Chemotherapy is a common treatment for patients with cancer. It is designed to selectively destroy cells that are very rapidly dividing. Because cancer cells divide more quickly than normal cells, they will be more affected by the chemotherapy.
Most chemotherapeutic agents cannot be taken orally because they are either poorly absorbed by the digestive tract, or because the body inactivates them after they are ingested. As a result, many types of chemotherapy drugs are given intravenously. The most effective way of administering these drugs is by injecting them in the superior vena cava vein directly above the heart so the drug is pumped throughout the body quickly and efficiently. Because chemotherapy often is given multiple times per week and it can be difficult to inject these medications into large veins, a port may be installed to make the injections easier.
In general, the installation of a port for chemo is considered to be a fairly minor surgical procedure and can be done as an outpatient procedure with local anesthesia and "conscious" sedation (i.e. the patient is never rendered unconscious). The procedure begins with disinfection and numbing of the area where the port will be placed (typically the upper chest). Then a large needle is inserted into the chest. This needle is then used as a conduit to allow a catheter (which is a small tube) to be threaded into the superior vena cava. This catheter is attached to the port, which will then remain outside of the body. The needle is then removed and the port is in place.
One risk that a port for chemo presents is that it can allow bacteria access to the body, where it can cause a severe infection. Though the risk of this is relatively low, patients receiving chemotherapy are already weakened by the cancer and the treatment, and these infections can be life threatening. The port can also cause the blood around it to clot, which can not only cause blood clots but can also block off the port. This is why every time the port is used it needs to be washed out with saline solution as well as heparin, which is a blood thinning medication. During insertion of the port, there is also a risk of damaging the vein or puncturing the lungs, so the patient needs to be monitored after the procedure.