Comparison of Hypobaric Ropivacaine and Hypobaric Bupivacaine in Unilateral Spinal Anesthesia

Objective To compare the efficacy of 0.375% hypobaric ropivacaine and bupivacaine for unilateral lower limb surgery.Methods Sixty patients with ASA grade Ⅰ-Ⅱ were randomly allocated to two groups.Spinal anaesthesia was performed from the L3-4 interspace in all patients keeping the lateral decubitus position with the operative side up.Group B(n=30) received 2 ml of 0.375% hypobaric bupivacaine and group R(n=30) received 2 ml of 0.375% hyperbaric ropivacaine.Patients were kept in the lateral decubitus position for 15 minutes and were then turned to the supine position.The characteristics of spinal block,quality of spinal anaesthesia,adverse effects and recovery times were recorded.Results The onset of motor block were significantly later in group R as compared to group B(P0.05).The duration of motor block were significantly shorter in group R as compared to group B(P0.05).Conclusion For unilateral lower limb surgery,2 ml of 0.375% hypobaric ropivacaine is preferred to bupivacaine because it provides a faster motor recovery.