The subclavian vein is a vein under the collarbone that brings blood back from the arm. A catheter is a tube system inserted into the body as part of medical treatment. A subclavian catheter may be placed into the subclavian vein if a patient needs medication or nutrition administered intravenously, if a doctor needs to measure the blood pressure inside the vein, or if a patient needs dialysis.
Central venous catheterization is the term for inserting a tube into one of the veins that flow directly to the heart. A subclavian catheter falls into this group because the subclavian vein flows into the jugular vein and then into the heart. A catheter is inserted here instead of in a peripheral vein, such as the back of the hand, in certain cases. These include instances when a patient's peripheral veins cannot handle a catheter and when the drug to be given cannot be administered in a peripheral vein.
The subclavian vein is relatively wide, measuring about 0.4 inch to 0.8 inch (1 cm to 2 cm) in diameter in adults. Medical professionals have a high rate of success in placing catheters in this vein, and an advantage of choosing a subclavian catheter is that the tube is not easily dislodged when a patient moves his head. A disadvantage is that subclavian catheters do carry a higher risk of complications than other central venous catheters.
There are several ways to insert a subclavian catheter. The most commonly used method is to insert a small-diameter needle into the vein and then pass a thin guidewire through the needle. The needle is removed and the doctor uses the guidewire to place the catheter. The doctor also may place a larger-diameter needle into the vein and pass the catheter over this needle into the vein. This method uses a larger needle than the first method, making accidental puncture of an artery more likely.
The last method places into the vein a needle larger in diameter than the catheter. The catheter is then passed through the needle into the vein. This method is only used for certain types of subclavian catheterization, because the hole made by the needle is larger than the catheter, increasing the chance of blood leakage around the hole.
Potential complications of a subclavian catheter include infection, air getting into the vein, broken catheter tips getting into the vein, and a change in heartbeat rhythm. The catheter insertion may also cause a lung to collapse by introducing air around the lung, and the catheter insertion may also damage the chest, causing blood to collect around the lung and prevent it from expanding as normal. These two lung issues are more common with subclavian catheters than with other central venous catheters.