Influence of renal artery blood flow on renal function during aortic surgery.

Background. This study was undertaken to determine the true incidence of renal impairment after aortic surgery and its association with intraoperative fluctuations in renal artery blood flow and cardiac output. methods. Direct measurements of renal artery blood flow were undertaken with electromagnetic flowmetry in 19 patients undergoing elective in frarenal aortic surgery. Renal function was assessed before and after operation by measurement of creatinine clearance. Results. Twelve patients (63%) had renal impairment as defined by a 40% or greater reduction in creatinine clearance after operation. This group of patients had significantly lower renal artery blood flow during the period of aortic cross-clamping than had those who preserved their renal function (p<0.001)