Pre-Procedural Lumbar Neuraxial Ultrasound—A Systematic Review of Randomized Controlled Trials and Meta-Analysis

Abstract

A pre-procedural ultrasound of the lumbar spine is frequently used to facilitate neuraxial procedures. The aim of this review is to examine the evidence sustaining the utilization of pre-procedural neuraxial ultrasound compared to conventional methods. We perform a systematic review of randomized controlled trials with meta-analyses. We search the electronic databases Medline, Cochrane Central, Science Direct and Scopus up to 1 June 2019. We include trials comparing a pre-procedural lumbar spine ultrasound to a non-ultrasound-assisted method. The primary endpoints are technical failure rate, first-attempt success rate, number of needle redirections and procedure time. We retrieve 32 trials (3439 patients) comparing pre-procedural lumbar ultrasounds to palpations for neuraxial procedures in various clinical settings. Pre-procedural ultrasounds decrease the overall risk of technical failure (Risk Ratio (RR) 0.69 (99% CI, 0.43 to 1.10), p = 0.04) but not in obese and difficult spinal patients (RR 0.53, p = 0.06) and increase the first-attempt success rate (RR 1.5 (99% CI, 1.22 to 1.86), p < 0.0001, NNT = 5). In difficult spines and obese patients, the RR is 1.84 (99% CI, 1.44 to 2.3; p < 0.0001, NNT = 3). The number of needle redirections is lower with pre-procedural ultrasounds (SMD = −0.55 (99% CI, −0.81 to −0.29), p < 0.0001), as is the case in difficult spines and obese patients (SMD = −0.85 (99% CI, −1.08 to −0.61), p < 0.0001). No differences are observed in procedural times. Ιn conclusion, a pre-procedural ultrasound provides significant benefit in terms of technical failure, number of needle redirections and first attempt-success rate. Τhe effect of pre-procedural ultrasound scanning of the lumbar spine is more significant in a subgroup analysis of difficult spines and obese patients.

Ultrasound-Assisted Spinal Anesthesia in a Patient with a Preexisting Lumbar Interspinous Spacer: A Case Report

“…Previous case reports of successful neuraxial anesthesia in obstetrical patients with intrathecal baclofen pumps or spinal cord stimulators have been documented. 4,5 In 4 out of 5 patients described in case reports, lumbar neuraxial ultrasonography was used preoperatively to aid in placement of spinal blockade in patients with preexisting intrathecal baclofen pumps and spinal cord stimulators. 4,5 However, the approaches to neuraxial ultrasound examinations were not well described in the case reports, and ultrasound images were unavailable for review.…”

“…4,5 In 4 out of 5 patients described in case reports, lumbar neuraxial ultrasonography was used preoperatively to aid in placement of spinal blockade in patients with preexisting intrathecal baclofen pumps and spinal cord stimulators. 4,5 However, the approaches to neuraxial ultrasound examinations were not well described in the case reports, and ultrasound images were unavailable for review. There are no existing case reports of patients with indwelling spinal hardware that also describe the methodology or include images of lumbar neuraxial ultrasonography.…”

“…Successful neuraxial anesthesia has been described in obstetrical patients with other implantable devices including intrathecal baclofen pumps or spinal cord stimulators. [3][4][5] However, there are no current reports of ultrasound-assisted performance of spinal anesthetics to avoid an indwelling interspinous spacer device.…”

Ultrasonographic images of spina bifida before obstetric anesthesia: a case series

“…Performing neuraxial anesthesia in obstetric patients with spina bifida can be challenging because of increased technical difficulty and the risk of neurologic complications. Recent systematic reviews have indicated that the lumbar US can provide anatomic information indicating the depth of the epidural space, the identity of a given intervertebral level, the location of the midline, and interspinous or interlaminar spaces [ 3 , 4 ]. In addition, lumbar US can help to improve clinical outcomes of neuraxial anesthesia [ 5 – 7 ].…”

“…Preprocedural imaging of the lumbar spine by computed tomography (CT) or magnetic resonance imaging (MRI) can be crucial for determining the feasibility of neuraxial anesthesia, but there are risks [ 3 , 4 ], and these modalities can be expensive. Lumbar ultrasonography (US) can be used easily, safely, and consistently to facilitate neuraxial procedures for pregnant women [ 3 , 4 ]. We present four cases of pregnant women with spina bifida who underwent lumbar US before obstetric analgesia or anesthesia.…”