Ultrasound-guided Versus Blind Technique in Medial Brachial Cutaneous Nerve and Intercostobrachial Nerve Blocks

The Effectiveness of Ultrasound-guided Technique Compared to Blind Technique in Medial Brachial Cutaneous Nerve Block and Intercostobrachial Nerve Block, in the Axilla

The axillary brachial plexus block is a technique of locoregional anesthesia indicated in the distal upper limb surgery : hand, forearm, the lower third of the arm including the elbow. The anesthesia of the posterior and the medial side of the arm requires a selective block of the medial brachial cutaneous nerve and the intercostobrachial nerve, for example to improve the tolerance of the inflatable tourniquet used by the surgeons. There are two techniques to achieve this block : the blind technique (without ultrasound) and the ultrasound-guided technique. At the moment, there are no studies which compare these two techniques. So, the purpose of this study is to determine the effectiveness of ultrasound-guided technique compared to blind technique in medial brachial cutaneous nerve block and intercostobrachial nerve block, in the axilla.

For purposes of this single-blind monocentric study, 84 patients are randomized into two groups (42 patients for each), upon enrolment into the study.

In the first group, the blind technique is used to perform the medial brachial cutaneous nerve block and the intercostobrachial nerve block : it consists in performing a subcutaneous injection of the local anesthetic at the root of the arm, in the anterior-posterior direction.

In the second group, the ultrasound-guided technique is used to perform the medial brachial cutaneous nerve block and the intercostobrachial nerve block : ultrasounds are used to visualize the anatomical variations, the good position of the needle and the good local anesthetic diffusion.

The aim is to evaluate the effectiveness of ultrasound-guided technique compared to blind technique in medial brachial cutaneous nerve block and intercosto-brachial nerve block, in the axilla

Inclusion Criteria:

• Adult patients ≥ 18 years
• Surgery of the distal upper limb : hand, forearm, lower third of the arm ,including the elbow
• Urgent or planned surgery
• Locoregional anesthesia : axillary brachial plexus block, completed by a medial brachial cutaneous nerve block and an intercostobrachial nerve block
• Local anesthetic used : mepivacaine 10mg/ml
• In the absence of patient objections

Exclusion Criteria:

• Pregnancy
• Adults under guardianship
• Locoregional anesthesia contraindications
• Local anesthetic used : ropivacaine 0,75%