powerful influence.

"When a patient has surgery with a general anesthetic, they experience peripheral inflammation," Dr. Evered explained. "In a healthy normal brain, there’s plenty of cognitive reserve, and although there might be some cognitive decline afterward, the person won’t really notice and will certainly recover."

In a vulnerable brain, however, the inflammation may be amplified and may cause significant collateral damage that accelerates cognitive decline. "The problem is, we don’t know why they are vulnerable or what we might do about it," she noted.

The best approach now is to routinely assess cognition before surgery and monitor it afterward, Dr. Evered explained. "Then, the perioperative period is not something occurring in isolation," she noted. "We will be better able to identify those at risk and implement strategies to improve their outcomes."

In a video interview, Dr. Evered and Dr. Brendan Silbert of St. Vincent’s Hospital, Melbourne, discuss the study and its implications.

Dr. Evered had no financial disclosures

[email protected]

On Twitter @alz_gal

BOSTON – Preoperative high-dose methylprednisolone dramatically reduced inflammation and enhanced recovery after endovascular aortic repair without increased morbidity in a prospective, double-blinded randomized study.

The primary outcome of modified systemic inflammatory response syndrome (SIRS) developed in 92% on placebo and 27% given methylprednisolone (relative risk, 0.29; P less than .001).

The effect was particularly striking in patients with three or more SIRS criteria, with an overall number needed to treat of 1.5, Dr. Henrik Kehlet said at the annual meeting of the American Surgical Association.

Tempering the postoperative inflammatory response with methylprednisolone also significantly trimmed hospital stays from 3 to 2 days (P less than .001) and morphine requirements from 10 mg to 0 mg (P less than .001).

Medical morbidity was reduced in the methylprednisolone group, but not significantly (23% vs. 36%; P = .1), as was surgical morbidity (20% vs. 21%; P = 1.0).

Importantly, there was no sign of an increase in diagnosed (23% vs. 17%) or treated (1% vs. 3%) endoleaks on computed tomography scan among 146 patients evaluable at 3 months’ follow-up, said Dr. Kehlet, professor of perioperative therapy and head of the surgical pathophysiology section at Rigshospitalet, Copenhagen University, and the oft-described "father" of rapid recovery.

Patrice Wendling/Frontline Medical News

About 40%-60% of patients undergoing endovascular aortic repair (EVAR) will develop postoperative SIRS. Although there is limited surgical injury with the minimally invasive procedure, there is still a stress response because the prosthesis releases proinflammatory mediators from the thrombus in the aortic aneurysm, he explained.

Invited discussant Dr. Basil Pruitt of the division of trauma at the University of Texas Health Science Center, San Antonio, observed that the findings take on added import in light of a 7,500-patient study presented at the recent American College of Cardiology meeting showing that methylprednisolone conferred no significant benefit and was associated with a 15% increased risk of postoperative heart attack plus death when given during cardiac surgery with cardiopulmonary bypass. He also questioned whether the glucocorticosteroid lowered the metabolic rate, as this would impair wound healing, or induced hypoglycemia or glucose intolerance.

"Do those findings and the concerns noted above simply define patient groups in whom methylprednisolone should not be infused preoperatively or, alternatively, do they define a threshold of physiologic or operative insult beyond which the effect of methylprednisolone is outweighed by the magnitude of injury and the associated systemic inflammatory response syndrome?" he asked.

Dr. Kehlet responded that he was unable to determine why that particular abstract found increased morbidity, but noted that the same authors previously published a systematic review (Eur. Heart J. 2008;29:2592-600) supporting reduced morbidity with steroid use in cardiopulmonary bypass.

He added, "The effect may depend on the type of injury, as you mention; cardiopulmonary bypass [is] a very special injury with many mediators of the stress response, compared to other surgical operations. We need more studies. And, finally, if you want to find out about the real outcomes, you must integrate the pharmacologic intervention with an optimized, fast-track setup."

Dr. Kehlet said they did not measure metabolic rate, but that no clinical problem was observed in the limited number of diabetics (n = 22) in their study. This finding is also supported by a huge, multicenter Dutch trial, in which intraoperative high-dose dexamethasone was associated with higher postoperative glucose levels in cardiopulmonary bypass patients, but had no effect on diabetes in subgroup analyses or on the primary endpoint of major morbidity at 30 days (JAMA 2012;308:1761-7).

For Dr. Kehlet's single-center, double-blinded study, 153 patients undergoing EVAR for abdominal aortic aneurysm were randomly assigned to receive a preoperative single dose of placebo or what was described as a single "old-fashioned sepsis dose of methylprednisolone" at 30 mg/kg. The two groups were similar at baseline with respect to age, comorbidities, aneurysm size, thrombus volume, EVAR procedures, and blood loss.

A modified version of SIRS was assessed during the first 4 days after surgery and defined by two or more of the following criteria: fever of more than 38° C (100.4° F) or less than 36° C (96.8° F), heart rate of more than 90 beats per minute, respiratory rate of more than 20 breaths per minute or arterial carbon dioxide tension of less than 4.3 kPa (32.25 mm Hg), and a C-reactive protein (CRP) level of more than 75 mg/L. The traditional fourth SIRS criterion of leukocytosis was replaced with CRP level because glucocorticoids always lead to leukocytosis, Dr. Kehlet noted.

Among 150 evaluable patients, high-dose methylprednisolone almost completely eliminated the proinflammatory activities of interleukin (IL)-6 (186 pg/mL vs. 20 mg/dL; P less than .001), IL-8, and CRP.

Among other inflammatory parameters, methylprednisolone reduced soluble tumor necrosis factor receptor 1 levels, but did not modify the d-dimer response, metalloproteinase-9, or myeloperoxidase, he said.

By 3 months, mortality was similar at 3% in the methylprednisolone group and 1% in the placebo group (P less than .5).

"What we don’t know is what the optimal dose-response relationship is because we used a very high dose and, of course, this was only 150 patients, so the safety issues cannot be answered based on this study, but the results are promising for future large-scale studies in this interesting operation," Dr. Kehlet concluded.

Dr. Kehlet and his coauthors reported no financial disclosures.

The complete manuscript of this study and its presentation at the American Surgical Association’s 134th annual meeting, April 2014, in Boston, is anticipated to be published in the Annals of Surgery, pending editorial review.

[email protected]

BOSTON – Preoperative high-dose methylprednisolone dramatically reduced inflammation and enhanced recovery after endovascular aortic repair without increased morbidity in a prospective, double-blinded randomized study.

The primary outcome of modified systemic inflammatory response syndrome (SIRS) developed in 92% on placebo and 27% given methylprednisolone (relative risk, 0.29; P less than .001).

The effect was particularly striking in patients with three or more SIRS criteria, with an overall number needed to treat of 1.5, Dr. Henrik Kehlet said at the annual meeting of the American Surgical Association.

Tempering the postoperative inflammatory response with methylprednisolone also significantly trimmed hospital stays from 3 to 2 days (P less than .001) and morphine requirements from 10 mg to 0 mg (P less than .001).

Medical morbidity was reduced in the methylprednisolone group, but not significantly (23% vs. 36%; P = .1), as was surgical morbidity (20% vs. 21%; P = 1.0).

Importantly, there was no sign of an increase in diagnosed (23% vs. 17%) or treated (1% vs. 3%) endoleaks on computed tomography scan among 146 patients evaluable at 3 months’ follow-up, said Dr. Kehlet, professor of perioperative therapy and head of the surgical pathophysiology section at Rigshospitalet, Copenhagen University, and the oft-described "father" of rapid recovery.

Patrice Wendling/Frontline Medical News

About 40%-60% of patients undergoing endovascular aortic repair (EVAR) will develop postoperative SIRS. Although there is limited surgical injury with the minimally invasive procedure, there is still a stress response because the prosthesis releases proinflammatory mediators from the thrombus in the aortic aneurysm, he explained.

Invited discussant Dr. Basil Pruitt of the division of trauma at the University of Texas Health Science Center, San Antonio, observed that the findings take on added import in light of a 7,500-patient study presented at the recent American College of Cardiology meeting showing that methylprednisolone conferred no significant benefit and was associated with a 15% increased risk of postoperative heart attack plus death when given during cardiac surgery with cardiopulmonary bypass. He also questioned whether the glucocorticosteroid lowered the metabolic rate, as this would impair wound healing, or induced hypoglycemia or glucose intolerance.

"Do those findings and the concerns noted above simply define patient groups in whom methylprednisolone should not be infused preoperatively or, alternatively, do they define a threshold of physiologic or operative insult beyond which the effect of methylprednisolone is outweighed by the magnitude of injury and the associated systemic inflammatory response syndrome?" he asked.

Dr. Kehlet responded that he was unable to determine why that particular abstract found increased morbidity, but noted that the same authors previously published a systematic review (Eur. Heart J. 2008;29:2592-600) supporting reduced morbidity with steroid use in cardiopulmonary bypass.

He added, "The effect may depend on the type of injury, as you mention; cardiopulmonary bypass [is] a very special injury with many mediators of the stress response, compared to other surgical operations. We need more studies. And, finally, if you want to find out about the real outcomes, you must integrate the pharmacologic intervention with an optimized, fast-track setup."

Dr. Kehlet said they did not measure metabolic rate, but that no clinical problem was observed in the limited number of diabetics (n = 22) in their study. This finding is also supported by a huge, multicenter Dutch trial, in which intraoperative high-dose dexamethasone was associated with higher postoperative glucose levels in cardiopulmonary bypass patients, but had no effect on diabetes in subgroup analyses or on the primary endpoint of major morbidity at 30 days (JAMA 2012;308:1761-7).

For Dr. Kehlet's single-center, double-blinded study, 153 patients undergoing EVAR for abdominal aortic aneurysm were randomly assigned to receive a preoperative single dose of placebo or what was described as a single "old-fashioned sepsis dose of methylprednisolone" at 30 mg/kg. The two groups were similar at baseline with respect to age, comorbidities, aneurysm size, thrombus volume, EVAR procedures, and blood loss.

A modified version of SIRS was assessed during the first 4 days after surgery and defined by two or more of the following criteria: fever of more than 38° C (100.4° F) or less than 36° C (96.8° F), heart rate of more than 90 beats per minute, respiratory rate of more than 20 breaths per minute or arterial carbon dioxide tension of less than 4.3 kPa (32.25 mm Hg), and a C-reactive protein (CRP) level of more than 75 mg/L. The traditional fourth SIRS criterion of leukocytosis was replaced with CRP level because glucocorticoids always lead to leukocytosis, Dr. Kehlet noted.

Among 150 evaluable patients, high-dose methylprednisolone almost completely eliminated the proinflammatory activities of interleukin (IL)-6 (186 pg/mL vs. 20 mg/dL; P less than .001), IL-8, and CRP.

Among other inflammatory parameters, methylprednisolone reduced soluble tumor necrosis factor receptor 1 levels, but did not modify the d-dimer response, metalloproteinase-9, or myeloperoxidase, he said.

By 3 months, mortality was similar at 3% in the methylprednisolone group and 1% in the placebo group (P less than .5).

"What we don’t know is what the optimal dose-response relationship is because we used a very high dose and, of course, this was only 150 patients, so the safety issues cannot be answered based on this study, but the results are promising for future large-scale studies in this interesting operation," Dr. Kehlet concluded.

Dr. Kehlet and his coauthors reported no financial disclosures.

The complete manuscript of this study and its presentation at the American Surgical Association’s 134th annual meeting, April 2014, in Boston, is anticipated to be published in the Annals of Surgery, pending editorial review.

[email protected]

BOSTON – Preoperative high-dose methylprednisolone dramatically reduced inflammation and enhanced recovery after endovascular aortic repair without increased morbidity in a prospective, double-blinded randomized study.

The primary outcome of modified systemic inflammatory response syndrome (SIRS) developed in 92% on placebo and 27% given methylprednisolone (relative risk, 0.29; P less than .001).

The effect was particularly striking in patients with three or more SIRS criteria, with an overall number needed to treat of 1.5, Dr. Henrik Kehlet said at the annual meeting of the American Surgical Association.

Tempering the postoperative inflammatory response with methylprednisolone also significantly trimmed hospital stays from 3 to 2 days (P less than .001) and morphine requirements from 10 mg to 0 mg (P less than .001).

Medical morbidity was reduced in the methylprednisolone group, but not significantly (23% vs. 36%; P = .1), as was surgical morbidity (20% vs. 21%; P = 1.0).

Importantly, there was no sign of an increase in diagnosed (23% vs. 17%) or treated (1% vs. 3%) endoleaks on computed tomography scan among 146 patients evaluable at 3 months’ follow-up, said Dr. Kehlet, professor of perioperative therapy and head of the surgical pathophysiology section at Rigshospitalet, Copenhagen University, and the oft-described "father" of rapid recovery.

Patrice Wendling/Frontline Medical News

About 40%-60% of patients undergoing endovascular aortic repair (EVAR) will develop postoperative SIRS. Although there is limited surgical injury with the minimally invasive procedure, there is still a stress response because the prosthesis releases proinflammatory mediators from the thrombus in the aortic aneurysm, he explained.

Invited discussant Dr. Basil Pruitt of the division of trauma at the University of Texas Health Science Center, San Antonio, observed that the findings take on added import in light of a 7,500-patient study presented at the recent American College of Cardiology meeting showing that methylprednisolone conferred no significant benefit and was associated with a 15% increased risk of postoperative heart attack plus death when given during cardiac surgery with cardiopulmonary bypass. He also questioned whether the glucocorticosteroid lowered the metabolic rate, as this would impair wound healing, or induced hypoglycemia or glucose intolerance.

"Do those findings and the concerns noted above simply define patient groups in whom methylprednisolone should not be infused preoperatively or, alternatively, do they define a threshold of physiologic or operative insult beyond which the effect of methylprednisolone is outweighed by the magnitude of injury and the associated systemic inflammatory response syndrome?" he asked.

Dr. Kehlet responded that he was unable to determine why that particular abstract found increased morbidity, but noted that the same authors previously published a systematic review (Eur. Heart J. 2008;29:2592-600) supporting reduced morbidity with steroid use in cardiopulmonary bypass.

He added, "The effect may depend on the type of injury, as you mention; cardiopulmonary bypass [is] a very special injury with many mediators of the stress response, compared to other surgical operations. We need more studies. And, finally, if you want to find out about the real outcomes, you must integrate the pharmacologic intervention with an optimized, fast-track setup."

Dr. Kehlet said they did not measure metabolic rate, but that no clinical problem was observed in the limited number of diabetics (n = 22) in their study. This finding is also supported by a huge, multicenter Dutch trial, in which intraoperative high-dose dexamethasone was associated with higher postoperative glucose levels in cardiopulmonary bypass patients, but had no effect on diabetes in subgroup analyses or on the primary endpoint of major morbidity at 30 days (JAMA 2012;308:1761-7).

For Dr. Kehlet's single-center, double-blinded study, 153 patients undergoing EVAR for abdominal aortic aneurysm were randomly assigned to receive a preoperative single dose of placebo or what was described as a single "old-fashioned sepsis dose of methylprednisolone" at 30 mg/kg. The two groups were similar at baseline with respect to age, comorbidities, aneurysm size, thrombus volume, EVAR procedures, and blood loss.

A modified version of SIRS was assessed during the first 4 days after surgery and defined by two or more of the following criteria: fever of more than 38° C (100.4° F) or less than 36° C (96.8° F), heart rate of more than 90 beats per minute, respiratory rate of more than 20 breaths per minute or arterial carbon dioxide tension of less than 4.3 kPa (32.25 mm Hg), and a C-reactive protein (CRP) level of more than 75 mg/L. The traditional fourth SIRS criterion of leukocytosis was replaced with CRP level because glucocorticoids always lead to leukocytosis, Dr. Kehlet noted.

Among 150 evaluable patients, high-dose methylprednisolone almost completely eliminated the proinflammatory activities of interleukin (IL)-6 (186 pg/mL vs. 20 mg/dL; P less than .001), IL-8, and CRP.

Among other inflammatory parameters, methylprednisolone reduced soluble tumor necrosis factor receptor 1 levels, but did not modify the d-dimer response, metalloproteinase-9, or myeloperoxidase, he said.

By 3 months, mortality was similar at 3% in the methylprednisolone group and 1% in the placebo group (P less than .5).

"What we don’t know is what the optimal dose-response relationship is because we used a very high dose and, of course, this was only 150 patients, so the safety issues cannot be answered based on this study, but the results are promising for future large-scale studies in this interesting operation," Dr. Kehlet concluded.

Dr. Kehlet and his coauthors reported no financial disclosures.

The complete manuscript of this study and its presentation at the American Surgical Association’s 134th annual meeting, April 2014, in Boston, is anticipated to be published in the Annals of Surgery, pending editorial review.

[email protected]