Low Dose Bupivacaine (0.25%) with Fentanyl vs Ropivacaine (0.25%) with Fentanyl for Caudal Analgesia in Paediatric Patients: A Randomised Clinical Study

Introduction: Caudal epidural block is one of the most common regional techniques in paediatric anaesthesia for infraumbilical surgeries. Though bupivacaine is widely used because of its long duration, ropivacaine is a newly emerging drug having differential neuraxial blockade with less motor block and reduced cardiovascular and Central Nervous System (CNS) toxicity. To further increase the duration and quality various adjuvants have been added.

Aim: To compare low dose bupivacaine-fentanyl with ropivacaine-fentanyl in terms of haemodynamic stability, duration of analgesia, postoperative pain, level of sedation, and side-effects profile among patients undergoing infraumbilical surgery.

Materials and Methods: A double-blind, randomised clinical study was conducted on 60 children undergoing elective infraumbilical surgery. Patients were randomly divided into two groups of 30 each into Bupivacaine-Fentanyl (BF) group and Ropivacaine-Fentanyl (RF) group, using a simple envelope method. After securing airway, caudal block was given. Group BF received 0.25% bupivacaine 0.5 mL/kg with fentanyl 0.5 mcg/kg and Group RF received 0.25% ropivacaine 0.5 mL/kg with fentanyl 0.5 mcg/kg. Postoperative pain was assessed using the Face, Legs, Activity, Cry, Consolability (FLACC) pain assessment scale, for 12 hours. The haemodynamics, duration of analgesia, rescue analgesia requirement and side-effects (bradycardia, hypotension, respiratory depression, retching, urinary retention, vomiting) were noted and analysed statistically.

Results: The mean duration of analgesia in the BF group was 270±46.60 minutes and in the RF group was 430±68.83 minutes (p-value <0.001). Patients requiring rescue analgesia were 12 in Group BF and 5 in Group RF. Mean FLACC reached ≥4 at 4.5 hours in group BF and at 7 hours in group RF. There was no significant difference in haemodynamics and side-effects profile (bradycardia, hypotension, respiratory depression, retching, urinary retention, vomiting) between the two groups.

Conclusion: Low dose caudal ropivacaine-fentanyl combination is superior to that of caudal bupivacaine-fentanyl with respect to duration and intensity of intraoperative and postoperative analgesia.