How small can we go? Percutaneous nephrolithotomy using 6F nephroureteral catheter

OBJECTIVES To retrospectively examine our percutaneous nephrotithotomy pathway to determine the efficacy of a 6F antegrade nephroureteral catheter (NUC). METHODS The records of 99 consecutive patients who underwent percutaneous nephrolithotomy from 1998 to 2000 were reviewed. All patients were admitted the day before percutaneous nephrolithotomy and underwent placement of a nephrostomy tube. The following day, after balloon dilation of the access tract and performance of the procedure through a 30F sheath, an internal-external 6F NUC was left in place. Nephrostograms were performed on postoperative day 1, and, if negative for extravasation or residual stones, the stent was removed. The postoperative parameters included the length of stay, intravenous narcotic use, complications, and time to removal of the indwelling stent. RESULTS The average procedure time was 103 minutes (range 30 to 300), with a mean stone size of 1.7 cm. The average length of stay was 2.5 days, with postoperative intravenous narcotic use lasting 1.7 days. Of the 99 NUCs placed, 82% were removed by postoperative day 2. Eleven patients had either renal (n = 8) or ureteral (n = 3) extravasation requiring prolonged stenting, and nine had residual stones requiring a second-look procedure. Multivariate analysis demonstrated that prolonged narcotic use, days with an indwelling stent, and longer procedure times correlated significantly with a longer length of stay (P <0.001). The proportion of minor and major complications was 18% and 5%, respectively. CONCLUSIONS The results of our study have indicated that the 6F NUC minimizes postoperative intravenous narcotic use and expedites both recovery and discharge. Because it is the smallest nephroureteral catheter reported to date for this use, we recommend it be incorporated into prospective studies with validated pain questionnaires.