Enhancement of bupivacaine caudal analgesia using nalbuphine compared with fentanyl in children undergoing inguinal hernia repair

Introduction
General anaesthesia in paediatrics is used usually accompanied with caudal block (CB) to allow for rapid and smooth recovery from anaesthesia and also for better control of pain associated with various surgical interventions especially those in the lower half of the body. However, CB using local anaesthetics alone provides short duration of analgesia. Therefore, various additives are being tested for providing longer duration of pain control. Opioids are one of the most beneficial additives to local anaesthetics in CB. Some researchers studied the analgesic efficacy of adding fentanyl or nalbuphine to different local anaesthetics in separate studies. In this trial, we wished to compare effects of adding fentanyl or nalbuphine to the local anaesthetic (bupivacaine: 0.125%) in single-shot CB.
Patients and methods
A total of 60 children scheduled for hernia repair operations under general anaesthesia combined with combined anaesthesia were divided into three groups: group C received caudal bupivacaine plus normal saline, group N received caudal bupivacaine plus nalbuphine and group F received caudal bupivacaine plus fentanyl. Anaesthesia was maintained with sevoflurane. Intraoperative standard monitoring was denoted every 15 min till the end of surgery which was allowed to start 15 min after caudal injection. Postoperatively, haemodynamics, pain score, adverse effects, sedation and agitation state were assessed.
Results
There were significant differences in postoperative pain score and sedation as group N had prolonged analgesia and prolonged sedation time than group F and group C with comparable incidence of adverse effects.
Conclusion
Adding nalbuphine 0.2 mg/kg to bupivacaine 0.125% provides better postoperative pain control than adding fentanyl 1 μg/kg to bupivacaine in the same concentration with comparable incidence of adverse effects.