Study of spinal anaesthesia with isobaric levobupivacaine and ropivacaine in elective lower limb orthopaedic surgeries

Introduction and Objectives: Levobupivacaine and Ropivacaine, the two S enantiomers of Bupivacaine can be safer alternatives to racemic bupivacaine due to claims of cardiovascular safety profile. Hence, this study was conducted to assess the clinical efficacy of Levobupivacaine and Ropivacaine for spinal anaesthesia for orthopaedic surgeries of lower limbs. Methods and Materials: For this study, 60 adult ASA class I and II patients admitted for elective lower limb orthopaedic surgeries were randomised to 2 groups of n=30 each after approval from ethical committee and informed written consent. Spinal anaesthesia was given with 3ml Levobupivacaine 0.5% (15 mg) to patients in Group L and with 3ml Ropivacaine 0.5% (15 mg) to patients in Group R. Characteristics of spinal anesthesia in the two subsets like analgesia, motor blockade and hemodynamic parameters were observed and adverse effects, if any, were recorded. Data obtained were compiled and analysed with suitable statistical tests. A p-value of 0.05 was considered significant. Results: Onset of sensory and motor block were significantly faster in Group L (7 and 1.87 min) compared to Group R (9.43 min and 3.10 min). The maximum level of analgesia was attained faster in Group L (12.67 mins) compared to Group R (16.67 mins). The two segment regression time and the duration of analgesia were significantly shorter in Group R (72.63 min, 213.93 min) compared to Group L (103.6 min, 251.33 mins) Higher grade of motor blockade was achieved rapidly in Group L (9.03 mins) when compared to Group R (12.63 min). The mean duration of motor blockade was prolonged in Group L (263.67 mins) whereas recovery from motor blockade was earlier in Group R (151.17 mins). Both the groups had stable hemodynamics and adverse effects were not observed in both the groups. Conclusion: Intrathecal isobaric Levobupivacaine 15mg and Ropivacaine 15mg are effective in lower limb orthopaedic surgeries without significant haemodynamic changes. However, Levobupivacaine produced faster onset, prolonged and higher level of sensory block, prolonged motor blockade compared to Ropivacaine.