Comparison of the coracoid and retroclavicular approaches for ultrasound-guided infraclavicular brachial plexus block

This prospective randomized study compared the coracoid and retroclavicular approaches to ultrasound-guided infraclavicular brachial plexus block (IBPB) in terms of needle tip and shaft visibility and quality of block. We hypothesized that the retroclavicular approach would increase needle tip and shaft visibility and decrease the number of needle passes compared to the coracoid approach. A total of 100 adult patients who received IBPB block for upper limb surgery were randomized into two groups: a coracoid approach group (group C) and a retroclavicular approach group (group R). In group C, the needle was inserted 2 cm medial and 2 cm inferior to the coracoid process and directed from ventral to dorsal. In group R, the needle insertion point was posterior to the clavicle and the needle was advanced from cephalad to caudal. All ultrasound images were digitally stored for analysis. The primary aim of the present study was to compare needle tip and shaft visibility between the coracoid approach and retroclavicular approach in patients undergoing upper limb surgery. The secondary aim was to investigate differences between the two groups in the number of needle passes, sensory and motor block success rates, surgical success rate, block performance time, block performance-related pain, patient satisfaction, use of supplemental local anesthetic and analgesic, and complications. Needle tip visibility and needle shaft visibility were significantly better in group R (p = 0.040, p = 0.032, respectively). Block performance time and anesthesia-related time were significantly shorter in group R (p = 0.022, p = 0.038, respectively). Number of needle passes was significantly lower in group R (p = 0.044). Paresthesia during block performance was significantly higher in group C (p = 0.045). There were no statistically significant differences between the two groups in terms of sensory or motor block success, surgical success, block-related pain, and patient satisfaction. The retroclavicular approach is associated with better needle tip and shaft visibility, reduced performance time and anesthesia-related time, less paresthesia during block performance, and fewer needle passes than the coracoid approach. Clinicaltrials.gov (no. NCT02673086).