Medial versus lateral approach in ultrasound-guided costoclavicular brachial plexus block for upper limb surgery: a randomized control trial.

Introduction: Costoclavicular brachial plexus block has become a procedure of choice for surgical anaesthesia or analgesia in upper limb surgery. The technique is not standardised yet, and two approaches are currently employed: the medial and lateral approach. Our study aims to compare the two approaches in terms of performance time and patient-specific clinical outcomes.

Material and methods: The primary outcome assessed was performance time. The secondary outcomes were imaging time, needling time, block onset time, total anaesthesia time, anaesthesia success, and performer difficulty score.

Results: Of 59 patients, 30 patients were randomized to Group M and 29 patients were randomized to Group L. We conducted statistical analysis using a modified intention-to-treat approach. The mean ± SD for performance time (in minutes) was 11.9 ± 3.8 in Group M and 9.4 ± 4.1 in Group L with a difference between means (95% CI) of 2.4 (0.3 to 4.5) ( P < 0.05). The median (interquartile range) needling time of Group M was 9.5 minutes (5-16) vs. 7 (4-19) in Group L ( P = 0.035). Among patients, 40%, 26.67%, 33.3% in Group M had grade 3, 2, 1 performer difficulty whereas 10.3%, 37.9%, 51.7% in Group L had grade 3, 2, 1 performer difficulty, respectively ( P = 0.032). The mean performance time was 9.95 minutes in patients with body mass index (BMI) 25 ( P = 0.0243).

Conclusions: Our study revealed that the medial approach has no significant advantage over the lateral approach with regards to performance time, imaging time, needling time, and performer difficulty. Both performance time and performer difficulty increase with BMI and depth of the cords, with a larger difference in the medial approach.