Artery, periarterial adipose tissue, and blood microbiology during vascular reconstructive surgery: perioperative and early postoperative observations

The presence and clinical significance of bacteria in the arterial wall, periarterial adipose tissue, and blood samples acquired during elective vascular operations were assessed in this study. Specimens were obtained from a random series of 84 patients (56 men, 28 women) undergoing 75 primary and 9 secondary arterial reconstructions. Operations performed most frequently included abdominal aortic aneurysmectomy (42), aortofemoral bypass reconstruction (15), and lower extremity bypass surgery for occlusive disease (7). Perioperative antibiotics were administered to all but one patient. A sample of artery, adjacent adipose tissue, and blood were obtained for microbial analysis during the vascular anastomosis or arteriotomy. This yielded a total of 152 artery, 139 adipose tissue, and 129 blood samples for study. Each specimen was divided and placed in blood agar plates, thioglycolate broth, and brain-heart infusion broth. Tissues yielding growth of the same organism(s) in two or more different media were considered positive for the presence of bacteria. Bacteria were present in at least one of the three tissues studied in 32/84 patients (38%). The frequency of positive cultures in primary (29/75, 39%) and secondary procedures (3/9, 33%) were similar. One positive culture site occurred in 26/32 (81%) patients, two positive culture sites existed in 5/32 (16%) patients, and three positive sites were found in 1/22 (3%) patients. Eighteen individual artery (18/152, 12%) and 19 adipose tissue samples (19/139, 14%) harbored bacteria, whereas only two blood cultures were positive (2/129, 2%). Organisms identified included coagulase-negative staphylococci (71%), gamma-streptococci (7%), diphtheroids (7%), Micrococcus (5%), alpha-streptococci (5%), Staphylococcus aureus (2%), and Pseudomonas picketti (2%).(ABSTRACT TRUNCATED AT 250 WORDS)