A Comparative Study of Clonidine versus Dexmedetomidine as an Adjunct to Hyperbaric Bupivacaine in Spinal Anesthesia for Orthopaedic Lower Limb Surgeries

Spinal Anesthesia for Orthopaedic Lower Limb Surgeries

Abstract

Background: To compare clonidine versus dexmedetomidine as an adjunct to hyperbaric bupivacaine in spinal anesthesia in lower limb surg- eries. Subjects & Methods: Ninety patients belonging to physical status American Society of Anesthesiologists (ASA) Classes I and II between 18- 60 years age group posted for limb surgeries of both genders were randomly divided into 2 groups. Group I were given 3.5 ml volume of injection bupivacaine 0.5% hyperbaric and 0.5 ml normal saline. Group II patients were given 3.5 ml volume of injection bupivacaine 0.5% hyperbaric and 0.5 ml of injection clonidine (30 g) and group III patients were prescribed 3.5 ml volume of injection bupivacaine 0.5% hyperbaric and 0.5 ml of injection dexmedetomidine (5 g). Parameters such as sensory onset, motor onset, duration of motor blockade, time for rescue analgesia, VAS and adverse effects were recorded in both groups. Results: Common adverse events such as nausea in 3 in group I,  1 in group 1 and 2 in group II, bradycardia 2 in group I, 1 in both group II and III, hypotension 2 in group I and group II and 1 in group III and shivering 1 in group I. Sensory onset duration was 2.9 minutes in group I, 1.5 minutes in group II and 1.3 minutes in group III, motor onset duration was 4.1 minutes in group I, 1.7 minutes in group II and 1.2 minutes in group III, duration of motor blockade was 168.2 minutes in group I, 281.4 minutes in group II and 304.2 minutes in group III, time for rescue analgesia was 168.5 minutes in group I, 345.7 minutes in group II and 367.2 minutes in group III and VAS was 6.0 minutes in group I, 5.0 minutes in group II and 4.8 minutes in group III. A significant difference was found in all parameters (P< 0.05). Conclusion: ?2-agonists with hyperbaric bupivacaine intrathecally have a faster onset of both motor and sensory block, prolonged duration of block and better post operative analgesia