In the six centuries since mesenteric ischemia was first described, multiple factors have been investigated as predictors of bowel viability with little consensus. We retrospectively examined all cases of exploratory laparotomy for suspected bowel ischemia over an 8.5-year period. Patients were grouped into those who had a "positive laparotomy" with findings of bowel ischemia, bowel gangrene, or both (PL) and those who had a "negative laparotomy" with no evidence of compromised bowel (NL). Of the 114 patients, 86 (75%) were in the PL group and 28 (25%) in the NL group. The significant differences between the two groups were the higher prevalence of females in the PL group versus the NL group [71% vs. 50% (P = 0.04)] and the younger age in the NL group versus the PL group [64 +/- 19 vs. 76 +/- 14 (P = 0.0002)]. The groups did not significantly differ with respect to preoperative comorbidities and results of laboratory studies. Two patients in NL group had pneumatosis intestinalis on abdominal CT. One patient in PL group had a negative visceral angiogram. There was no difference in mortality between the groups. No single preoperative study reliably predicted positive findings at laparotomy in our series.