Comparison of caudal epidural block and ultrasonography-guided transversus abdominis plane block for pain relief in children undergoing lower abdominal surgery

• In children, CEB is limited by brief duration of action.
• Evidence on ultrasonography-guided TAP block for primary analgesia in children is scarce.
• As per our study, CEB confers longer postoperative analgesia.

Study objectiveWe conducted this study to compare the efficacy of caudal epidural block (CEB) vs ultrasonography-guided transversus abdominis plane (TAP) block for providing postoperative pain relief in children scheduled for lower abdominal surgery. Whereas the primary objective was to compare the duration of postoperative analgesia, the secondary objectives included comparative assessment (TAP vs CEB) of quality of pain relief in the first 24 hours postoperatively and rescue analgesia requirements.DesignRandomized-control, prospective, observer-blinded, 2-arm, single-center comparison.SettingOperating room, postoperative recovery area.PatientsEighty-children, aged 2-6 years, of American Society of Anesthesiologists physical status I/II scheduled to undergo unilateral lower abdominal surgery under general anesthesia.InterventionsThe recruited children were randomly allocated to receive under general anesthesia either CEB (group C, 0.75 mL/kg of 0.25% bupivacaine) or ultrasonography-guided administration of TAP block (group T, 0.5 mL/kg of 0.25% bupivacaine).MeasurementsIntraoperative: heart rate and noninvasive blood pressure; postoperative: pain profile, including duration of postoperative analgesia, quality of pain relief, and rescue analgesia requirements.Main resultsThe median duration of postoperative analgesia was significantly greater in children who received CEB than those who were administered TAP block (group C: 362.5 minutes [172.5-693.75] vs group T: 210 minutes [108.75-362.5]; P < .05). No difference was found in the incidence of postoperative pain up to 6 hours from the point of initiation of assessment (group C: 47.2% vs group T: 55.9%; P > .05). The children who received CEB experienced greater incidence of pain in the 6- to 24-hour postoperative interval than those administered TAP block (group C: 75% vs group T: 44.1%; P < .05). Although there was no difference in the rescue analgesia requirements, the number of children not requiring any rescue analgesia in the first 24 hours postoperatively was significantly higher in the TAP group (group C: n = 2 vs group T: n = 8; P < .05).ConclusionsIn children undergoing lower abdominal surgery, CEB provides a significantly prolonged duration of postoperative analgesia when compared with ultrasonography-guided TAP block.