[Studies on renal function following cardiac operations--with special reference to postoperative cardiac function]

Effect of cardiac function on postoperative renal function was studied in 54 cases. These cases were divided into two groups according to postoperative cardiac function. Group A was good cardiac function group (27 cases; the value of C.I. was below 2.2L/min/m2 less than once through all examinations after operation). Group B was low cardiac function group (27 cases; the value of C.I. was below 2.2L/min/m2 more than twice through all examinations after operation). Significant differences were found in cardiac index, mean arterial pressure, left, arterial pressure and total vascular resistance in two groups. Significant differences were not found in urinary volume and FENa in two groups. In creatinine clearance and free water clearance significant differences were found from early postoperative period, and group A showed better renal function than group B. Serum Na, serum K and urinary Na:K ratio were not significantly different between two groups. Difference of plasma renin activity was not significant, but plasma aldosterone was significantly higher in group B than in group A during postoperative period. In group B, four patients developed nonoliguric acute renal failure, eventually resulting in MOF. The author concluded that postoperative cardiac function played the most important role on the state of postoperative renal function.