Comparing efficacy of epidural dexamethasone versus fentanyl on post operative analgesia – a double blinded randomized study

Introduction: Various techniques and drugs have been adopted to prolong postoperative analgesia. Epidural steroids have been used successfully for long time for chronic pain syndrome. The safety of epidural steroids is well established. Based on the above evidences and concepts we used dexamethasone and opiod as adjuvant to local anesthetic agent in our study. Aim and Objective: To compare the efficacy of epidural dexamethasone versus fentanyl on post operative analgesia. Materials and Method: After getting Ethical committee approval and written informed consent the study was conducted in 60adult male patients aged between 25 –45 years belonging to ASA Physical status I and II undergoing elective hernioplasty under epidural anesthesia were randomly allocated into one of the three groups (20 patients per group) by lotting method. Method of blinding: Patients and the person performing the epidural technique was unaware of the epidural drug composition. The drug solution was prepared by an anaesthesiologist assistant in the operating room and was labelled accordingly. Study period: From onset of epidural blockade to onset of postoperative pain with VAS > 5. Group 1: Patients receiving 11 cc of 0.5% bupivacaine plus normal saline 1 cc epidurally. Group 2: Patients receiving 11 cc of 0.5% bupivacaine plus 50 µg fentanyl epidurally. Group 3: Patients receiving 11 cc of 0.5% bupivacaine plus 4 mg preservative free dexamethasone epidurally. All patients received a total volume of 15 ml of study drug including 3 ml of test dose plus 1 ml of adjuvant. All patients were monitored for 24hrs postoperative period for complications, hemodynamics and pain. Results: Group 2 patients with fentanyl as adjuvants showed early onset of anesthesia 5.075 min when compared with their two groups(group 1 -5.3min and group 3 6.252 min) v but group 3 patients with dexamethasone showed prolonged duration 373 min(group 1 -256.05 min and group2- 347.25min). Conclusion: We conclude that epidural dexamethasone resulted in prolonged postoperative analgesia without any side effects like nausea, vomiting, pruritus, sedation except hypotension in few patients. Dexamethasone can be used as adjuvant in single dose epidural techniques with adequate monitoring.