Intraoperative and postoperative effects of different doses of bupivacaine: a comparative and prospective study for lower limbs surgeries

Background Central neuraxial block is the gold standard for surgeries below the level of the umbilicus, especially for lower limb operations. Bupivacaine of different concentrations are used for regional blocks and the side effects are attributed to the concentration of the local anaesthetics used.Objective The aim of this study was to prospectively investigate the intraoperative and postoperative effects of different doses of bupivacaine in lower limb surgeries.Methodology A double-blind randomized controlled study was conducted on 120 patients scheduled for emergency lower limb surgeries at Ahmadu Bello University Teaching Hospital from January to December 2017. The patients were randomly grouped into two groups: 1 and 2. The patients in group 1 received 10 mg of 0.5% bupivacaine and 10 μg of fentanyl, whereas those in group 2 received 7.5 mg of 0.5% bupivacaine and 10 μg of fentanyl. Parameters considered included the hemodynamic indices, quality of intraoperative analgesia, onset time of sensory and motor blockade, level of sensory and motor blockade, and duration of the sensory and motor blockade. A P value less than 0.05 was considered statistically significant.Results There was no statistically significant difference (P < 0.05) in the demographic, American Society of Anesthesiologists (ASA) parameters, time of onset of sensory block, and duration of sensory block. There was statistically significant difference in duration of motor blockade, with time of first analgesic request, and more hypotension recorded in group 1 compared to group 2.Conclusion This study has established that 7.5 mg of 0.5% bupivacaine with 10 μg fentanyl has operative analgesia of equal efficacy as 10 mg of 0.5% bupivacaine.