Abdominal aortic aneurysms. 1. Selection of patients and operative results.

Between 1958--1976 204 patients with abdominal aortic aneurysms were admitted to the surgical ward for evaluation. One hundred and thirty-eight patients were operated on, 7 died prior to operation and 59 patients were not recommended operation for different reasons. Elective surgery was performed in 60 patients and 78 underwent acute surgery. The aneurysm had ruptured in 40 of the acutely operated patients. The operative mortality was 33% for the whole series, 65% among the ruptured aneurysms and 10% for the planned operations. The early mortality diminished successively and was during the last 5-year period 4% for planned and 40% for emergency operations. The main causes of the early mortality was renal or cardiac insufficiency and abdominal or gastrointestinal haemorrhage. Intestinal infarction was the cause of death in two patients. Twenty-nine re-operations were made in 24 patients. Abdominal haemorrhage, gastro-intestinal bleeding or arterial embolus in the leg were the most common reasons for the re-operations. An analysis of the factors that may influence the operative mortality revealed that age, sex, pre-operative shock, re-operations and number of blood transfusions may be of importance for prediction of the survival. Previously known hypertension, infarction, myocardial ischaemia or the operation time did not seem to have any predictive value. The most common reasons for not recommending surgery were small aneurysms, technical inoperability, advanced age or severely complicating disease.