A tunnelled central venous catheter (also called external catheter or central line) is a long, flexible tube. One end of the catheter is placed in or near the right atrium of the heart and the other end is outside the skin of the chest. The tube tunnels under the skin of the chest, enters a large vein near the collarbone and threads inside the vein into or near the right atrium of the heart.
There are many benefits to having a tunnelled central venous catheter rather than a regular IV. The most important benefit is that it reduces the number of needle sticks. However, it is important not to tell children that having a tunnelled central venous catheter means they will never have to be “poked” again, since they may still need needle sticks for some blood tests.
When the person needs IV therapy, the IV tubing is connected to the end of the catheter outside the body. The fluid or medicine flows through the IV tubing into the catheter, then into the bloodstream. After treatment is over, the IV tubing is removed and a new cap is placed on the end of the catheter.