The accuracy of computed tomography in the diagnosis of retroperitoneal blood in the presence of abdominal aortic aneurysm.

The use of computed tomography (CT) in the management of patients who are hemodynamically stable with symptoms suggestive of ruptured abdominal aortic aneurysm and in hemodynamically unstable patients without palpable or known aortic aneurysms was analyzed in a retrospective study. One hundred forty-two CT scans were performed; 48 patients had abdominal aortic aneurysms and 35 had no evidence of rupture or retroperitoneal blood. Ten patients had CT scans that showed evidence of rupture, and three patients had CT scans that were thought to be indeterminate for rupture, probably inflammatory. Forty patients underwent laparotomy. Excluding the three patients with inflammatory aneurysms, the results of CT scanning were compared with the findings at laparotomy. The sensitivity of CT scanning for the diagnosis of retroperitoneal blood in the presence of abdominal aortic aneurysm was 77% and the specificity was 100%, with an overall accuracy of 92%. An algorithm for the management of the patient with symptoms suggestive of a ruptured aneurysm is presented.