Hypoalbuminemia Predicts Perioperative Morbidity and Mortality After Infrainguinal Lower Extremity Bypass for Critical Limb Ischemia

Background: Poor nutritional status has been associated with a higher risk of morbidity and mortality in general surgery patients; however, outcomes in vascular surgery patients are unclear. Our goal was to determine the effect of poor nutritional status on perioperative morbidity and mortality after lower extremity bypass (LEB).

Methods: The 2005-2012 National Surgical Quality Improvement Program was analyzed to determine associated complications, mortality, length of stay (LOS), and readmissions for patients with hypoalbuminemia (serum albumin <3.5 g/dL and <2.8 g/dL) undergoing infrainguinal lower extremity bypass for critical limb ischemia. Multivariable analyses were performed to assess associated risk factors while adjusting for possible confounders.

Results: There were 5,110 LEB identified with an albumin level recorded. There were 2,327 (45.5%) patients with a low preoperative albumin. Patients with a low albumin were more likely to have diabetes, chronic obstructive pulmonary disease, congestive heart failure, previous myocardial infarction, renal failure, dialysis dependence, hypertension, history of transient ischemic attack or stroke, steroid use, impaired functional status, dyspnea at rest, anemia, prior operations within 30 days, preoperative wounds or infections, and a tibial target (P < 0.05). Multivariable analyses showed that low albumin was independently associated with increased mortality (odds ratio [OR]: 1.8, 95% confidence interval [95% CI]: 1.3-2.6, P = 0.001), return to the operating room (OR: 1.4, 95% CI: 1.2-1.6, P < 0.001), and increased LOS (MR: 1.2, 95% CI: 1.1-1.2, P < 0.001). When compared with patients with normal albumin, patients with more severe hypoalbuminemia, less than 2.8 g/dL, showed further increased risk of mortality (OR: 2.5, 95% CI: 1.6-3.8), return to the operating room (OR: 1.6, 95% CI: 1.3-2.0), and prolonged LOS (MR: 1.2, 95% CI: 1.2-1.3).

Conclusions: Poor preoperative hypoalbuminemia is associated with morbidity and mortality after infrainguinal lower extremity bypass for critical limb ischemia. Evaluation and optimization of nutritional status should be performed preoperatively in this high risk population.