Microbiological monitoring of aortic aneurysm wall and contents during aneurysmectomy.

Fifty-six patients, ranging in age from 49 to 90 years, underwent abdominal aortic aneurysmectomy and had cultures taken from the aneurysm wall and atheromatous debris to identify possible microbiological sources of future graft infection. All patients received antibiotics before and after operation. Eleven (19.6%) of 56 cultures yielded bacterial growth. The most common organism isolated was Staphylococcus epidermidis (in six of 11 patients). Thirty-seven percent of the aneurysms cultured were symptomatic (expanding or ruptured); however, this group accounted for 54% (6/11) of the positive cultures. During an average follow-up period of 24.5 months (range, four to 82 months), no early or late graft infections were documented. A literature review demonstrated the same disparity between positive cultures obtained at aneurysmectomy and subsequent low graft-infection rate.