Jugular bulb desaturation during coronary artery surgery: a comparison of off-pump and on-pump procedures

Background. Conventional coronary artery bypass surgery has been associated with cerebral injury attributed to cardiopulmonary bypass (CPB) and surgical manipulation of the ascending aorta. Off-pump coronary artery surgery avoids these factors and could prevent cerebral injury. However, moving the heart from its natural position affects the circulation and could compromise cerebral oxygenation and perfusion. We set out to compare episodes of poor global cerebral oxygenation, defined as a jugular bulb saturation less than 50%, between patients randomized to off-pump or (conventional) on-pump coronary artery surgery. Methods. One hundred and eighty-seven patients were assigned randomly to off-pump or on-pump coronary artery surgery. Oxygen saturation in the jugular bulb (Sj(o2)) was measured during revascularization of the three main coronary vessels in the off-pump group, and at the start of CPB, before rewarming, and after rewarming in the on-pump group. We compared samples with jugular bulb with desaturation (Sj(o2)<= 50%) between treatment groups. Results. One hundred and seventy-five patients (81 in the off-pump group [93%] and 94 in the on-pump group [94%]) had complete jugular oxygen saturation data. Thirty-nine patients in the off-pump group (48%) and 25 patients in the on-pump group (27%) had one or more samples with desaturation during revascularization or CPB (odds ratio after adjustment for other factors, 0.39; 95% confidence interval, 0.21-0.73, P < 0.01). Conclusion. Jugular bulb desaturation occurs more frequently during off-pump coronary artery surgery than during conventional coronary artery surgery.