Ultrasound-guided caudal analgesia using fentanyl versus dexmedetomidine as an adjuvant for levobupivacaine in infraumbilical pediatric surgeries

Introduction Single-shot caudal analgesia is a useful technique in controlling postoperative pain in infraumbilical pediatric surgeries, although of a limited duration. The aim of this study was to evaluate the analgesic efficacy and rate of success when incorporating dexmedetomidine or fentanyl to levobupivacaine in ultrasound (U/S)-guided caudal block for infraumbilical surgeries. Patients and methods This prospective, randomized, double-blinded study was conducted on 63 pediatric patients undergoing infraumbilical surgeries, allocated into three groups to receive inhalational anesthesia with an appropriately sized laryngeal mask airway, followed by U/S-guided caudal epidural block using either only 0.25% levobupivacaine (L), or incorporating it with 1 μg/kg fentanyl (LF) or 1 μg/kg dexmedetomidine (LD) in a total volume of 0.7 ml/kg. Pain assessment using Children’s and Infants’ Postoperative Pain Scale (CHIPPS) score, time to first analgesic, and total analgesia required in the three groups and Ramsay sedation score were recorded. Hemodynamics and any adverse effects were also documented. Results None of the patients required intraoperative additional analgesia. A statistically significantly lower postoperative CHIPPS values with prolonged analgesic duration and time to rescue analgesia was observed in the levobupivacaine–fentanyl and levobupivacaine–dexmedetomidine groups (275±20.62 and 304.75±25.2, respectively) as opposed to the levobupivacaine only group (203.1±18), with an evident reduction in the total paracetamol dose required postoperatively (P<0.001). Arousable sedation time was significantly prolonged in the levobupivacaine–fentanyl and levobupivacaine–dexmedetomidine groups. Apart from pruritus and urine retention in the levobupivacaine–fentanyl group, no adverse events were recorded in all groups. Conclusion Caudal levobupivacaine combined with dexmedetomidine 1 μg/kg in pediatric patients undergoing infraumbilical surgeries provides prolonged postoperative analgesia comparable to levobupivacaine–fentanyl and superior to levobupivacaine alone, with reduced postoperative analgesic requirements and extended arousable sedation time. The use of U/S raises the safety and ensures the success of caudal block.