Comparative study of different doses of intrathecal clonidine as an adjuvant to bupivacaine for lower limb surgeries: A prospective observational study

Clinical studies suggested that intrathecal clonidine as an adjuvant to hyperbaric bupivacaine prolongs sensory as well as the motor block of spinal anesthesia, decreases local anesthetic drug requirement, and provides postoperative analgesia.In the present study, we have examined the effects of two distinct clonidine dosages administered intrathecally as an adjuvant to hyperbaric bupivacaine in individuals undergoing elective lower limb operations, to find out the optimal dose among them. Two groups of thirty patients each posted for lower limb surgery were included in this study. Patients in Group A Received inj. bupivacaine (hyperbaric) 0.5% 3ml (15 mg) + inj. clonidine 0.2 ml (30 µg) + normal saline 0.1 ml intrathecally, in Group B patients received inj. bupivacaine (hyperbaric) 0.5% 3ml (15 mg) + inj.clonidine 0.3 ml (45 µg) intrathecally.Throughout spinal anesthesia; both groups were prospectively observed for various parameters. Compared to patients in group A, patients in group B experienced sensory and motor block for longer durations of time. As compared to group A patients, group B patients experienced increased hypotension, bradycardia, and dry mouth; however, overall adverse effects are mild and easily treated. In addition, we observed that group B patients experienced analgesia for a longer duration of time than did Group A patients. Addition of intrathecal clonidine to bupivacaine significantly hastens the onset of sensory and motor block, provides excellent surgical analgesia, prolongs the duration of superior quality postoperative analgesia and reduced postoperative analgesic requirements with relative hemodynamic stability.