Impact of nerve stimulator-guided obturator nerve block on the short-term outcomes and complications of transurethral resection of bladder tumour: A prospective randomized controlled study.

Introduction: In this prospective randomized controlled study, we investigated the efficacy of obturator nerve block (ONB) on adductor muscle spasm and related short-term outcomes and complications in patients who underwent transurethral resection of lateral wall-located bladder tumours (TURBT).

Methods: Between July 2014 and February 2015, 70 patients scheduled to undergo TUR of lateral bladder wall tumours were enrolled in the study. All patients were preoperatively evaluated by cystoscopy and imaging tools and selected according to localized tumours on the lateral bladder wall. Patients were randomly allocated to Group SA (35 patients who underwent only spinal anesthesia) and Group ONB (35 patients who underwent spinal anesthesia combined with ONB by the nerve stimulator). An independent observer, blinded to the approach, evaluated the obturator signs, including adductor muscle contraction, bladder perforation, and completeness of the resection during the TURBT procedure.

Results: The differences between groups regarding mean operation time, tumour size, and number were not statistically significant (p > 0.05). Adductor muscle contraction was detected in 40% of patients in Group SA and 11.4% in Group ONB. This difference was statistically significant (p = 0.021). Complete bladder perforation was detected in 2 patients in Group SA, whereas no perforation was observed in Group ONB. There was no case of severe bleeding in both groups.

Conclusions: We found that ONB performed after spinal anesthesia was effective in preventing intraoperative complications due to adductor muscle spasm while performing TURBT. Our study limitations include its small sample size, since we only enrolled patients with primary lateral wall-localized bladder tumour. Also, we excluded patients who underwent bipolar TURBT.