Abstract

Objective: Adjuvants prolong the action of intrathecal local anesthetic agents. They have shown to have significant analgesic effects in the postoperative period much after the regression of the sensory and motor blockade. Our objective of the current study was to compare the hemodynamic profile and adverse effects (nausea, pruritus, sedation and respiratory depression) in two groups of adult patients undergoing infra-umbilical and lower limb surgery under spinal anesthesia using either intrathecal clonidine or intrathecal fentanyl as an adjuvant to intrathecal bupivacaine (0.5% heavy).
 
Materials and Methods: It was a prospective randomized study in which eighty patients posted for lower limb orthopedic surgery were divided into two groups of forty each. Group A – Received intrathecal hyperbaric bupivacaine (2.5 ml) +50 µg clonidine (diluted to 0.5 ml). Group B – Received intrathecal hyperbaric bupivacaine (2.5 ml) + fentanyl 25 µg (diluted to 0.5 ml). Duration of postoperative analgesia, sensory and motor block characteristics, hemodynamic parameters, and side effects were recorded and analyzed.

Results: Both the groups were comparable in demographic data, hemodynamic parameters, but the duration of sensory and motor blockade and duration of analgesia was significantly longer in Clonidine group when compared with the Fentanyl group, with a mild increase in sedation score.
Conclusion: Addition of 50 μg clonidine to intrathecal bupivacaine offers longer duration of postoperative analgesia than 25 μg of fentanyl but with higher sedation. Both the drugs offer similar surgical conditions and prolongs postoperative analgesia (clonidine more than fentanyl), so we suggest fentanyl as better choice when sedation is not desirable and clonidine is recommended where sedation is acceptable.