Off-pump surgery does not eliminate microalbuminuria or other markers of systemic inflammatory response to coronary artery bypass surgery

To evaluate whether off-pump surgery attenuates microalbuminuria and other markers of systemic inflammatory response to coronary artery bypass surgery as compared to surgery performed using cardiopulmonary bypass.Forty-three adult patients undergoing elective coronary artery bypass grafting surgery were operated on with or without cardiopulmonary bypass (CPB). Microalbuminuria, serum C-reactive protein, and oxygenation and lung function parameters were measured at several time points until the first postoperative morning.The urinary albumin/creatinine ratio was low in both groups before surgery, but reached a maximum level at the end of CPB or just after opening the last coronary artery clamp in the off-pump group (p0.05). The urinary albumin/creatinine ratio remained slightly elevated in both groups until the morning after the operation (p0.05). There were no statistical differences between groups. Serum C-reactive protein remained at the initial level the evening after the operation, but increased by the first postoperative morning in both groups (p0.001). The alveolar-arterial gradient for oxygen partial pressure rose significantly after the operation in the intensive care unit in both groups (p0.0001). The shunt fraction of the pulmonary circulation did not change in either group.Off-pump coronary artery surgery did not prevent the acute phase inflammatory response measured in the present study. The acute phase inflammatory response after coronary artery bypass surgery is more likely a response to the surgical trauma itself rather than to CPB.