Ultrasound-guided quadratus lumborum block for postoperative analgesia in a pediatric patient with congenital hip dislocation: a case report.

Developmental dysplasia of the hip (DDH) is a common congenital pediatric orthopedic malformation that often requires open reduction combined with pelvic osteotomy, resulting in severe postoperative pain. Pediatric patients under 2 years old have immature anatomical and physiological characteristics, high sensitivity to opioid analgesics, and an inability to subjectively express pain, which makes perioperative analgesia and anesthesia management a major clinical challenge. Traditional opioid-based analgesic regimens carry a high risk of adverse reactions such as respiratory depression and restlessness, which hinder postoperative recovery. This case reports the optimized perioperative anesthesia and analgesia management strategy for a 19-month-old female infant (12 kg, ASA Ⅰ) with right DDH undergoing open hip reduction and pelvic osteotomy, and preliminarily explores the clinical application value, efficacy and safety of ultrasound-guided type Ⅱ QLB in infant DDH surgery. A composite anesthesia strategy of general anesthesia combined with ultrasound-guided type Ⅱ QLB (0.2% ropivacaine, 0.5 mL/kg, total 6 mL) was adopted, with optimized perioperative management including precise airway selection, targeted vital sign monitoring, and multimodal postoperative analgesia (PCIA+on-demand oral acetaminophen). Pain was evaluated using the FLACC behavioral scale, and vital signs and adverse reactions were closely monitored postoperatively. The infant's 24-hour postoperative FLACC scores were all ≤2 points without the need for rescue analgesics, with significantly reduced opioid consumption (intraoperative sufentanil 6 μg, 24-hour PCIA tramadol 70 mg) compared with traditional regimens. Vital signs remained stable postoperatively, with no adverse reactions such as restlessness, nausea/vomiting, urinary retention, or local hematoma. The infant achieved independent turning and sitting at 48 h postoperatively and was discharged uneventfully at 14 days with no long-term complications, and parental analgesia satisfaction was 9/10. Ultrasound-guided type Ⅱ QLB combined with general anesthesia is a safe and effective perioperative management strategy for infant DDH surgery, which addresses pediatric-specific perioperative analgesia challenges, reduces opioid-related adverse reactions, and improves postoperative comfort. Strict control of local anesthetic dosage, proficient ultrasound localization for immature pediatric anatomy, and multimodal analgesia are the key to successful perioperative management, which provides a valuable clinical reference for pediatric orthopedic anesthesia practice.