Abdominal aortic aneurysm rupture: statistical analysis of factors affecting outcome of surgical treatment

Abstract

One hundred sixteen patients underwent surgery for ruptured abdominal aortic aneurysms with intraoperative and overall mortality rates of 20.7% and 51.7%, respectively. The correlation of multiple factors to morbidity and mortality was assessed with detailed statistical analysis. Eight preoperative factors were identified as predictors of mortality. Increased intraoperative mortality rates were associated with heart disease (29%), hypertension (30%), flank ecchymoses (57%), and pulsatile abdominal mass (24%). Increased intraoperative and overall mortality rates were associated with preoperative hypotension (39%, 78%) and BUN levels higher than 30 mg/dl (47%, 82%). Increased overall mortality rates were associated with creatinine levels higher than 3 mg/dl (71%) and a hematocrit of 30.0 to 32.5 vol% (75%) (P less than 0.05). Seven intraoperative factors were identified as predictors of mortality. Increased postoperative mortality rates were associated with a duration of operation of more than 400 minutes (100%), hypotension lasting longer than 110 minutes (88%), estimated blood loss more than 11,000 ml (75%), blood transfusion more than 17 U (68%), fluid administration in excess of 7000 ml (70%), and a blood pressure lower than 100 mm Hg at the conclusion of the operation (88%). Cardiac arrest was associated with increased intraoperative and overall mortality rates (77%, 82%) (P less than 0.05). In general these factors cannot be controlled by the surgeon, and future significant reduction in the operative mortality rate may be possible. These findings support the general concept of aggressive elective resection of abdominal aortic aneurysms.