Effects of addition of different doses of clonidine to intrathecal ropivacaine in lower limb and subumbilical surgeries

Abstract

Aim and Objectives: The present study was undertaken to compare the quality of subarachnoid block and vital parameter changes by addition of different doses of clonidine to intrathecal 0.5% isobaric ropivacaine in sub umbilical surgeries. Methods: The study enrolling 135 patients of either sex (age 20-50 years), ASA grade I and II were randomly allocated into three groups of forty five each. Group I received 15 mcg clonidine + 3.2 ml of 0.5% ropivacaine + 0.2 ml normal saline, group II received 30 mcg clonidine + 3.2 ml of 0.5% ropivacaine + 0.1 ml normal saline and group III received 45 mcg clonidine + 3.2 ml of 0.5% ropivacaine. Characteristics of spinal block, vital parameter changes and level of sedation were recorded. Results: We found no significant effect on onset and quality of sensory and motor block by using different doses of clonidine. Group II and group III had prolonged duration of sensory and motor block as compared to group I. There were no significant differences in maximum level and time to reach maximum level of sensory block in all three groups. Time for two segment regression was significantly prolonged in group II and group III as compared to group I. The incidence of hypotension, bradycardia and level of sedation score was higher in group III as compared to group I and II. Conclusion: addition of 30 mcg of clonidine to intrathecal ropivacaine is safe and likely to be as effective as higher doses in prolonging duration of sensory and motor block and having minimum side effects and hence seems to be optimum.