Abdominal aortic aneurysms. Is there an association between surgical volume, surgical experience, hospital type and operative mortality? Members of the Norwegian Abdominal Aortic Aneurysm Trial.

The effects of number of operations, experience of the surgeon, and type of hospital on operative mortality have been studied in 444 patients treated for abdominal aortic aneurysms. In the elective group (n = 279) there was a significant difference in mortality between hospitals in which more than 10 such operations were done compared with those in which less than 10 were done during the study period (p = 0.05; odds ratio (OR) 2.7). In the ruptured group there was no statistically significant difference (p = 0.14; OR 1.9). In the elective group, units with vascular surgical experience had an operative mortality of 4.8% compared with 11.3% for other units (p = 0.05; OR 2.6). In the ruptured group the figures were 52.5% and 73.3% respectively (p = 0.03; OR 2.5). There was no difference in operative mortality between university, county and local hospitals. Outcome of treatment after operations for abdominal aortic aneurysm was related to number of operations carried out and experience, whereas the type of hospital seemed less important.