Usefulness and accuracy of a handheld ultrasound device for epidurssal landmark and depth assessment by anesthesiology residents

Abstract

Purpose

The aim of this study was to assess the usefulness and accuracy of a handheld ultrasound device (Accuro, Rivanna Medical, Charlottesville, VA, USA) for epidural landmark and depth assessment when epidural anesthesia is performed by residents.

Methods

Patients scheduled to receive epidural anesthesia were randomly assigned to the Accuro group (group A) or control group (group C). In group A, the depth to the epidural space and the appropriate place for epidural insertion according to Accuro was recorded. In group C, epidural anesthesia was performed using a conventional method. The following were recorded and compared between the groups: time from puncture of the Tuohy needle to loss of resistance, number of Tuohy needle redirects, and epidural-related complications. In group A, depth to the epidural space estimated by Accuro (Accuro Depth) and the actual depth measured with a marker on the needle (Needle Depth) were recorded and compared.

Results

Sixty patients were enrolled during the study period. There was no significant difference between the groups regarding the median or range of time required to locate the epidural space.

The number of Tuohy needle redirects was 0 (0–3) in group A and 1.5 (0–7) in group C (P = 0.012). Accuro Depth was less than Needle Depth [mean difference, 0.85 cm (95% CI−1.10 to − 0.62), SD = 0.62].

Conclusions

Although there was no significant difference in time from Tuohy needle puncture to loss of resistance, Accuro reduced the number of Tuohy needle redirects and accurately indicated the depth to the epidural space. Accuro may be useful for identifying the needle insertion point and estimating depth to the epidural space when residents perform epidural anesthesia.