Complications in Transurethral Resection of the Bladder Tumor: Using Nerve Stimulator with or Without Ultrasonography for Obturator Nerve Block: A Comparative Study

The use of ultrasonographic guide is a suggested way to ease the obturator nerve block procedure. Accordingly, in this study, the procedures by selective obturator nerve block with and without use of ultrasonographic guide were compared.

This interventional study was performed as an open-label randomized clinical trial among 50 consecutive subjects under surgery for intramural tumors of urinary bladder in a training hospital in 2016. The subjects were randomly assigned to be operated under spinal anesthesia accompanied with selective obturator nerve block (10 mL of 1.5% lidocaine adding 1:200000 epinephrine) with or without ultrasonographic guide. The outcomes were compared across the groups.

There was no statistically significant difference between the onset time in group without guide (6.3 ± 2.2 minutes) and that in the guided group (5.9 ± 2.1 minutes). The time required for the nerve block (4.4 ± 1.3 minutes versus 1.7 ± 0.8 minutes) was significantly shorter (P = 0.001). There were less complications in the group with use of ultrasonographic guide showing significant difference (P = 0.01). The success rate in block was significantly higher in the group with ultrasonographic guide (100% versus 92%, P > 0.05).

Finally, according to the obtained results, it may be concluded that ultrasonography guidance would improve efficacy of obturator nerve block compared with conventional techniques.