Addition of clonidine or dexmedetomidine to bupivacaine prolongs caudal analgesia in children

Caudal block is a common technique for paediatric analgesia but with the disadvantage of short duration of action after single injection. Caudal dexmedetomidine and clonidine could offer significant analgesic benefits. We compared the analgesic effects and side-effects of dexmedetomidine and clonidine added to bupivacaine in paediatric patients undergoing lower abdominal surgeries. Sixty patients (6 months to 6 yr) were evenly and randomly assigned into three groups in a double-blinded manner. After sevoflurane in oxygen anaesthesia, each patient received a single caudal dose of bupivacaine 0.25% (1 ml kg−1) combined with either dexmedetomidine 2 µg kg−1 in normal saline 1 ml, clonidine 2 µg kg−1 in normal saline 1 ml, or corresponding volume of normal saline according to group assignment. Haemodynamic variables, end-tidal sevoflurane, and emergence time were monitored. Postoperative analgesia, use of analgesics, and side-effects were assessed during the first 24 h. Addition of dexmedetomidine or clonidine to caudal bupivacaine significantly promoted analgesia time [median (95% confidence interval, CI): 16 (14–18) and 12 (3–21) h, respectively] than the use of bupivacaine alone [median (95% CI): 5 (4–6) h] with P