In-vitro renal shrinkage after hypertonic saline perfusion for organ removal during laparoscopic nephrectomy

To evaluate the possibility of shrinking the kidney by perfusion with hypertonic solution to facilitate organ removal in laparoscopic surgery.

After 18 open nephrectomies (ONs) in 9 pigs, one of four saline solutions (5%, 7.5%, 10%, and 15%) was infused through a catheter into the renal artery for 5 minutes in four kidneys each. The volumes and weights of the kidneys were measured before and after renal perfusion; the kidneys were then sent for histologic evaluation. Eight ONs were performed, and the kidneys were removed from the abdominal cavity in a plastic bag in order to mimic organ entrapment during laparoscopy. The kidneys were perfused with hypertonic solution and were again put in a plastic bag and removed from the same animal's abdomen through another incision. The incisions were measured with calipers before and after extraction of the unperfused and perfused organs.

The kidneys that underwent perfusion with 5% saline had the greatest decrease in both weight and volume, an average of 16% and 17.8%, respectively. The average incision needed for extraction of unperfused kidneys was 44.9 mm (range 40-58 mm), whereas the mean size of the incision needed to remove perfused kidneys was 26.6 mm (range 20-30 mm) (P < 0.001). The relative reduction in the necessary incision size therefore was 44.3% (range 33.3%-55%).

Perfusion with 5% saline is able to shrink the kidney volume slightly with mild histologic changes. In the pig, it is possible to decrease the renal incision necessary for kidney removal by 44% using this method.