Detection of epidural catheters with ultrasound in children

Summary Background: The aim of this study was to assess whether a noninvasive imaging technique such as ultrasound could visualize an epidural catheter in the epidural space in children. Methods: Following local ethics committee approval and informed parental consent a pilot study of 12 cases was performed. Children undergoing major surgery requiring epidural analgesia were recruited. All catheters were introduced via the lumbar region. All children were scanned within 24 h of epidural insertion by consultant paediatric radiologists. If the catheter was identified in the epidural space then an attempt was made to visualize the entire length of the catheter. Results: The epidural catheter was detected in nine of 12 patients. All of these were less than 6 months old. The entire length of the catheter was visualized in five of the nine patients. It was possible to estimate the most cephalad level of the catheter in seven of the nine patients. This was in the thoracic region in all cases and an appropriate level for the intended surgical procedure. It was not possible to precisely identify the tip of the catheter as a distinct entity using ultrasound. Conclusion: This study shows that it is possible to visualize an epidural catheter in the epidural space in children under 6 months of age using ultrasound.