Renal function in patients undergoing cardiopulmonary bypass operations.

We evaluate short- and long-term effects on renal functional reserve of cardiopulmonary bypass in 11 patients. A selected group (persistence of renal functional reserve before operation) of 11 adult patients undergoing cardiopulmonary bypass for aorta-coronary bypass were studied. Renal functional reserve tests were performed in all patients before the operation, at postoperative day 9, and at 6 months after operation. Basal glomerular filtration rate did not show significant changes at 9 days and at 6 months after operation. On the contrary, renal functional reserve was absent at 9 days, but it was restored to preoperative levels at 6 months after operation. In conclusion, our data indicate that cardiopulmonary bypass probably causes renal damage that is not sufficient to influence routine renal function parameters.