Analgesic effect of clonidine added to bupivacaine 0.125% in paediatric caudal blockade

BACKGROUND: Caudals are a common method of providing pain relief in children undergoing surgery. Clonidine, an alpha(2) agonist, exhibits significant analgesic properties. The current investigation sought to determine whether caudal clonidine added to caudal bupivacaine would decrease pain in paediatric patients undergoing surgery. METHODS: Thirty-six children undergoing elective surgery were studied. Following anaesthetic induction, a caudal was placed (1 mg.kg(-1) bupivacaine 0.125%) with an equal volume of either clonidine (2 microg.kg(-1)) or saline. Perioperative analgesic requirements in the postanaesthesia care unit (PACU) and at home following hospital discharge, and parental pain scores were evaluated. RESULTS: There were no significant demographic, haemodynamic, or pain score differences between the groups. There was no difference in analgesic duration between groups. There were significantly more children who vomited during the first 24 postoperative hours in the clonidine group than in the saline group (eight in clonidine, two in saline; P < 0.05). CONCLUSION: We do not recommend adding clonidine (2 microg.kg(-1)) to a bupivacaine (0.125%) caudal block in children undergoing surgery.