Faculty Bibliography

BACKGROUND:Extracorporeal membrane oxygenation (ECMO) is an important life-saving modality for patients with cardiopulmonary failure. Vascular complications, including clinically significant limb ischemia, may occur as a result of femoral artery cannulation for venoarterial (VA) ECMO. This study examines our institutional experience with femoral VA ECMO and the development of ipsilateral limb ischemia. METHODS:We performed a retrospective review of all consecutive patients undergoing femoral VA ECMO between 2011 and 2016. The primary endpoint was clinical evidence of limb-threatening ischemia. Multivariate logistic regression analysis was used to identify predictors for limb ischemia after cannulation. RESULTS:Between March 2011 and September 2016, 154 patients underwent femoral cannulation for VA ECMO. Overall in-hospital mortality was 59.7%. Clinically significant ipsilateral limb ischemia occurred in 34 (22%) patients; 7 required four-compartment fasciotomy, and 3 of these patients required amputation. On univariate analysis, a history of pulmonary disease, peripheral arterial disease, and stroke or transient ischemic attack was significantly associated with clinical limb ischemia. On multivariate analysis, younger age (odds ratio [OR], 0.96; 95% confidence interval [CI], 0.93-0.99), diabetes (OR, 2.77; 95% CI, 1.08-7.12), pulmonary disease (OR, 3.86; 95% CI, 1.38-10.78), and peripheral arterial disease (OR, 13.68; CI, 2.75-68.01) were associated with limb ischemia. Lack of prophylactic distal perfusion catheter and arterial cannula size were not independently associated with limb ischemia. CONCLUSIONS:Femoral ECMO cannulation can be associated with significant limb ischemia necessitating surgical intervention. Younger patients, as well as those with a history of diabetes, pulmonary disease, and peripheral arterial disease, may be at increased risk for this complication.

OBJECTIVE:The unplanned 30-day readmission rate is a marker of quality of patient care across many disciplines. Data regarding risk factors for unplanned readmission after major lower extremity amputation (LEA) are limited. We evaluated predictors of readmission at our institution after major LEA. METHODS:We conducted a retrospective review of all patients undergoing above-knee amputation (AKA) or below-knee amputation (BKA) between November 2009 and November 2014. Patient demographic variables were collected. Predictors of unplanned 30-day readmission and stump complications were determined by multivariable logistic regression. RESULTS:A total of 811 patients were identified (AKA, 325; BKA, 486). Of these, 739 patients were included in the final analysis after excluding 30-day decedents without readmission. The overall 30-day readmission rate was 28.8% (AKA 27.9%; BKA 29.4%; P = .730). Stump complications accounted for 28.6% of readmissions (16.5% of AKA; 35.8% of BKA; P = .004). Other common diagnoses included nonsurgical site infection (33.8%), exacerbation of congestive heart failure (7.0%), and diabetes-related complications (6.1%). Surgical intervention was performed on 61% of stump complications (35.9% of AKA readmitted with stump complications; 68.7% of BKA readmitted with stump complications). BKA stump complications were converted to AKAs in 34.1% of cases (3.2% of the total BKA). None of the AKA stump complications required a higher level of amputation (ie, hip disarticulation). Independent predictors of all 30-day readmission included coronary artery disease and end-stage renal disease. American Society of Anesthesiologists class 3 as compared with class 4 was protective. Independent predictors of 30-day readmission for stump complications included rest pain and BKA. Patients who underwent BKA, rest pain as an indication for amputation, and having an occluded bypass graft were predictors of having a stump complication requiring surgery. CONCLUSIONS:The 30-day readmission rate after major LEA is high, with wound infections accounting for a significant proportion of these readmissions. There was no difference in readmission rates based on level of amputation. Those undergoing BKA were more likely to present with stump complications requiring a surgical intervention, and often a higher level of amputation. Identification of high-risk patients may play a role in reducing postoperative readmissions and stump complications.

We present a case of an 82-year-old male with known radiocontrast media (RCM) hypersensitivity who was admitted to our hospital with gangrene of his right toe. The plan for revascularization of his lower extremity required an angiogram. This presented a management challenge as the patient had experienced 2 episodes of delayed anaphylaxis to Omnipaque (iohexol) RCM, and based on a literature review, there was no known or established precedent on a safe procedure in these situations. The patient was premedicated and given a graded dose challenge of an alternative RCM (iodixanol) prior to the radiographic study. He was given 1% of the total expected dose 1 hour before to the procedure and an additional 10% for the 30 minutes prior. He was then given the final dose in the operating room. Following angiogram, the patient was monitored for 18 hours in the postanesthesia care unit, with no adverse reactions. He was placed on a prednisone taper for 1 week, with daily diphenhydramine. The patient remained asymptomatic throughout the hospital course. This novel approach to RCM hypersensitivity management lends itself to a hope that graded dose challenges may play a greater role in the management of these patients.

OBJECTIVE:Above-knee amputations (AKAs) and below-knee amputations (BKAs) are associated with high postoperative mortality rates. In this study, we examined factors associated with 30-day, 90-day, and 1-year mortality in patients who underwent a major lower extremity amputation. METHODS:We queried a prospectively collected institutional database for all patients who underwent AKA or BKA with primary or secondary closure, during a 5-year period, between November 2009 and November 2014. Predictors of 30- and 90-day mortality were determined by multivariable logistic regression, and risk indexes for 1-year mortality were determined with Cox proportional hazards model. RESULTS:We identified 811 patients who underwent AKA (n = 325) or BKA (n = 486). The 30-day mortality was 8.4% (AKA, 13.5%; BKA, 4.9%; P < .001) and 90-day mortality was 15.4% (AKA, 24.3%; BKA, 9.45%; P < .001). Predictors of 30-day mortality included AKA (odds ratio [OR], 3.09; 95% confidence interval [CI], 1.76-5.53), emergency operation (OR, 2.86; 95% CI, 1.56-5.14), chronic obstructive pulmonary disease (OR, 3.09; 95% CI, 1.07-7.81), end-stage renal disease (ESRD) on hemodialysis (HD; OR, 2.35; 95% CI, 1.24-4.33), and chronic kidney disease stages 3 (OR, 1.84; 95% CI, 1.00-3.37) and 4 (OR, 2.33; 95% CI, 1.01-4.98). Predictors of 90-day mortality included age (OR, 1.02; 95% CI, 1.00-1.04), ESRD on HD (OR, 2.56; 95% CI, 1.55-4.22), AKA (OR, 2.61; 95% CI, 1.70-4.05), history of coronary artery bypass grafting (OR, 2.04; 95% CI, 1.06-3.87), and medium-intensity or high-intensity statin (OR, 0.46; 95% CI, 0.29-0.73). One-year survival for the overall cohort was 73.7% (95% CI, 70.8%-76.8%). Predictors of 1-year mortality included AKA (hazard ratio [HR], 2.07; 95% CI, 1.54-2.77), coronary artery bypass grafting (HR, 1.57; 95% CI, 1.07-2.32), age >70 years (HR, 1.39; 95% CI, 1.02-1.88), gangrene (HR, 1.44; 95% CI, 1.07-1.94), ESRD on HD (HR, 1.96; 95% CI, 1.42-2.70), chronic obstructive pulmonary disease (HR, 2.54; 95% CI, 1.52-4.25), Caucasian race (HR, 1.62; 95% CI, 1.18-2.22), history of open lower extremity revascularization (HR, 0.71; 95% CI, 0.51-1.00) and undergoing bilateral amputations (HR, 2.10; 95% CI, 1.06-4.15). In the year after amputation, medium-intensity statin (HR, 0.64; 95% CI, 0.47-0.87) and high-intensity statin (HR, 0.56; 95% CI, 0.33-0.95) conferred a mortality benefit. Low-intensity statins did not confer protection from mortality. At 1 year after amputation, only 44.7% of patients were receiving appropriate statin therapy. CONCLUSIONS:AKA and BKA have historically been associated with high mortality rates. Medium-intensity and high-intensity statin therapies were associated with a mortality benefit at 1 year. We have identified initiation of statin therapy in this high-risk population as a gap in patient care.

We report the case of a 78-year-old man with coronary artery disease, chronic obstructive pulmonary disease, and chronic renal insufficiency with an enlarging 6.7-cm infrarenal abdominal aortic aneurysm. He also had a 4-cm right common iliac artery aneurysm, and right external iliac artery occlusion. The patient had a history of an axillobifemoral bypass graft placed 10 years prior for aortoiliac occlusive disease. We describe the use of an infrarenal aorto-uni-iliac graft and subsequent intentional graft occlusion as an endovascular solution to treat aneurysmal disease in this sick patient. He remains asymptomatic after surgery, with demonstrated occlusion of his aneurysms.

Management of uncomplicated type B aortic dissection is traditionally medical with aggressive blood pressure management. However, a significant cohort of these medically managed patients develop the need for late intervention, contributing to long-term morbidity and mortality. While medical therapy remains best for most, evidence continues to mount supporting early intervention in subgroups of patients with certain anatomic characteristics and comorbidities