Correct location of umbilical arterial and venous catheters on X rays
The umbilical arterial catheter (UAC) should terminate below the L3 vertebra or at the level of the T6 through T9 vertebrae to prevent catheter occlusion of branch vessels arising from the aorta. The umbilical venous catheter (UVC) should terminate at the inferior cavoatrial junction; passage into the right atrium or projection of the catheter over the liver requires repositioning.
The UAC can be identified by its initial inferior extension into the pelvis as it courses from the umbilicus via one of the paired umbilical arteries into an internal iliac artery before it turns to ascend within a common iliac artery and abdominal aorta to the left of the spine. The UVC courses posteriorly from the umbilicus via the umbilical vein through the left portal vein and ductus venosus into the inferior vena cava, where it then ascends to the right of the spine.