The Analgesic Efficacy of Ultrasound-Guided Quadratus Lumborum Block Versus Ultrasound-Guided Caudal Block for Hip Surgery in Pediatrics: A Prospective Randomized Study

Background: Ultrasound-guided quadratus lumborum (QL) block, is local anesthetic technique providing perioperative somatic, perhaps even visceral, analgesia for patients of all ages. The aim of this study is to evaluate the analgesic efficacy of ultrasound-guided anterior QL block versus ultrasound-guided caudal block in pediatric patients undergoing hip surgery.

Patients and Methods: This prospective, randomized study was carried out on seventy patients aged 1-7 years, of both with ASA physical status I or II scheduled for elective surgical correction of developmental dysplasia of hip (DDH).

Anterior QL Block Group: Patients received ipsilateral ultrasound-guided anterior QL block after induction of general anesthesia using of bupivacaine 0.25% (0.5 mL/kg).

Caudal Block Group: Patients received ultrasound-guided caudal block after induction of general anesthesia using of bupivacaine 0.25% (0.75 mL/kg). Postoperative pain scores were assessed on admission to PACU and at 1, 2, 4, 6, 8, 12, 18 and 24 h postoperative. Total intraoperative fentanyl (µg) consumption, total postoperative rescue analgesic (morphine) consumption, time to the first rescue analgesic administration and Parent satisfaction were assessed. Heart rate and mean arterial blood pressure had been recorded pre–operative, every 15 min intra-operative , and postoperative on admission to PACU and at 1, 2, 4, 6, 8, 12, 18 and 24 h postoperative. Any undesirable side effects during the first 24 hours such as, bradycardia, hypotension, local hematoma at the side of injection, nausea and vomiting had been recorded.

Results: The median FLACC score was significantly lower in anterior QL block group than caudal block group at 4,6,8 and 12h postoperative (P<0.001). Total intraoperative fentanyl (µg) consumption was insignificant different between both groups (P=0.862). Post-operative morphine consumption was significantly lower in anterior QL group compared to caudal group (P<0.001). Time to first postoperative analgesic requirement was significantly prolonged in anterior QL block group compared to caudal block group (P < 0.001). The incidence of nausea and vomiting was insignificantly different between both groups (P > 0.999).

Conclusions: Ultrasound-guided anterior QL block provided effective and long lasting postoperative analgesia than ultrasound-guided caudal block with lesser postoperative analgesic consumption in pediatric patients undergoing surgical correction of DDH.