Neuraxial Ultrasound in Anesthesia and Pain Medicine: Techniques, Evidence, and Future Directions

Abstract Neuraxial ultrasound is a useful tool for scanning neuraxial structure while performing central neuraxial blocks. During a preprocedural scan, it provides anatomical information including locating the midline and interspinous or interlaminar space, identifying the given vertebral/intervertebral level, and determining the depth of the epidural space. This preprocedural scan can help in determining the point of needle insertion and successfully guide subsequent needle insertion. This approach minimizes the number of needle passes, improves procedural success, and thereby enhances patient comfort. In the last decade, various randomized controlled trials (RCTs) on neuraxial ultrasound and few meta-analyses have shown to increase the success rate and reduce the technical difficulty while performing central neuraxial blocks. Findings from the meta-analysis suggest also that neuraxial ultrasound reduces the risk of traumatic procedures and thus may possibly contribute to the safety of central neuraxial blocks. This article will elaborate in-depth of various neuraxial ultrasonographic views for visualization of the neuraxial structure at all the levels of the vertebral column.