Transvesical Blockade of the Obturator Nerve to Prevent Adductor Contraction in Transurethral Bladder Surgery

Abstract

To evaluate the efficacy of transvesical obturator nerve block (ONB) in the prevention of obturator nerve reflex and leg jerking during transurethral resection of bladder tumors (TURBT). A total of 60 patients were studied, in whom the transurethral resection of tumors on the posterolateral bladder wall were performed under spinal anesthesia (SA). The patients were randomly divided into two groups. In the first group, we performed transvesical ONB and SA together, while the second group received only SA. The patients underwent TURBT using monopolar cautery. Incidence of leg jerking was registered and compared in these two groups. We used a nerve stimulator to detect the obturator nerve next to the lateral bladder wall. The obturator nerve was identified by its response to nerve stimulation. Then, 10 mL of 1% lidocaine was slowly injected through the working channel of a cystoscope. In the intervention group, 34 ONBs (4 bilateral and 26 unilateral) were tried. We could not detect the obturator nerve by nerve stimulation in six patients, and lidocaine injection was carried out blindly in these cases. One patient in the intervention group experienced adductor contraction. Among 30 patients in the control group, 5 patients had leg jerking, and in 2 patients, the procedure ended incompletely because of muscle spasm. Comparing these two groups, transvesical ONB effectively decreased leg jerking during TURBT (16.5% vs 3%; P < 0.05). Local blockade of the obturator nerve during cystoscopy is an effective method to avoid its stimulation in TURBT. It can be performed easily, and we did not experience any serious complication.