A Triple-Masked, Randomized Controlled Trial Comparing Ultrasound-Guided Brachial Plexus and Distal Peripheral Nerve Block Anesthesia for Outpatient Hand Surgery

Abstract

Background. For hand surgery, brachial plexus blocks provide effective anesthesia but produce undesirable numbness. We hypothesized that distal peripheral nerve blocks will better preserve motor function while providing effective anesthesia. Methods. Adult subjects who were scheduled for elective ambulatory hand surgery under regional anesthesia and sedation were recruited and randomly assigned to receive ultrasound-guided supraclavicular brachial plexus block or distal block of the ulnar and median nerves. Each subject received 15 mL of 1.5% mepivacaine at the assigned location with 15 mL of normal saline injected in the alternate block location. The primary outcome (change in baseline grip strength measured by a hydraulic dynamometer) was tested before the block and prior to discharge. Subject satisfaction data were collected the day after surgery. Results. Fourteen subjects were enrolled. Median (interquartile range [IQR]) strength loss in the distal group was 21.4% (14.3, 47.8%), while all subjects in the supraclavicular group lost 100% of their preoperative strength, P = 0.001. Subjects in the distal group reported greater satisfaction with their block procedures on the day after surgery, P = 0.012. Conclusion. Distal nerve blocks better preserve motor function without negatively affecting quality of anesthesia, leading to increased patient satisfaction, when compared to brachial plexus block.

Can We Perform Distal Nerve Block Instead of Brachial Plexus Nerve Block Under Ultrasound Guidance for Hand Surgery?

“…However, we could not record the time of total anesthesia preparation. In some studies, the performance time was shorter in the proximal group than in the distal group, whereas there was no statistically significant difference in the study carried out by Soberon et al [1,5,11]. We consider that the identification of nerves by US before the nerve block procedure shortens the performance time.…”

“…Frederickson et al [9]. did not find a difference in patient satisfaction, whereas Lam et al [1] found a statistically significant difference in their study. The maintenance of motor function is an important advantage of distal nerve blocks because of the need to protect the arm operated on from inadvertent injury [10].…”

“…We selected only radial plus median nerve block to achieve standardization in this study, although there are studies on different kinds of distal nerve block in the literature. Whereas Soberon et al performed radial, ulnar, and median nerve blocks, Lam et al [1] blocked the ulnar and median nerves in their study (5).…”

“…Distal peripheral nerve blocks are applied to supplement an insufficient brachial plexus block (7) or an anesthetic technique for minor hand surgery [1,8]. We have listed our surgical procedures in Table 3.…”

“…Ultrasound (US)-guided regional anesthesia is a common anesthetic technique for patients undergoing hand surgery [1]. The advent of US, as a noninvasive method, allows the nerves and anatomical structures to be viewed directly.…”