Karmakar MK, Li X, Ho AM et al. Br J Anaesth 2009;102:845–54.
This is a relevant and novel piece of work that adds to the knowledge database for performing epidural or combined spinal–epidural anaesthesia using ultrasound guidance. As there are a number of complications associated with locating the epidural space using techniques that rely on anatomical landmarks or loss of resistance, the present authors show that real-time ultrasound guidance is successful in improving epidural access.
In epidural anaesthesia, the current methods of locating the epidural space involve the loss of resistance and the identification of surface anatomical landmarks. However, there are difficulties associated with such techniques, particularly in obese individuals, those with oedema in the back, and those with anatomical abnormalities, which include misidentification of the epidural space leading to multiple needle placement attempts and, thus, discomfort for the patient. In order to overcome such problems, there has been recent interest in the use of ultrasound-guided techniques that enable preview scanning of the anatomy or real-time visualisation during needle insertion. Preview scanning has been reported to improve the success rate of epidural access on the first attempt ; however, no results concerning real-time visualisation have been published. Therefore, the present authors carried out this pilot study to investigate the performance of the real-time ultrasound-guided epidural access technique.