Introduction: Infraclavicular brachial plexus can be blocked by various approaches like classical infraclavicular(CIB), retroclavicular (RCB), parasagittal and pericoracoid. In our study we compared novel RCB approach with CIB approach using dual guidance of ultrasound and peripheral nerve locator.

Methodology: In this prospective, randomised trial, 60 patients were randomly allocated in to two groups CIB (n=30) and RCB (n=30). In the CIB approach, the needle is inserted 2 cm medial and 2 cm inferior to the coracoid process and directed from ventral to dorsal. In RCB approach, the needle insertion point was found  by palpating the supraclavicular fossa, just medial to the shoulder at a point sufficiently posterior to the clavicle and the needle was advanced from cephalad to caudal and block was given with 0.5% ropivacaine injection in the both groups. The primary aim of our study was to compare needle visualization and needling time and secondary outcomes studied were clinical success  rate of block, onset and duration of sensory block and motor block, and patient satisfaction between CIB and RCB groups.

Results: Needle visibility score in RCB was 4.8276 and in CIB 3.0714 which was significantly better in retroclavicular group (p=0.0453) and needling time in RCB was 2.8 mins and in CIB 4.67 which was lesser when compared to classical approach group (p=0.030). There were no statistically significant differences between the two groups in terms of sensory or motor block success, surgical success, patient satisfaction and complication rate.

Conclusion: The flat needle angle, needle visibility, and needling time was better in RCB in comparison with CIB. Hence we conclude that RCB can be considered as a better alternative to CIB approach. Further study in a larger patient population is needed to evaluate if utilizing the retroclavicular approach results in improved efficacy, increased safety, and more rapid acquisition of skill for novice regional anaesthetists.