A double blind prospective study of effect of intrathecal ropivacaine 0.75% and bupivacaine 0.5% for lower limb orthopedic surgery in young patients

Background: Subarachnoid block is among the most versatile regional block available today. It is a very old and well established anesthetic technique that is simple to perform and has a high success rate and a good safety profile. The aim of the present study was to compare the characteristics of spinal block, adequacy of anaesthesia and side effects using intrathecal ropivacaine 0.75% and bupivacaine 0.5% in young patients undergoing lower limb orthopaedic surgery.Methods: 60 adult patients of either sex (aged 18 to 60 years) were studied, ASA grade I and II were randomly assigned into two anaesthetic groups. Group X: received 3.5 ml of 0.75% isobaric ropivacaine and group Y: received 3.5 ml of 0.5% hyperbaric bupivacaine. After induction, the various parameters of intrathecal block and adequacy of anaesthesia were studied.Results: 0.75% isobaric ropivacaine had late onset of sensory and motor blockade as well as shorter duration of analgesia and anaesthesia with similar quality of block as compare to 0.5% bupivacaine. There was no significant change in the cardiovascular response to subarachnoid block. In present study, no adverse effects were noted in any of the patients in any group.Conclusions: Isobaric ropivacaine at the concentration of 0.75% can be safely used as an alternative to 0.5% hyperbaric bupivacaine as long acting local anaesthetic in intrathecal block