Experience of using local anesthetic combinations

Background. The general toxic effects of local anesthetics on vital organs are the most severe side effects of regional blockades. The purpose was to study the effectiveness and safety of combined solutions of local anesthetics in the brachial plexus block. Materials and methods. Forty-nine patients were divided into 2 study groups. The first group (controls) consisted of 24 individuals who received a solution of 0.5% bupivacaine 36 ml (180 mg) with adrenaline 1 : 200,000 as an adjuvant to block the brachial plexus. The second group (main) consisted of 25 patients, who were treated with a mixture of 2% lidocaine 12 ml (240 mg) and 0.5% bupivacaine 12 ml (60 mg) diluted with a solution of 0.9% NaCl 12 ml and adrenaline 1 : 200,000 as an adjuvant. Results. In the first group (bupivacaine), the onset time of sensory block averaged 11.3 ± 4.3 minutes, motor block — 21.0 ± 7.8 minutes. The motor block duration was 894 ± 237 minutes. In the second group (mixture), the onset time of sensory block averaged 8.0 ± 3.6 minutes, motor block — 14.0 ± 6.2 minutes, which was significantly less than in the first group. The duration of the motor block was 539 ± 186 minutes. The longest postoperative analgesia was registered in the bupivacaine group — 984 ± 263 minutes. The duration of postoperative analgesia in the main group was slightly shorter — 612 ± 210 minutes. Conclusions. The proposed combination of local anesthetics bupivacaine and lidocaine allows reducing the bupivacaine dose by three times, which decreases the toxic complications of conduction anesthesia. The clinical use of the proposed drug combination reduces the duration of the latent period and provides long-term postoperative analgesia.