A Comparative Study of Epidural Butorphanol and Epidural Fentanyl for the Relief of Post - Operative Pain in Lower Abdominal and Lower Limb Surgeries

BACKGROUND: Epidural anaesthesia is used extensively for both intra-operative and post-operative analgesia.This prospective randomized study was conducted using opioids epidurally for post-operative analgesia.Fentanyl is a pure opioid agonist.Butorphanol tartarate which is an agonist antagonist opioid is considered safer than pure opioid agonist.Hence, we compared epidural 4mg butorphanol and epidural 100 µg fentanyl for the relief of post-operative pain.AIMS AND OBJECTIVES: To compare the onset, duration, quality of analgesia, hemodynamic effects and side effects between the 2 study drugs.MATERIALS AND METHODS: 60 patients of either sex posted for elective lower abdominal and lower limb surgeries were randomly divided into 2 groups of 30 each.Group A received butorphanol 4mg epidurally.Group B received fentanyl 100 µg epidurally.All surgeries were done under lumbar epidural anaesthesia with catheter in situ.Post-operatively when patients complained of pain, intensity of pain was assessed using visual analogue scale [VAS].When the VAS score was > 5, Group A received butorphanol 4mg diluted to 10 ml with NS or Group B received 100 µg fentanyl epidurally diluted to 10 ml with NS.Onset, duration, quality of analgesia, hemodynamic effects and incidence of side effects were compared between the two groups and treated accordingly.RESULTS: Demographic profile was comparable in both groups.Mean time of onset of analgesia was rapid (3.22 ±0.9 (S.D) min) in group B compared to group A (6.38± 1.26 (S.D) min).Duration of analgesia was longer in group A (344.00 ±63.39 min) compared to group B (227±38.12 min).Quality of analgesia was better with group A compared to group B. There was no significant difference in hemodynamic parameters in both groups.Sedation was the main side effect in group A. Incidence of pruritis, vomiting, hypotension and respiratory depression was more in group B. CONCLUSION: Epidural Butorphanol though has a delayed onset of analgesia has a longer duration and better quality of analgesia than fentanyl with paucity of clinically significant side effects with both groups.