Comparison of 0.5% ropivacaine and 0.5% levobupivacaine for infraclavicular brachial plexus block.

A prospective randomized double-blind study was conducted which involved, 60 ASA 1-2, aged 18-65 years patients, who had elective or emergency orthopaedic surgeries of the upper limbs. They were randomly divided into two groups: Group I received 30 mls of 0.5% ropivacaine; and Group II received 0.5% levobupivacaine for infraclavicular brachial plexus block based on the coracoid approach. The onset time required for sensory block of all required dermatomes (C5-T1) and the onset time of motor block were documented. Based on the Visual Analogue Score, pain scores were recorded every 30 minutes during surgery and at the 6th hour. The mean onset time (SD) for sensory block with ropivacaine was 13.5 +/- 2.9 minutes compared to levobupivacaine at 11.1 +/- 2.6 minutes (p = 0.003). The onset time for motor block was 19.0 +/- 2.7 minutes in Group I compared to 17.1 +/- 2.6 minutes (p = 0.013) in Group II. Patients in both groups experienced both mild to moderate pain at the 6th hour. In conclusion, there were statistically significant differences in the onset-time for sensory and motor block. However, there was no statistically significant difference in terms of effectiveness of analgesia at the 6th hour. Although the clinical advantage of levobupivacine is not substantial, its safety profile becomes a major consideration in the choice of local anaesthetic for brachial plexus block where a large volume is required for an effective result.