Comparison of the efficacy of different concentrations and volumes of levobupivacaine in axillary brachial plexus blockade.

ABSTRACT

BACKGROUND: The aim of this study was to compare the effect of the same dosage but different concentrations and volumes of levobupivacaine used for axillary block on the onset and intensity of the block. METHODS: Sixty-nine patients were randomly allocated into three groups. The patients in Group 5, Group 7.5 and Group 3.75 were administered 45 mL of levobupivacaine (5 mg/mL), 30 mL of levobupivacaine (7.5 mg/mL) and 30 mL of levobupivacaine (7.5 mg/mL) mixed with 30 mL of 0.9% NaCl solution, respectively. The onset and intensity of sensory and motor blocks distributed through 4 nerves, duration of analgesia, and total analgesic consumption within 24 hr were recorded. RESULTS: Onset of sensory block on median and radial nerves in Group 3.75 was found to be significantly longer compared to Group 5 and Group 7.5 (P<0.05). Onset of motor block on radial nerves in cases in Group 3.75 was significantly longer compared to those in Group 7.5 (P<0.01). In Group 3.75 the intensity of sensorial blockade at the median ulnar and radial nerves and the intensity of motor blockade at the radial and musculocutaneous nerves were significantly lower than in the other two groups. The duration of analgesia in the patients of Group 5 was significantly shorter compared to those in Groups 7.5 and 3.75 (P<0.01). CONCLUSION: Decreasing the concentration and increasing the volume of levobupivacaine without changing its dosage prolongs the duration of analgesia, although it delays the onset and decreases the intensity of sensory and motor block in axillary block.