Comparison of Bupivacaine plus Dexmedetomidine versus Bupivacaine plus Fentanyl for Caudal Block in Pediatric Infraumbilical Surgery.

Different additives have been used to improve the duration and quality of analgesia of the local anaesthetic used in the single-dose caudal block technique, such as opioids, epinephrine, clonidine, neostigmine, etc. Dexmedetomidine is a potent and a highly selective α2-adrenergic agonist having a sympatholytic, sedative, and analgesic effect and has been described as a safe and effective additive in many anaesthetic and analgesic techniques. Another agent is Fentanyl, a lipophilic opioid, is added frequently to local anaesthetics which least likely to cause respiratory depression when given extradurally, because of its high lipid solubility. It improves and prolongs the analgesia following the addition with bupivacaine for lower abdominal or infraumbilical procedures. The study was aimed to compare the efficacy of bupivacaine with dexmedetomidine versus bupivacaine with fentanyl for caudal block in pediatric infraumbilical surgery. This experimental study was carried out in Mymensingh Medical College Hospital, Bangladesh from 12 May 2019 to 11 November 2019. Total 60 patients, classified by American Society of Anesthesiologists (ASA) physical status category I-II, listed for infraumbilical surgery under caudal block were randomized by card method in two groups of 30 patients each. Anaesthetics were given by using a standardized protocol for induction, maintenance and recovery. Group BD (n=30) patients was given 1 μg/kg dexmedetomidine with 0.5 ml/kg bupivacaine 0.25% and Group BF (n=30) was given 1 μg/kg fentanyl with 0.5 ml/kg bupivacaine 0.25% for caudal epidural analgesia. Mean age of the patients were 6.1±1.7 years and 6.3±1.2 years in BD and BF group respectively. No significant differences were found between groups with respect to age (p=0.721). Male and female ratio was 1.12:1. In group BD 19(63.3%) patients had ASA I and 11(36.7%) ASA II. In group BF 22(73.4%) of patients had ASA I and 8(26.6%) had ASA II. Baseline heart rate was 95.2 and 98.4 beat/min in group BD and BF respectively. After 15 minute heart rate was found 94.4 beat/min in group BD and 90.9 beat/min in group BF. After 30 minute heart rate was 88.7 beat/min in group BD and 85.2 beat/min in group BF. This study showed statistical comparison of postoperative mean RASS scale and CHEOPS at different time interval between three groups. The corresponding mean differences in various groups were comparable and statistically significant (p<0.05). In group BD score was better than BF and the difference of group BD vs. group BF was significant except at base line, 90 min, 120 min (p>0.05). Dexmedetomidine as an adjuvant to bupivacaine is better than fentanyl in infraumbilical surgery has longer sedation and longer postoperative analgesia. Dexmedetomidine potentiates the action of local anaesthetics without increasing the incidence of side-effects compared to fentanyl.