Venous line, central: A catheter (tube) that is passed through a vein to end up in the thoracic (chest) portion of the vena cava (the large vein returning blood to the heart) or in the right atrium of the heart.

Central venous lines have a number of different uses. A central venous line allows concentrated solutions to be infused with less risk of complications. It permits monitoring of special blood pressures including the central venous pressure, the pulmonary artery pressure, and the pulmonary capillary wedge pressures. A central venous line can be used for the estimation of cardiac output and vascular resistance. The near end of the catheter may also be connected to a chamber for injections given over periods of months. A central venous line saves having to have frequent small injections or "drips" placed in the arms. It may also allow a patient to have medicine or fluids at home instead of in the hospital.

The central venous line may be inserted for the short term or long term. There are two types of long term central lines: the cuffed or tunnelled line and the reservoir long line that ends in a rubber bulb or reservoir.

The possible complications of a central venous line include air in the chest (pneumothorax) due to a punctured lung, bleeding in the chest (hemothorax), fluid in the chest (hydrothorax), bleeding into or under the skin (hematoma) and infection. If the line becomes disconnected, air may enter the blood and cause problems with breathing or a stroke.

A central venous line is also called a central venous catheter. Sometimes, the "venous" is omitted and it is called a central line or central catheter.