Comparison of Postoperative Pain Relief Impact between Caudal Bupivacaine Alone and Caudal Bupivacaine - Dexamethasone Mixture Administration for Pediatric Local Tube Urethroplasty

Abstract

Objective: To compare the postoperative analgesic influence between caudal bupivacaine only and caudal bupivacaine-dexamethasone combination administration in children undergoing local tube urethroplasty. Methods: This prospective, randomized and clinical trail investigation included 162 male pediatric patients, classed I by the American society of anesthesiologists, aged 11-14 years and assigned for local tube urethroplasty at Queen Rania Hospital, King Hussein Medical Center, Amman-Jordan, during the year of 2013. General anesthesia was induced using inhalational sevoflurane / oxygen anesthesia, after which a laryngeal mask airway was inserted and an intravenous line was secured. All subjects were repositioned to receive caudal sacral block using randomly either plain bupivacaine 0.25% mixed with normal saline 0.9% (Group I, n=80) or plain bupivacaine 0.25% mixed with dexamethasone 0.1mg/kg (Group II, n=82), not exceeding a total volume of 0.5ml/kg and not exceeding a maximum dose of 2mg/kg of bupivacaine in both groups, dividing the total volume in ¾ for bupivacaine and ¼ for dexamethasone, saline or both. Postoperatively, in the recovery room, rectal paracetamol 10 mg/kg was administered if the numerical rating scale was more or equal to four. Postoperative analgesia quality was assessed. Statistical discrepancies between the two groups were evaluated using Students t and Chisquare tests. Variance was used to assess inter-group differences in changes of pain scores. A value of P<0.05 was considered significant. Results: Postoperative mean pain free period was significantly less in group I (186 min) than in group II (272 min) (P<0.05).The mean time to first rectal paracetamol dose was 192 min. in group II and 125 min. in group I (P<0.05).