Minimal Side-effects and Adequate Analgesia in Spinal Anaesthesia: A Randomised Double Blinded Study Comparing Buprenorphine and Clonidine

Abstract

Introduction: Postoperative patient management includes managing the acute postoperative pain as well as the sideeffects associated with the use of various medications in pain management. Opioids like buprenorphine are excellent in providing analgesia but causes nausea, vomiting among other side-effects. Clonidine is another class of drugs used as an adjuvant but the dose related sympatholytic effect is troublesome to handle. Aim: To evaluate the efficacy buprenorphine (45 μg) and clonidine (22.5 μg) when used in low doses as an adjuvant in spinal anaesthesia and to study the incidence of the most common side-effects. Materials and Methods: The double-blinded randomised clinical study was conducted in the Bangalore Baptist Hospital, Hebbal, Bengaluru, karnataka, India, from January 2014 to October 2014. Hundred patients, aged between 18-55 years, American Society of Anaesthesiologists (ASA) grade I and II, scheduled for lower limb and lower abdominal surgeries were studied. They were divided randomly into two groups i.e, group X and group Y of 50 each. All patients were given 15 mg (3 mL) of 0.5% hyperbaric bupivacaine and along with that the patients in the group X (buprenorphine group) were given 45 μg (0.15 mL) of buprenorphine and the patients in group Y (clonidine group) were given 22.5 μg (0.15 mL) of clonidine. The duration of analgesia, requirement of supplemental analgesics and incidence of sideeffects were noted. Results: The duration of analgesia was found to be longer in the buprenorphine group (448.47±78.08 min) when compared to the clonidine group (311.70±71.92 min). The requirement of supplemental analgesics were, 94% in buprenorphine group required 1-2 doses and 92% in the clonidine group required 3-5 doses of analgesics in the 1st 24 hours, postoperatively. Among the side-effects, 4% of the patients in the buprenorphine group had bradycardia and hypotension, while 6% had nausea and vomiting. In comparison, 18% of patients in the clonidine group had hypotension, nausea (14%), vomiting (12%) and bradycardia (6%). Conclusion: Both buprenorphine and clonidine, in low doses, provide effective postoperative analgesia with minimal sideeffects; while in comparison, buprenorphine has been found to fair better.