COMPARATIVE STUDY ON ONSET AND BLOCK QUALITY FOLLOWING SINGLE VS MULTIPLE INJECTION TECHNIQUES IN AXILLARY BRACHIAL PLEXUS BLOCK

Abstract

Background: The axillary brachial plexus block is a well-established regional anesthesia technique for forearm and hand surgeries. Despite its reliability, the optimal injection strategy remains controversial. Single- and multiple-injection techniques are commonly used, yet their comparative effectiveness in terms of onset time, block quality, duration of anesthesia, and safety is still debated. This randomized controlled trial aimed to compare these two approaches to determine which provides superior clinical outcomes. Materials and Methods: Seventy-two adult patients (ASA physical status I–III) scheduled for elective forearm or hand surgery were enrolled and randomly allocated into two equal groups: Group S (single-injection technique) and Group M (multiple-injection technique). All blocks were performed using nerve-stimulation guidance with standardized doses of local anesthetic. Hemodynamic parameters were monitored, and the onset times of sensory and motor block were recorded. Block duration, time to first rescue analgesia, block quality, patient satisfaction, and complications were assessed. Data were analyzed using the independent t-test and chi-square test, with a p value < 0.05 considered statistically significant. Results: Demographic characteristics and baseline hemodynamic variables were comparable between groups (p > 0.05). Group M demonstrated a significantly faster onset of sensory block (10.5 ± 2.2 min vs. 12.0 ± 2.4 min; p = 0.004) and motor block (15.8 ± 3.0 min vs. 18.1 ± 3.6 min; p = 0.006). The duration of sensory and motor blockade, as well as the time to first rescue analgesia, was significantly longer in the multiple-injection group (p < 0.01). Excellent block quality and higher patient satisfaction were more frequent in Group M. Complication rates were low and comparable between groups. Conclusion: The multiple-injection axillary brachial plexus block provides faster onset, superior block quality, longer duration of anesthesia, and higher patient satisfaction without increasing complications, making it a clinically preferable technique for upper-limb surgeries.