Randomized prospective evaluation of nephrostomy tube configuration: impact on postoperative pain

OBJECTIVE: Conduct a prospective randomized single-blind comparison of two nephrostomy catheter designs, evaluating specifically intraoperative placement and postoperative comfort. MATERIALS AND METHODS: The single-blind, prospective randomized trial was conducted with institutional review board approval. All patients undergoing percutaneous nephrolithotomy who gave informed consent were randomized to placement of either a Boston Scientific Flexima 8.3F pigtail nephrostomy tube #27-180 (PIG) or a Boston Scientific 8.2F nephroureteral stent #410-126 (NUS). Randomization was concealed from the surgeon until time of placement. Subjective intraoperative placement characteristics were rated by the surgeon on a scale of 1 = excellent, 2 = fair, 3 = good and 4 = poor. The patient's postoperative pain intensity was evaluated with a Visual Analog Pain Score (0 = no pain to 10 = worst pain). RESULTS: Nine patients were randomized to each group. The PIG group was rated significantly better than the NUS group with regards to ease of placement (p = 0.007) and radiopacity of the tube (p = 0.007) by surgeon. Visual analog pain scores on postoperative day one, was significantly lower in the PIG group (mean = 2+/-2) than the NUS group (mean = 5+/-1) (p = 0.004). The mean amount of intra-venous morphine equivalent given in the PIG group (mean = 1+/4 Eq morphine) was less on average compared to the NUS group (mean = 6+/13 Eq morphine), but the differences did not reach statistical significance (p = 0.06). CONCLUSIONS: Following percutaneous nephrolithotomy, use of a small pig-tail nephrostomy tube results in greater ease of placement and less postoperative pain than a nephroureteral catheter.