Local Anesthesia With Minimal Sedation and Brachial Plexus Block in Hand Surgery

In many hospitals, the widely-accepted benefits of local anesthesia have moved minor hand operations such as carpal tunnel and trigger finger release outside of the main operating room. The proven benefits of local anesthesia include increased efficiency, convenience and patient comfort, reduced costs, lack of pre-operative tests, and decreased operative time. Multiple complex hand operations have been described using lidocaine and epinephrine only, with the patient wide awake during surgery. These include K-wire fixation, flexor tendon repair, tendon transfers, and tendon grafting. For those unfamiliar with this technique, the main concerns are that it is poorly tolerated, does not prevent patient movement, and inadequately controls post-operative pain, which all negatively influence a surgeon's comfort and adoption of this technique. Thus, despite its many advantages, local anesthesia in complex hand surgery is still not widely practiced in North America.

Alternatively, the brachial plexus block is a common method of regional anesthesia used in hand surgery, consisting of anesthetizing the entire upper limb via local anesthesia infiltration of the brachial plexus. This reliable sensorimotor blockade is performed under ultrasound guidance by an anesthesiologist approximately 30 minutes prior to surgery. Although safe and effective to use, its long duration of action, increased need for operating room resources, and unpleasant sensation of a flaccid and insensate upper extremity has prompted research into alternative ultrasound-guided nerve blocks in hand surgery.

Despite prior published data on the use of local anesthesia with epinephrine and brachial plexus blocks in hand surgery, there is a paucity of randomized-controlled, prospective, patient-reported outcome studies comparing these two methods of anesthesia. This study aims to capture patient-reported quality of recovery using a validated, psychometrically tested questionnaire, the Quality-of-Recovery 15. A recent systematic review of the measurement properties of QoR-15 showed good content validity and internal consistency, and concluded that it fulfills requirements for outcome measurement instruments in clinical trials.

Preliminary data was obtained from a pilot study of 11 hand surgery patients who underwent a brachial plexus block and were called 24 hours after surgery to answer the QoR-15 questionnaire. The computed mean QoR score was 118/150 +/- 15, consistent with values reported in the literature. This pilot study allowed for the calculation of a projected sample size for this study, outlined below.

This is a prospective single institution randomized controlled study taking place at the Montreal General Hospital, in Montreal, Canada. The institution is a level I trauma center which performs a minimum of 250 upper extremity surgeries yearly. The study participants are trauma or elective hand surgery patients above 18 years undergoing surgery less than 2 hours in duration distal to the carpal bones.

Patients who consent to the study will be randomized to receive local anesthesia with minimal sedation (intervention group) or a brachial plexus block (control group) using www.random.org, a random number generating website. The local anesthesia in the intervention group will be administered by the operating hand surgeon or a senior resident under the surgeon's direct supervision as a wrist block and/or digital block. The regional blocks in the control group will be performed as an infraclavicular brachial plexus block by a staff anesthesiologist with extensive experience in ultrasound-guided regional anesthesia.

This study is designed as a prospective non-inferiority study using an alpha of 0.05 for statistical significance and a power of 80%. Using QoR-15 values derived from the pilot study with effect size of 0.54, a power analysis was conducted, yielding a sample size of 44 patients per group, for a total of 88 patients. All quantitative outcome parameters will be evaluated for normal distribution and reported as mean +/- SD or median (IQR). Differences between two groups will be evaluated using unpaired Student's T-Test (if parametric) or Mann-Whitney-U test (if non-parametric).

The patients will be called on the first post-operative day, at least 24 hours after the end of their surgery, by a research assistant blinded to the randomization. As a primary outcome measure, the patient will be asked to answer the questions on the QoR-15 without revealing their surgery or method of anesthesia. The dosage of the medications used and the number of times an opioid medication was taken will be recorded. The nonsurgical time for the local anesthesia and brachial plexus groups will also be directly compared. Nonsurgical time is defined as the time elapsed between the completion of surgical closure on one case until the surgical incision on the next case.

The study will be conducted in accord with the Tri-Council Policy Statement: Ethical Conduct for Research Involving Humans (2014) as well as in respect of the requirements set out by the McGill University Health Centre Research Ethics Board.