Comparison of gastrointestinal complications in on-pump versus off-pump coronary artery bypass grafting

Background: Gastrointestinal (GI) complications following coronary artery bypass grafting (CABG), although infrequent, are associated with significant morbidity and mortality. It has been suggested that systemic inflammatory response plays an important role in these complications. Cardiopulmonary bypass (CPB) is well known to cause increased systemic inflammation, and therefore it has been proposed that performing CABG using an off-pump technique could substantially minimize the risk of GI complications. Prolonged CPB duration has been shown to be an independent predictor of GI complications; however, the effect of avoiding CPB altogether through off-pump procedures has not been thoroughly examined. We sought to compare the incidence of GI complications in patients undergoing on-pump and offpump CABG. Methods: We analyzed prospectively entered data on 2451 patients who underwent isolated CABG between January 2000 and October 2004. We compared GI complication rates in 5 predetermined areas (GI bleed, ileus, pancreatitis, ischemic bowel and cholecystitis) among patients who had on-pump CABG with those of patients who had off-pump CABG. We also compared in-hospital mortality due to these complications between the 2 groups. Results: We compared data for a total of 2010 patients in the on-pump group and 441 in the off-pump group. In the on-pump group, 30 (1.49%) patients experienced GI complications compared with 4 (0.91%) in the off-pump group (p = 0.34). Gastrointestinal bleed was the most common complication in the off-pump group. Eight patients in the on-pump group experienced ischemic bowels compared with no patients in the off-pump group. Six patients (0.3%) in the on-pump group died from GI complications, whereas no patients in the off-pump group died from such complications (p = 0.25). Conclusion: We found no significant difference in the total number of GI complications between the off-pump and on-pump groups; however, trends could be seen in the types of GI complications that occurred in the 2 groups. Owing to the relatively infrequent occurrence of GI complications, a larger scale study would be beneficial to determine whether the differences observed would be significant.