Pulsatile cardiopulmonary bypass for patients with renal insufficiency

Pulsatile cardiopulmonary bypass has been shown to preserve renal function and could therefore have considerable clinical value in patients undergoing cardiac surgery with preoperative renal insufficiency, by protecting them from further postoperative renal deterioration. Our three-year experience with pulsatile bypass in 29 patients with a preoperative serum creatinine concentration over 1.7 mg/100 ml (mean 2.9, range 1.8-6.1 mg/100 ml) (greater than 150 mumol/l (mean 256, range 159-539 mumol/l] supports this premise. There were no renal deaths in the perioperative period and only two patients had irreversible postoperative deterioration in renal function; one died on day 3 of low-output syndrome and the other had rapidly progressive nephrosclerosis and died of that disease one year later. Postoperative oliguria occurred in the patient with low cardiac output and in only one other. This experience contrasts with our previous experience and that reported by others with non-pulsatile bypass in patients with renal insufficiency. We suggest that pulsatile bypass should be considered for cardiac surgery in patients with preoperative renal dysfunction.