[The trends of ultrasound-guided neuraxial block]

Ultrasound-guided neuraxial block has provided safe and accurate analgesia. Although the classic anatomical landmark technique is still standard for completing epidural or subarachnoid puncture, it is difficult to identify the anatomical structure in some cases such as pregnant women, obese patients and patients with spinal deformity. Preparatory ultrasound scanning enables to identify the midline and determine the point of insertion, which reduces the number of puncture attempts and failure rate of procedure. Moreover, there are reports about the efficacy of ultrasound guidance in children. Usually, neuraxial block for children is performed under general anesthesia which has some risk for nerve injury and inadequate catheterization. Visualization of epidural and subarachnoid space facilitates an appropriate insertion. Additionally, the utility of ultrasound-guided lumbar puncture has also been reported in emergency department. Cerebrospinal puncture is an important procedure for diagnosis of some critical conditions such as subarachnoid hemorrhage and central nervous system infections. Ultrasound imaging contributes to smooth procedure and fewer complications. This review summarizes the basic ultrasound-guided technique for expected difficult neuraxial block patients, presenting recent findings.