Predictors of severe morbidity and death after elective abdominal aortic aneurysmectomy in patients with chronic obstructive pulmonary disease

Objective: This study sought to identify risk factors associated with an unfavorable outcome after elective abdominal aortic aneurysm (AAA) repair in patients with chronic obstructive pulmonary disease (COPD). Methods. The clinical records of 158 patients who underwent elective open AAA repair with COPD determined from preadmission International Classification of Diseases-ninth revision codes during a 12-year period at the University of Michigan were reviewed. Patients with uncomplicated outcomes (group I) were compared with those with unfavorable postoperative outcomes (group II). The unfavorable outcomes were defined as myocardial infarction, acute renal failure, worsening respiratory insufficiency necessitating tracheostomy, or death within 30 days of surgery. Logistic regression analyses of variables that were identified as being statistically significant in the univariate analysis were used to develop a predictive model of these events. Results. Group I included 133 patients (77 men, 56 women) with a mean age of 70.1 years, and group II included 25 patients (13 men, 12 women) with a mean age of 71.4 years. Preoperative factors statistically related (P = .002) to an unfavorable outcome in group II patients included: suboptimal COPD management (fewer prescribed inhalers), lower hematocrit, preoperative renal insufficiency, and coronary artery disease. Importantly, abnormal preoperative spirometry and arterial blood gases were not predictive of a poor outcome. Univariate analysis also revealed increased hospital (25 versus 13 days; P = .0001) and intensive care unit (14 versus 4 days; P = .001) length of stays and a greater need for prolonged ventilation (8 versus 1 day; P = .039) for group II patients compared with group I patients. The 30-day mortality rate in the entire experience was 3.2% (5/158). No specific variables associated with mortality were identified. Conclusion: Fewer prescribed inhalers, lower hematocrit, renal insufficiency, and coronary artery disease are preoperative factors associated with unfavorable outcomes after open elective surgical repair of AAA in patients with COPD. Intensive management of these factors may reduce the hazards of AAA operations in these patients. COPD alone should not be considered a deterrent to the surgical treatment of AAAs.