Evidence Base for the Use of Ultrasound for Upper Extremity Blocks

Abstract

This article reviews and summarizes randomized, controlled studies that have assessed ultrasound (US) guidance for brachial plexus blocks in comparison with other nerve localization methods as well as those that have compared different US-guided brachial plexus block techniques. Both PubMed and EMBASE databases were searched using the MeSH terms anesthetic technique, brachial plexus, and ultrasound. Studies were included if they had randomized allocation comparing US with another conventional nerve localization technique or if they compared 2 different US-guided techniques, such as single versus multiple injections. Each study was classified as a categorical outcome as being supportive, unclear, or negative for the use of US. These were compared with χ analysis with the null hypothesis that US provides no benefit for brachial plexus blocks. Forty-seven studies met the inclusion criteria, and 29 compared US guidance to landmark or peripheral nerve stimulation techniques. Our analysis of the literature supports the use of US over other nerve localization techniques as being beneficial for several block performance outcomes including block performance time, reducing the number of needle passes and the incidence of vascular puncture, shortening sensory block onset time, and improving block success.

The Second American Society of Regional Anesthesia and Pain Medicine Evidence-Based Medicine Assessment of Ultrasound-Guided Regional Anesthesia

“…3 Although this latter statement is not based on meta-analysis, it is consistent with Cochrane analysis conclusions. 16 Of those 14 studies that reported sensory block onset at a predetermined time point, US was superior to the comparator (ranging from 75% vs 47% on the low side to 100% vs 77% on the high side, respectively).…”

“…The 3 negative studies used combination US-PNS guidance, which has been reported to increase procedure time, but not to improve block characteristics. 3 Six of 7 studies found no difference in block duration.…”

“…Specific methodologies for the various components of this project are detailed in the accompanying individual articles. [2][3][4][5][6][7][8][9] In brief, putative evidence was gathered using a variety of standard electronic search engines to identify relevant literature, concentrating on the period from 2009 through spring 2015. The specific search engines used, language limitations, and MeSH (medical subject headings) are described in the individual articles.…”

“…[2][3][4][5][6][7][8][9] Clinicians are encouraged to read these supporting articles for a more complete understanding of the evidence basis for UGRA.…”

Regional anesthesia in pain management

“…Multiple recently published systematic reviews found ultrasound guidance to improve the performance of the blocks and different patient outcomes [11][12][13][14]. Importantly, the expectation that direct visualization of the neural structures would reduce the incidence of neurologic complications has not been confirmed, but ultrasound guidance has been found to reduce the risk of local anesthetic systemic toxicity and possibly pneumothorax [15 & ].…”