A comparative study of 0.75% ropivacaine and 0.5% bupivacaine for epidural anesthesia in patients undergoing lower abdominal and lower extremity surgeries

Background: Regional anaesthesia has come to occupy an important part in clinical anaesthesiology today. As with other fields, regional anaesthesia too has undergone major developments both in techniques and drug availability. Aim: To study and compare the effect of 0.75% Ropivacaine with 0.5% Bupivacaine for epidural anaesthesia in patients undergoing lower abdominal and lower extremity surgeries with respect to the following factors, Onset and Duration of Sensory Block and Onset and Duration of Motor Block. Materials and Methods: To conduct this study, it was decided to consider a random sample of at least sixty (60) patients of either sex between the age of 20-65 years belonging to the American Society of Anaesthesiologists (ASA) physical status I or II scheduled to undergo elective surgery. The study was conducted to compare 0.75% Ropivacaine and 0.5% Bupivacaine for epidural anaesthesia in lower abdominal and lower extremity surgeries across the following parameters; Time taken for the onset of sensory block T12, Time taken for maximum height of sensory block T6, Time taken for two dermatome segment regression, Time taken for regression up to T12, Time taken for the onset of maximum motor block and Duration of motor block. Results: The onset time for sensory block up to T12 and up to the maximum height of T6 were found to be statistically insignificant; there was no difference in the effect of both the drugs. The two dermatome segment regression and regression up to T12 were statistically significant; it was prolonged in the case of Ropivacaine compared to Bupivacaine. The onset of motor block was statistically significant and was found to be faster in the case of Bupivacaine. The duration of the motor block was also statistically insignificant and it was the same for both the drugs. Conclusion: From these results, this study provides a reasonable ground to conclude that Ropivacaine and Bupivacaine differ in terms of their onset and duration of both sensory and motor block in epidural anaesthesia. Thus Ropivacaine with its higher efficacy, prolonged sensory blockade, lower propensity for motor blockade, proven reduced potential for CNS toxicity and cardiotoxicity, appears to be an important option for regional anaesthesia, management of post-operative pain, labour pain making it the current local anaesthetic drug of choice.