Renal injury by companion kidney during hypothermic pulsatile perfusion

To study possible deleterious effects of traumatized kidneys on well harvested ones during hypothermic pulsatile perfusion, paired dog kidneys were monitored on two separate MOX-100 machines connected to pool a common perfusate. First kidneys were optimally harvested and baseline renal vascular resistance (RVR) calculated from pressure divided by flow (mm Hg/ml minute). After 1 hour second kidneys were added and observation was continued for an additional 3 hours. RVR in first kidneys increased immediately and doubled by 3 hours when ischemic traumatized second kidneys were added, 0.70 +/- 0.07 to 1.37 +/- 0.15 (p less than 0.001). No change in RVR was noted when second kidneys were optimally retrieved or if the dogs were heparinized prior to nephrectomy. Histological examination showed no evidence of vascular obstruction in any kidney, but only tubular necrosis in nonheparinized, traumatized second kidneys. Weight gain in optimally removed kidneys was 41%, but only 8% in ischemic kidneys. RVR decreased unexpectedly in ischemic kidneys during 3 hours of perfusion (p less than 0.01). Release of vasoactive substances by damaged kidneys and arteriovenous shunting may explain these findings. Separate perfusion systems seem to be justified when one of two cadaver kidneys is of marginal quality.