Intrathecal Buprenorphine, Clonidine and Fentanyl as Adjuvants To 0.5% Hyperbaric Bupivacaine In Lower Abdominal Surgeries: A Prospective, Randomized And Comparative Study

Background: Among all the spinal adjuvants, clonidine, an alpha-2 agonist has the ability to alleviate both the somatic and visceral pain and is more potent at spinal site, favoring its neuraxial administration. Objective: This study was done to compare the onset and duration of sensory and motor blocks, duration of analgesia, haemodynamic and adverse effects of Clonidine, buprenorhine and fentanyl used intrathecally with hyperbaric 0.5% bupuvacaine. Settings & Design: This prospective, randomized and comparative study included 90 ASA class 1 & 2 patients undergoing lower abdominal surgeries under spinal anesthesia after approval from hospital ethics committee with written informed consent of patients. Materials And Methods: Patients were randomly allocated into three groups (n=30) and received 50μg of clonidine, 25μg of fentanyl and 75μg of buprenorphine respectively in group BC,BF and BB as adjuvants to 15mg of 0.5% hyperbaric bupivacaine (3.0ml). The onset time and duration of sensory and motor block, duration of analgesia, haemodynamic changes and side effects were recorded. Results: The onset time of motor block and durations of sensory, motor blockade and analgesia were prolonged in-group BC as compared to group BF and BB (P<.001). There was no significant difference in the onset time of sensory block in three groups (P>.05). Group BC had lower heart rate and mean blood pressure and higher sedation score. Conclusion: Intrathecal Clonidine in a dose of 50μg is an effective adjuvant to local anesthetics in neuraxial blocks despite mild sedation and haemodynamic variations.