Background: The small but finite risk of postsplenectomy sepsis is generally regarded as a firm indication for splenic preservation after iatrogenic injury, especially in the young. But splenectomy may be preferable in patients who sustain splenic injuries during vascular operations because of the potential for continued bleeding associated with anticoagulation. The purpose of this study was to determine the perioperative morbidity of incidental splenectomy among patients undergoing abdominal vascular operations. Study Design: We studied 17 patients who underwent incidental splenectomy at the time of abdominal vascular operations. Complete data collected on each subject included preoperative and postoperative blood counts, operative indications and details, transfusion requirements, length of hospital stay, and outcomes. Using age- and gender-matched case controls undergoing identical vascular operations from the same period, we evaluated the complication rate and outcomes of patients who underwent splenectomy for iatrogenic injuries of the spleen, versus those who did not sustain splenic injuries. Results: The estimated prevalence of iatrogenic splenic injury during the study period was 0.5%. Mean operative time, estimated blood loss, and duration of mechanical ventilation tended to be greater in the splenectomy patients, but the differences did not achieve statistical significance. Splenorrhaphy was attempted in seven patients, but continued bleeding mandated spleen removal in all cases. Splenectomy patients had a higher transfusion requirement (p = 0.03) and a longer mean length of stay (p = 0.03) than controls. Compared with controls, there was a higher prevalence of infectious complications in the splenectomy patients (p = 0.015), but there was no difference in the prevalence of thromboembolic complications between groups. Two of the splenectomy patients died in the postoperative period from multisystem organ failure, and one died of a missed splenic injury Conclusions: These data suggest that incidental splenectomy during abdominal vascular operations is associated with increased postoperative infectious complications and prolonged hospitalization.