A Prospective Cohort Study to Evaluate Needle Passes Using a Portable Ultrasound Device versus Traditional Landmark Approach for Epidural Anesthesia in a Busy Obstetric Tertiary Care Center

Abstract

Despite its many cited benefits, ultrasound guidance for neuraxial procedures is not widespread in anesthesiology. Some cited limitations include device cost and accessibility. We test the hypothesis that a handheld and relatively inexpensive ultrasound can improve neuraxial proficiency (e.g., decreased needle manipulations and block time). This prospective study compared the number of needle passes, redirections, and procedural time between epidural placed with a handheld ultrasound versus landmarks. Needle passes and attempts were defined as the number of times the Tuhoy needle was redirected, and the times skin was punctured (re-insertion). Procedural time was defined as the time from local anesthetic infiltration until loss of resistance was obtained. The impact of level of training and accuracy of the device were also analyzed. 302 patients receiving labor epidural were included in the study. No difference in body mass index (BMI) nor distribution of level of training was noted between the groups. Regression analysis adjusted for BMI demonstrated a decrease in needle passes (-1.75 (95% CI -2.62, -0.89), p < 0.001), needle attempts (-0.51 (95% CI -0.97, -0.04), p = 0.032) and procedural time (-154.67s 95% CI -303.49s, -5.85s), p = 0.042) when a handheld ultrasound was utilized. The mean (95% Confidence interval) difference between needle depth and ultrasound depth was 0.39 cm (0.32, 0.46), p < 0.001. The use of a handheld device resulted in statistically significant decrease of needle manipulations and block time. More research is needed to evaluate the impact of and increase in accessibility of ultrasound technology.