Feasibility of Forearm Ultrasonography-Guided Nerve Blocks of the Radial, Ulnar, and Median Nerves for Hand Procedures in the Emergency Department

Abstract

We determine the feasibility of forearm ultrasonography-guided nerve blocks of the radial, ulnar, and median nerves, performed by emergency physicians, to provide procedural anesthesia of the hand in the emergency department (ED). This was a prospective study involving a convenience sample of 11 patients presenting to an adult ED with hand pathology requiring a procedural intervention. Adults 18 years and older who presented to the ED during the 3-month study period were eligible. Physicians performing the nerve blocks were attending physicians, ultrasonography fellows, or residents who had participated in a 1-hour training session. The participants underwent ultrasonography-guided nerve blocks in the forearm to provide anesthesia. Any additional anesthesia or analgesia required to perform the procedure in the anesthetized region was recorded. Subjects rated their pain on a 100mm visual analog scale before the nerve block and 15 minutes after the nerve block. The primary outcomes for feasibility were the percentage of cases completed without rescue anesthesia or analgesia and the median reduction in pain on the visual analog scale after the nerve block. Secondary outcomes for feasibility included the median time to completion of the entire nerve block procedure for each subject (from initiation of ultrasonography to completion of the last injection) and the percentage of participants wishing to have the same procedure for similar injuries in the future. Other secondary outcomes included the percentage of participants with complications during the procedure and at 3 months. All procedures (100%) were completed without additional anesthesia or analgesia. The median reduction in visual analog scale score was 5.0 cm (interquartile range 3.0, 8.0; P=.003). The median time to completion of nerve blocks was 9 minutes per patient (interquartile range 6 minutes 30 seconds, 10 minutes 0 seconds), with a median of 2 blocks per patient. Ten of 11 patients (92%) stated they would wish to have the ultrasonography-guided nerve block in the future for similar injuries. There were no immediate complications and no complications reported at 3 months. Attending physicians, fellows, and residents can perform forearm ultrasonography-guided nerve blocks of the radial, ulnar, and median nerves quickly, without additional anesthesia and with high patient satisfaction, after minimal training. Although pilot data are suggestive, randomized controlled trials are needed to determine efficacy and safety. Ultrasonography-guided nerve blocks to provide anesthesia for hand procedures appear to be feasible in the ED.