Comparison of Ultrasound Guided Medial Approach and Lateral Approach of the Costoclavicular Blockage: A Prospective Randomised Study

Introduction:Upper limb surgeries are used on various pathology cases including tendon injuries, carpal tunnel syndrome, tenosynovitis, fractures secondary to trauma, contractures and vascular injuries. In many of such operations local anaesthesia becomes insufficient, and general or regional anaesthesia is required for comfort of the patient and the surgeon. Today, widespread use of nerve stimulators and ultrasound, the availability of post-operative pain management options, applicability of regional anaesthesia where there is risk of complications with general anaesthesia and its applicability along with general anaesthesia for pain management has made regional anaesthesia an attractive solution.The costoclavicular cavity lies in the depth and back of the median of clavicular. It connects to subclavius and clavicular terminus of pectoralis major muscle at the anterior and to the anterior chest wall at the posterior. The cavity is cranially continuous with the supraclavicular fossa and caudally continuous with the medial infraclavicular fossa above the upper border of the pectoralis minor muscle. Unlike the lateral infraclavicular fossa, the cords lie in the costoclavicular cavity in a relatively superficial form in a bundled triangular arrangement. Anatomical layout of cords in the costoclavicular cavity makes this an attractive area for ultrasound imaging and infraclavicular brachial plexus blockage. After placing the linear ultrasound probe on the midclavicular line and even in parallel to the clavicular, the three cords are imaged along with the axillary artery, whereupon local anaesthetic injection can be made with in-plane technique, directing the needle from lateral to medial.

Medial approach to costoclavicular block defined by Nieuwveld involves placement of the linear ultrasound probe on the midclavicular line in parallel with the clavicular, as in the lateral approach, followed by imaging of the three cords alongside the axillary artery, whereupon the needle is directed from the medial to the lateral with the in-plane technique and applying local anaesthetic injection to the midpoint of three cords.

The sample size calculation is done based on the time for establishing total anaesthesia and anaesthesia lead time variables in reference to the study conducted by Prangmalee Leurcharusmee et al. Calculating for 16±5 for lateral approach and 21±7 for medial approach, it is calculated that each group should include 44 patients at 80% power and 95% reliability rate for a meaningful difference at 5 minutes, requiring a total of 88 patients.After obtaining approval of the local ethics board, 88 patients who are considered for emergency or elective superior extremity surgery, in ASA I-IV group, in 18 to 75 age group, who do not have any known serious illness and who consent to participate will be included in the study.

Material and Method:Patients in ASA IV group and above, patients taking anticoagulant/antiaggregate treatments, patients with nervous disorders, patients with infections or open wounds at the operation area and patients with allergies against any drug to be used in the study will be excluded from the study.

Patients participating in the study will be randomly divided into 2 separate groups. These groups will be referred to as the Group M (Medial approach group) and Group L (Lateral approach group).