[Ultrasound-guided block at the antecubital fossa for carpal tunnel syndrome surgery]

Abstract

Introduction: There are various anaesthetic techniques for ambulatory surgery of carpal tunnel release. The ultrasound-guided nerve blocks offer advantages compared to other techniques. The purpose of this study was to evaluate the efficacy using ultrasound-guided block at the antecubital fossa, as well as to evaluate complications, patient satisfaction and surgeon satisfaction with the block.

Materials and methods: Prospective observational study with 32 elective patients for carpal tunnel release in a one-day case unit. An ultrasound-guided block with mepivacaine 1% was performed at the antecubital fossa, aiming for the median, ulnar and the lateral and medial cutaneous nerves of the forearm. The measurements of the anteroposterior and laterolateral diameters of the median and ulnar nerves were recorded, before and after injection. Motor and sensory levels were evaluated for the median and ulnar nerves at 5 and 30 min post injection, and compared with the contralateral hand. Pain from the surgical incision time and recovery were recorded, together with complications, and patient and surgeon satisfaction with the block.

Results: The antecubital fossa ultrasound-guided block was successful in 93.7% of the patients. No patients needed rescue analgesia in recovery and no complications were recorded. Patient satisfaction was 93.7% and surgeon satisfaction was 97%.

Conclusions: A selective block of the medial, ulnar and medial and lateral cutaneous nerves of the forearm are effective and satisfactory anaesthetic techniques for carpal tunnel release in a one-day case unit. It allows early mobilization, minimises risks and amount of local anaesthetic used.