Interpreting the results of pediatric central venous catheter studies.

Radiographic evaluation of central venous catheters (CVCs) with contrast material is a commonly performed procedure in pediatric radiology, but the criteria for interpreting the results of such studies are not well described in the literature. Careful evaluation of the images from a contrast material-enhanced CVC study frequently demonstrates a cause of CVC malfunction. In a series of 166 contrast-enhanced CVC studies performed in children, 112 studies (67%) demonstrated abnormal results. The most common abnormalities were mural thrombus, catheter tip thrombus, catheter tip against the vessel wall, and sleeve thrombus. Other causes of catheter malfunction include reservoir thrombus, catheter break, and catheter malposition. When catheter malfunction is due to catheter thrombus formation, the patient is usually treated with urokinase (bolus injection or infusion). Short catheters that ended in the innominate or subclavian vein had a much higher frequency of abnormalities than longer catheters that ended in the superior vena cava or right atrium.