Efficacy and safety of dexmedetomidine added to caudal bupivacaine in pediatric major abdominal cancer surgery.

BACKGROUND: Caudal analgesia has been prolonged by the addition of various adjuvants. Dexmedetomidine is a highly selective alpha-2 agonist with sedative and analgesic properties.

OBJECTIVE: To investigate the effect of addition of dexmedetomidine to 0.25% bupivacaine for caudal analgesia in children undergoing major abdominal cancer surgery.

STUDY DESIGN: A randomized double-blind trial.

SETTING: Academic medical center.

METHODS: Forty pediatric patients, aged 3 - 12 years, weighting 10 - 40 kg, and of American Society of Anesthesiologists (ASA) physical status I and II scheduled for major abdominal cancer surgeries under general anesthesia combined with caudal analgesia were enrolled. They were randomly allocated into 2 groups: Group I (BD): (n = 20) received 1 mL/kg bupivacaine 0.25% with dexmedetomidine 1 μg/kg and group II (B): (n = 20) received 1 mL/kg bupivacaine 0.25%. Heart rate (HR), mean arterial pressure (MAP), and oxygen saturation (SPO2) were recorded for 120 minutes. Pain was assessed immediately postoperative and at hours 2, 4, 6, 12, 18, and 24 of postoperative period by Face, Legs, Activity, Cry and Consolability (FLACC) score. Time to first request for analgesia and total analgesic consumption in the first 24 hours were recorded. The level of sedation was recorded using Ramsay's sedation scale [Intravenous acetaminophen 15mg/kg (perfalgan, Squibb)]. Adverse effects were recorded and treated.

RESULTS: There was significant reduction in FLACC score in group BD at 2, 4, 6, and 12 hours postoperatively compared to group B. At the eighteenth and twenty-fourth hour there was no significant difference. Time of the first rescue analgesic requirement was significantly prolonged in group BD compared to group B. The mean total consumption of rescue analgesia in the 24 hours of the postoperative period was significantly decreased in group BD (405.00 ± 215.03) mg when compared with group B (810.35 ± 200.93) mg.

LIMITATIONS: This study is limited by its small sample size.

CONCLUSION: Addition of dexmedetomidine (1 μg/kg) to caudal bupivacaine 0.25% (1 mL/kg) in pediatric major abdominal cancer surgeries achieved significant postoperative pain relief for up to 19 hours, with less use of postoperative analgesics, and prolonged duration of arousable sedation. Hemodynamic changes were statistically significant, yet of no clinical significance.