Ultrasound Imaging Compared to Manual Palpation to Determine Lumbar Anatomy for Neuraxial Anesthesia

Background: Neuraxial anesthesia represents the final set of procedures used by nurse anesthetists that are performed in a blind fashion. However, the use of ultrasound guidance is changing the way these procedures have been performed.

Purpose: The purpose of this study is to explore differences in manual palpation versus ultrasound imaging in identifying vertebral anatomy and the duration of time needed for Student Registered Nurse Anesthetists (SRNAs).

Methods: Manual palpation and ultrasound imaging were compared on two Standardized Patients (SP’s) in the sitting and lateral positions to determine the accuracy and time needed to identify the L3-L4 intervertebral space by SRNAs.

Results: Results of a chi- square analysis indicated that SRNAs identified the L3-L4 intervertebral space more accurately utilizing ultrasound imaging compared to manual palpation in the sitting (SP 1: p=0.0087/ SP 2: p=0.0228) and lateral positions (SP 1: p=0.0003/ SP 2: p=0.0196). A Wilcoxon signed rank analysis indicated that SRNAs took significantly less time determining L3-L4 interspace with manual palpation compared to ultrasound imaging in both the sitting and lateral positions.

Conclusion: Although the duration of the procedure was significantly longer with ultrasound imaging, the accuracy of vertebral identification was much more precise.