A Service Evaluation of Ultrasound Assessment of the Epidural Space: A Retrospective Audit

Abstract

Interest in the ultrasound assessment of the epidural space prior to regional anaesthesia is becoming extremely popular. The published data to date comes mainly from single operators performing scans in clinical trial settings. The clinical data from a busy teaching unit has been examined to see how it compares with standards in the published literature. 114 scans were performed by a total of 6 consultant anaesthetists as part of their normal clinical work. The majority of scans were performed for either maternal obesity (72%) or training (18%). The difference between the ultrasound assessed depth and needle depth was 0.25 +/– 0.7 (mean +/– sd) cm. The correlation coefficient (r) for these two variables was 0.86. This data suggests that the ultrasound reliably measure depth of epidural space in a routine clinical setting.