A novel single step percutaneous access sheath: the initial human experience.

PURPOSE: A novel 1-step percutaneous access sheath NS has been developed that allows the insertion of a dilating balloon and renal access sheath in a single step. We present the initial human experience with this sheath. MATERIALS AND METHODS: We performed a retrospective chart and database review of the initial 30 consecutive patients undergoing percutaneous nephrostolithotomy using the NS. Data collected included patient demographics, operative and recovery parameters, and complications. RESULTS: Mean patient age was 50.4 years (range 11 to 81), mean body mass index was 31.63 kg/m(2) (range 17.1 to 65) and mean preoperative stone area was 6.23 cm(2) (range 1 to 14.6). Six and 3 patients had full and partial staghorn calculi, respectively. Access was achieved via the upper pole in 16 patients, middle pole in 7 and lower pole in 7. Mean operative time was 114.8 minutes (range 61 to 237). Mean estimated blood loss was 145.5 cc (range 10 to 500) and mean postoperative hospital stay was 4.89 days (range 2 to 14). A total of 23 patients (76.7%) had no residual calculi on postoperative computerized tomography, 5 (16.7%) had residual fragments 4 mm or less and 2 (6.7%) had residual stone fragments greater than 4 mm. There were no complications related to the NS. CONCLUSIONS: The NS is safe, easy to use and has potential advantages compared to currently available renal access sheaths.

Laparoscopic warm renal ischemia in the solitary porcine kidney model.

OBJECTIVES: To determine the effect of a laparoscopic approach on warm renal ischemia in the pig with a solitary kidney. Although the maximal safe duration for warm ischemia during open partial nephrectomy is commonly accepted to be 30 minutes, the maximal safe ischemic time during laparoscopic partial nephrectomy has not been previously determined. METHODS: Sixteen farm pigs underwent unilateral laparoscopic right nephrectomy. Two weeks later, the pigs underwent complete laparoscopic mobilization of the remaining left kidney and were randomized to complete hilar clamp times of 0, 30, 60, or 90 minutes. Serum creatinine was evaluated before right nephrectomy and at days 0, 2, 4, 7, 14, and 30 after renal ischemia during laparoscopy. All renal specimens were evaluated by an experienced nephropathologist in a blinded fashion. RESULTS: The serum creatinine remained stable at all points in the control and 30-minute ischemia groups. The serum creatinine level rose initially on days 2 and 4 in the 60-minute and 90-minute ischemia groups but returned to baseline by day 7. At harvest, no statistically significant difference was found among the groups in serum creatinine or histologic features. CONCLUSIONS: Renal ischemic times up to 90 minutes during laparoscopy were well tolerated by the solitary porcine kidney. Possible explanations for this finding include the protective effect of a solitary kidney and the potential protective effect of relative ischemic preconditioning provided by the pneumoperitoneum.