Comparison of Ultrasound Versus Ultrasound With Nerve Stimulation-Guided Obturator Nerve Block to Prevent Adductor Spasm in Patients Undergoing Transurethral Resection of Bladder Tumor: A Randomized Controlled Study

Abstract

Background This study aimed to compare ultrasound versus ultrasound with nerve stimulation-guided obturator nerve block (ONB) for the prevention of adductor spasm in patients undergoing transurethral resection of bladder tumor (TURBT). Methodology This randomized controlled study included 240 adult patients in the age group of 30 to 70 years undergoing TURBT for lateral and posterolateral wall bladder tumors who fulfilled the American Society of Anesthesiologists grade I and II criteria. The patients were divided into two groups: group U (n = 120) included patients who underwent ONB using an ultrasound-guided technique and group UN (n = 120) included patients who underwent ONB using ultrasound with the nerve stimulation technique. Block performance time, adductor jerks/spasms, adductor muscle power, and patient and surgeon satisfaction were compared. A P-value <0.05 was considered statistically significant. Results The mean block performance time in group U was significantly less (4.4 ± 0.82 minutes) than in group UN (6.55 ± 0.37 minutes). Compared to group U, group UN had significantly fewer adductor jerks/spasms during the surgery (7.76% vs. 20.35%, p = 0.006), significantly more surgeon satisfaction (92.24% vs. 79.65%, p = 0.006), significantly more patient satisfaction (92.24% vs. 79.65%, p = 0.006), and comparable complications (excessive bleeding and minor bladder injury) and adductor muscle power after the block (p > 0.05). Conclusions ONB using the nerve stimulation technique under ultrasound guidance has a longer mean block performance time, a higher success rate, and higher surgeon satisfaction than ONB under ultrasound guidance only.

Keywords: adductor spasm; obturator nerve; onb; turbt; ultrasound.

Figure 1. Comparison of adductor jerks/spasms during surgery between groups U and UN.

Figure 2. Comparison of block performance time (in minutes) between groups U and UN.

Figure 3. The white arrow shows the needle and the red arrowhead shows the needle tip between the adductor longus and adductor brevis to block the anterior branch of the obturator nerve.

Figure 4. White arrows show the needle and the red arrowhead shows the needle tip between the adductor brevis and adductor magnus to block the posterior branch of the obturator nerve.