Umbilical venous catheter position: evaluation by ultrasound

Umbilical venous catheter (UVC) insertion is frequently performed in critically ill neonates, with catheter position evaluated by an abdominal radiograph. The position of the catheter can be difficult to assess based on supine film alone. We aimed to determine whether ultrasound enables precise evaluation of the catheter tip position. We prospectively evaluated UVC position in 75 neonates by ultrasound and supine abdominal radiograph. Distance from the catheter tip to the diaphragm was measured for both modalities. Anatomical location of the catheter was recorded for both studies. The Student's t-test was used to compare the means of the differences in catheter position on radiograph and ultrasound. In 46 patients there was no difference in the distance between the catheter tip and the diaphragm on ultrasound and radiograph. In 29 babies there was a difference of 1-to-7 mm. Ultrasound identified malposition of the catheter in three cases in which the position of the catheter on the plain film was deemed acceptable. Our study suggests that ultrasound is reliable and may replace plain radiograph for the identification of the UVC position, preventing complications from malposition, and reducing exposure to ionizing radiation.