Ultrasound-guided transverse abdominis plane versus ilioinguinal/iliohypogastric block for postoperative analgesia in pediatric inguinal surgery: a randomized comparative study

Ultrasound-guided ilioinguinal/iliohypogastric (IIIH) block and transverse abdominis plane (TAP) block are used for postoperative analgesia after pediatric inguinal surgery. The IIIH block is a targeted nerve block, whereas the TAP block is a fascial plane block that depends on local anesthetic spread. Comparative data remain useful for defining their respective roles in routine pediatric practice. To compare postoperative analgesic outcomes of ultrasound-guided anterior TAP block and ultrasound-guided IIIH block in children undergoing elective unilateral inguinal surgery. This prospective randomized single-blind study was conducted from March 2019 to February 2020. ASA physical status I-II children aged 6 months to 12 years scheduled for elective unilateral inguinal surgery were randomized to receive either an ultrasound-guided anterior TAP block or an ultrasound-guided IIIH block after standardized induction of general anesthesia. Both blocks were performed with 0.25% bupivacaine 0.3 ml/kg. Pain was assessed during the first six postoperative hours using the Children’s Hospital of Eastern Ontario Pain Scale (CHEOPS) and after discharge using the Postoperative Pain Measure for Parents (PPMP). The primary outcome was the requirement for rescue analgesia during the first six postoperative hours in the hospital. Secondary outcomes included the time to first rescue analgesic request, analgesic consumption at home during the first 24 postoperative hours, block performance time, adverse events, and parental satisfaction. Sixty patients were enrolled ( n = 30/group); one in the TAP group was excluded. Groups were comparable regarding demographics and surgical duration. Mean time to first analgesic rescue was 7.5 ± 3.2 h (TAP) vs. 8.0 ± 3.8 h (IIIH) ( P = 0.46). Analgesic consumption was similar in-hospital (paracetamol: 7 vs. 6 patients; P = 0.75) and at home (paracetamol: 24 vs. 22; P = 0.70). Block performance time was significantly shorter in the TAP group (90.0 ± 70.5 s) compared to the IIIH group (136.6 ± 78.8 s; P = 0.03). No adverse events or toxicity were observed. Ultrasound-guided anterior TAP block and ilioinguinal/iliohypogastric block showed no statistically significant difference in postoperative analgesia after pediatric unilateral inguinal surgery. TAP block was faster to perform, although the clinical significance of this difference remains uncertain given the trial’s superiority design. ClinicalTrials.gov NCT06701162, registered on November 14, 2024. Retrospectively registered.