Ultrasound-guided ilioinguinal-iliohypogastric nerve block versus intravenous tramadol for preventing catheter-related bladder discomfort after transurethral prostate surgery: a randomized controlled trial

Abstract Purpose Patients undergoing transurethral prostate surgery often experience catheter-related bladder discomfort (CRBD), which can significantly impairs postoperative recovery. The anatomical convergence between the ilioinguinal and iliohypogastric (II-IH) nerve pathways (T12–L2) and the bladder innervation provides a rationale for evaluating the II-IH nerve block as a potential treatment. This study aimed to investigate the efficacy of ultrasound-guided II-IH nerve block versus intravenous tramadol in reducing postoperative CRBD. Methods Ninety-four patients undergoing transurethral prostate surgery were equally randomized to receive either 1.5 mg/kg intravenous tramadol or bilateral ultrasound-guided II-IH nerve block with 15 mL of 0.375% ropivacaine per side before extubation. Intravenous tramadol was used as rescue medication for moderate-to-severe CRBD. The primary outcome was the overall incidence of CRBD within postoperative 24 h. Secondary outcomes included CRBD severity, pain scores, adverse events, patient satisfaction, hospitalization duration, and International Prostate Symptom Scores (IPSSs). Results The overall incidence of CRBD within postoperative 24 h was 56.5% in the II-IH block group versus 65.2% in the tramadol group, with an absolute risk difference of −8.70% (95% confidential interval: −24.71% to 10.92%; p = 0.393). Secondary outcomes, including the incidence of moderate-to-severe CRBD, pain scores at all assessed timepoints, rescue tramadol use, length of hospitalization, and IPSSs were comparable between the two groups (all p > 0.05). However, the II-IH block group demonstrated significantly lower incidences of adverse events (including nausea and vomiting, headache, dizziness, and dry mouth) and a higher proportion of extremely satisfied patients (all p < 0.05). Importantly, no nerve block-related complications were observed in the II-IH block group. Conclusions Ultrasound-guided II-IH nerve block appeared to be a comparable alternative to intravenous tramadol for reducing CRBD after transurethral prostate surgery, while offering a more favorable safety profile and higher patient satisfaction. Trial registration Chinese Clinical Trial Registry, ChiCTR2300078552. Registered 12 December 2023, https://www.chictr.org.cn/showproj.html?proj=209712