Questioning the wisdom of tubeless percutaneous nephrolithotomy (PCNL): a prospective randomized controlled study of early tube removal vs tubeless PCNL

Objective: To establish the efficacy of early removal of a nephrostomy tube after percutaneous nephrolithotomy (PCNL), to challenge the wisdom of tubeless PCNL, as we hypothesized that it would result in a shorter hospital stay, comparable benefit and safety, while maintaining the option of check nephroscopy ensuring far superior stone clearance.

Patients and methods: In all, 22 patients were prospectively randomized equally into two groups, group 1 (early nephrostomy removal) or group 2 (tubeless) during a 1-month study period. Inclusion criteria for the study were: a simple stone of <3 cm, no significant bleeding, no perforation, single-tract access and 'on-table' complete stone clearance. In group 1, a 20 F nephrostomy, 6 F retrograde ureteric catheter and a Foley catheter were used, while in group 2 only a 6 F retrograde ureteric catheter and Foley catheter were placed at the end of the procedure. Computed tomography (CT) with no contrast medium was done on the first morning after surgery before removing all catheters/tubes, and patients discharged subsequently. The variables assessed were stone clearance, hospital stay, analgesic requirement, postoperative complications and auxiliary procedures.

Results: The mean (SD) stone bulk was similar between the groups, at 2737 (946.9) and 2934.2 (2090.7) µL, respectively. Despite an on-table complete clearance, clearance assessed by CT was nine of 11 vs eight of 11 in groups 1 and 2, respectively. CT showed a 6 mm stone in one patient in group 1, while the remaining patients had stones of <4 mm. The mean (SD) analgesic requirement, haemoglobin decrease, urine leak and hospital stay in the two groups were 72.7 (51.8) vs 68.2 (46.2) mg of tramadol (P= 0.25), 1.6 (0.7) vs 1.6 (0.9) g/dL (P= 0.39), 13.9 (6.3) vs 7.1 (14.2) h (P= 0.018) and 72.8 (2.1) vs 70.2 (18.5) h (P= 0.09), respectively. Complications noted were early haematuria in none vs three (P= 0.21), urinoma none vs one, and fever in two vs one, respectively; one patient in group 1 required a check nephroscopy for a residual fragment. Overall clearance including re-treatment was 10/11 vs eight of 11 (P= 0.009), respectively.

Conclusion: Early tube removal after PCNL results in an equivalent analgesic requirement, decrease in haemoglobin and hospital stay as tubeless PCNL. It has a significantly lower incidence of early haematuria, better clearance rates and preserves the option of check nephroscopy. It can be considered as an accepted standard of care, with the preserved advantages of tubeless PCNL.