Thoracic epidural catheters placed by the caudal route in infants: the importance of radiographic confirmation

Background: Cephalad advancement of epidural catheters to the thoracic region via the caudal route has been shown to be feasible in neonates and small infants. This has allowed many young infants to receive thoracic level epidural analgesia with dilute local anaesthetic solutions using the simpler caudal approach. Since radiographic confirmation of the catheter tip is routine at this institution, we wished to determine how often radiographic studies led to adjustment or replacement of the epidural catheter. Methods: After institutional review board approval, we retrospectively reviewed the medical records of neonates and infants less than 6 months of age who had thoracic or lumbar epidural analgesia via the caudal route between August 1995 and January 2000. Demographic data were recorded, including age, weight and type of surgery. The epidural catheter type, tip location by radiograph and any manipulation of the catheter after the radiograph were also noted. Results: During the study period, a total of 115 infants were identified as having received caudal placement of a thoracic catheter. Radiographic studies were available for 86 of these infants. The position of 28 (32%) of the epidural catheters was considered to be inadequate after review of the confirmatory radiograph. Ten of these catheters were determined to be in the high thoracic or cervical region and were pulled back to the desired level. Seventeen of these catheters were coiled in the lumbosacral area and 15 of these were replaced at an adequate level. One catheter was found to be outside the epidural space in the presacral area. No correlation could be found between age, weight, type of catheter or type of surgery and the need for catheter manipulation. Conclusions: Even in young infants, radiographic determination of the catheter tip appears warranted when thoracic catheters are placed via the caudal route.