Carpal Tunnel and Hand Surgery
Carpal tunnel release is typically an ambulatory surgical procedure. It can be performed under local anesthesia, regional anesthesia or brief general anesthetic. In our institution, we perform a large volume of hand surgeries and on a typical day, we may treat as many as 10-20 patients. Although intraoperative local anesthesia by the surgeon can be used, in a large volume outpatient center, such as ours at NYSORA EUROPE, at CREER Center, ZOL, Genk – this would negatively impact the time-efficiency and the operating room utilization. While a proximal brachial plexus block can be indicated (e.g. axillary, infraclavicular, supraclavicular), this results in unnecessary upper extremity immobility for the duration of the block.
At NYSORA, we routinely use distal peripheral nerve blocks (“wrist block”) for all patients having carpal tunnel release, digital tendon repair, and Dupuytren’s contracture surgery. The “wrist block” consists of a mid-forearm level block of the median and ulnar nerves, followed by a subcutaneous infiltration of the local anesthetic at the wrist crease for any remaining cutaneous branches of the musculocutaneous, radial or ulnar nerves. Under ultrasound guidance, the median and ulnar nerves are identified between the superficial and deep flexors of the wrist and fingers. A 25-gauge needle is then inserted in-plane or out-of-plane to inject 3-5 mL of lidocaine 2% into the connective tissue layer containing the nerves. The anesthesia onset is typically within 10 minutes.
Application of a forearm or arm tourniquet is well tolerated for the duration of the surgery, typically 20 minutes or so. As per protocol, we administer premedication for patients comfort with 1-2 mg of midazolam and 5 mg of Ketamine-S, diminishing the need for additional intraoperative sedation or analgesia for the tourniquet. We chose to use this premedication combination as it does not result in respiratory depression and Ketamine-S has less psychotropic effects than its D-isomer.