Abdominal aortic aneurysms--a study of factors influencing postoperative mortality. Norwegian Aortic Aneurysm Trial.

Factors which influenced outcome after surgery have been studied in 444 patients with abdominal aortic aneurysm included in a Norwegian multicentre study. Two-hundred and seventy-nine patients were treated electively, 51 had impending rupture and 114 had a ruptured aneurysm. In the elective group age, a large aneurysm, impaired renal function, the presence of angina pectoris and intraoperative blood loss of more than 4 units were found to significantly increase hospital mortality. In the impending rupture group excess blood loss during the operation had a negative influence on hospital death but the limited number of patients in this group restricts the value of analysis. A low systolic blood pressure and an older patient were the only 2 risk factors which had a detrimental effect on postoperative survival in the ruptured group. The formulation of a risk index for these patients was not possible although Odds ratios for the individual factors found to be of importance may give some risk estimates.