Venous access ports are medical appliances that can be inserted underneath the skin during a minor surgical procedure. These appliances are used to deliver medicine and other substances directly into a person's circulatory system, especially under circumstances where such treatments are required on a regular basis. After the initial procedure has taken place, it is typically less painful and invasive to insert a needle into a venous access port than directly a vein. This is due to the fact that the ports are located directly underneath the skin. These ports can be connected to major veins such as the jugular, subclavian, and superior vena cava, and can typically withstand several hundred needle punctures before a replacement is needed.
A number of different terms can be used to describe venous access ports. These medical appliances are sometimes called portacaths, which is a result of the words port and catheter being combined. This is due to the fact that each of these appliances is made up of a catheter that connects to a vein, and a silicone port that can be punctured by a needle. The term "totally implanted port" (TIP) is also used to differentiate these appliances from other venous access methods such as peripherally inserted central catheter (PICC) lines.
The two main components of a venous access port are a catheter and a small port that is filled with a self-repairing silicone material. These devices are installed underneath the skin in a surgical procedure, during which the catheter is inserted into an appropriate vein, such as the jugular. The silicone-filled port is then fixed in place under the skin, and the incision is closed. Once a venous access port port has been installed, it is possible to insert a needle through the skin, into the silicone-filled port, and either inject medicine or draw blood. After the needle has been removed, the silicone will tend to naturally close up behind it, though anticoagulants are sometimes injected to prevent clotting.
There are a few different reasons to install a venous access port, all of which are related to ongoing medical treatments. One reason is that some people have issues with their veins, which makes it difficult or impossible to insert a needle each time medicine is needed or blood has to be drawn. Some medical treatments can also damage the veins, in which case a venous access port may be installed ahead of time. These ports are also helpful for patients who require repeated intravenous therapies over the long term, need regular blood transfusions, or are undergoing treatments such as bone marrow transplants.