Bacterial translocation in patients undergoing abdominal aortic aneurysm repair

Bacterial translocation occurs in humans and is associated with an increased incidence of septic morbidity. The aims of this study were to determine the prevalence of bacterial translocation in patients undergoing open abdominal aortic aneurysm (AAA) repair and to identify any association with postoperative septic complications.

This was a prospective observational study in which patients undergoing aneurysm repair were assessed for evidence of bacterial translocation by culture of a mesenteric lymph node (MLN), small bowel serosal exudate and thrombus within the aneurysm. All postoperative septic complications were recorded.

A total of 51 patients was studied (40 men, 11 women; median age 72 years). Enteric bacteria were isolated from the MLNs of five patients (prevalence of bacterial translocation 10 per cent), one of whom also yielded growth from the serosal exudate. Septic morbidity occurred in four of five patients in whom bacterial translocation was identified, compared with nine of 46 in those without translocation (P = 0.013, Fisher's exact test, mid P). One patient in whom Escherichia coli was grown from the MLN developed an aortoenteric fistula, with a coliform species isolated from the graft.

This study suggests that bacterial translocation occurs in patients undergoing AAA repair. It is associated with an increased incidence of postoperative septic morbidity and provides a possible mechanism for infection of prosthetic aortic grafts.