Ultrasonography and stimulating perineural catheters for nerve blocks: a review of the evidence

Abstract

Purpose: This narrative review summarizes the evidence derived from randomized controlled trials (RCTs) offering blinded assessment and sample size justification, in order to determine the benefits associated with adjunctive ultrasonography (US) and stimulating perineural catheters for nerve blocks. Source:The literature search for this review was conducted during the second week of December 2007 using the MEDLINE (January 1950 to November 2007 and EMBASE (January 1980 to November 2007) databases. For US-guided peripheral and neuraxial blocks, the following medical subject heading (MeSH) terms were searched: "nerve block", "epidural anesthesia", "epidural analgesia", "epidural injection", "epidural space", "spinal anesthesia", and "spinal injection", the results were combined with "ultrasonography" (MeSH term) and "ultrasound" (key word). For stimulating perineural catheters, the following MeSH terms were cross referenced with the MeSH term, "nerve block": "peripheral catheterization", "indwelling catheterization", "catheterization", and keywords, "nerve catheter" and "continuous". Subsequently, the result of this search was combined to "stimulating" (key word). Fifteen RCTs, offering blinded assessment and sample size justification, were retained for analysis.Principal findings: For axillary blocks, US guidance yields a higher success rate than a double-injection, transarterial and a triple-injection, neurostimulation-guided technique. Compared to a quadruple-stimulation technique, no major differences can be found. The addition of nerve stimulation to US guidance offers no clear benefits for axillary blocks. For femoral blocks, compared to neurostimulation, echoguidance is associated with a local anesthetic (LA) sparing effect (up to 42%). In children, US guidance yields a LA sparing effect and a longer duration of action for lower extremity nerve blocks.Compared to their blind counterparts, stimulating catheters seem to offer limited clinical benefits. Despite providing a sparing effect on LA and opioid consumption, stimulating catheters are not associated with a decrease in side effects or analgesiarelated expenditures. Conclusions Sources : La recherche de littérature pour cet article de synthèse a été menée la deuxième semaine de décembre 2007 dans les bases de données MEDLINE (janvier 1950 à novembre 2007) et EMBASE (janvier 1980 à novembre 2007). Pour les blocs périphériques et neuraxiaux échoguidés, les termes MeSH suivants ont été recherchés : « nerve block », « epidural anesthesia », « epidural analgesia », « epidural injection », « epidural space », « spinal anesthesia » et « spinal injection », et ont été associés à « ultrasonography »

The Effect of Stimulating Versus Nonstimulating Catheter Techniques for Continuous Regional Anesthesia

“…A first overview in this field was published in 2008. 19 The authors summarized 8 trials and thoroughly described each single trial, but they did not attempt to pool the results. Since this first review, 3 more trials have been published.…”

Incidental detection of bowel herniation with ultrasonography and fluoroscopy during a caudal block

“…9 Increasingly, the use of ultrasonography is starting to extend to the field of chronic pain management. Although fluoroscopy has been recommended traditionally for caudal blocks, 10,11 a recent case series has reported a 100% success rate when ultrasonography was used to guide needle placement into the caudal canal.…”

Femoral nerve catheter-induced neuralgia

“…However, the threading of catheters for postoperative pain control relies on a blind technique, with inherent uncertainties that may translate into rare but significant complications. While ultrasound-guided techniques are advantageous for upper extremity nerve blocks [7], their use in preventing catheter-related complications remains uncertain. Image quality, particularly of the femoral region, is often limited and real-time visualization of catheter insertion is frequently not possible.…”