Physiological comparison of off-pump and on-pump coronary artery bypass grafting in patients on chronic hemodialysis

Objectives: Despite the long-term benefit, the operative results of conventional coronary artery bypass grafting for chronic hemodialysis patients remain unsatisfactory. The efficacy of off-pump coronary artery bypass grafting for hemodialysis patients is yet to be determined. The purpose of this study was to investigate the postoperative physiology of off-pump coronary artery bypass grafting for hemodialysis patients. Methods: Twenty-five hemodialysis cases who underwent isolated coronary artery bypass grafting were reviewed. Fifteen of these patients underwent off-pump coronary artery bypass grafting (off-group) and 10 underwent on-pump coronary artery bypass grafting (on-group). Comparisons were made in cardiac function (cardiac index and stroke volume index), respiratory function (AaDO2), hemodialysis management (blood urea nitrogen, creatinine, right atrial pressure, pulmonary wedge pressure), and bleeding tendency (postoperative blood loss and blood transfusion). Results: There was no operative mortality, but 3 major postoperative complications occurred (2 sternal wound infections in the off-group and 1 pneumonia in the on-group). There was no difference in cardiac index or stroke volume index. AaDO2 was significantly lower in the off-group. Plasma concentrations of blood urea nitrogen and creatinine were similar between groups. Right atrial pressure was lower and pulmonary wedge pressure tended to be lower in the off-group. Postoperative bleeding and blood transfusion were similar between groups. Conclusion: Our study confirmed that off-pump coronary artery bypass grafting is feasible for hemodialysis patients. Physiologic data showed that off-pump coronary artery bypass grafting might be effective in preserving postoperative lung oxygenation.