The records of 231 patients (189 men, 42 women) treated during the last decade for ruptured infrarenal abdominal aortic aneurysm were reviewed to evaluate complications and mortality rates and to determine if preoperative factors would preclude attempt at surgical repair. Mean age was 73.7 years (range, 50 to 95 years). Fifty-seven patients (24.7%) were greater than or equal to 80 years of age. Sixty-eight patients (29.4%) had known abdominal aortic aneurysm before rupture. Preoperative systolic blood pressure was less than or equal to 90 mm Hg in 155 patients (67.1%). Fifty-six patients (24.2%) had cardiac arrest before operation. The overall mortality rate from admission until the end of the hospital stay was 49.4% (114 of 231). Seventeen patients (7.4%) died in the emergency department, 40 (17.3%) in the operating room, 27 (11.7%) during the first 48 postoperative hours, and 30 (13.0%) died later but during the same hospitalization. The 30-day operative mortality rate was 41.6%. Mean age of those who died was higher (75.3 years) than of those who survived (72.2 years) (p less than 0.02). Of patients greater than or equal to 80 years, 43.9% survived. Survival was lower among women (35.7%) than men (54.0%; p less than 0.04). A high APACHE II score, a low initial hematocrit, preoperative hypotension, and chronic obstructive pulmonary disease were associated multivariately with increased mortality rates (p less than 0.02). However, 59 of the 155 patients (38.1%) with preoperative hypotension survived. Deaths were high (80.4%) among patients with cardiac arrest (45 of 56); still, 28.2% of patients (11 of 39) survived repair after cardiac arrest.(ABSTRACT TRUNCATED AT 250 WORDS)