Catheter

Catheter

In medicine, a catheter is any hollow thin flexible tube designed to be inserted into the body. The process of inserting a catheter is called catheterization.

Catheters are used for:

draining urine from the bladder, see urinary catheterization
administering fluids, intravenous medication or parenteral nutrition into a vein
injecting dye into blood vessels or other structures to visualize abnormalities, as in cardiac catheterization, also known as coronary angiography
measuring blood pressure directly in a blood vessel

A central line is a conduit for giving drugs or fluids into a large-bore catheter positioned either in a vein near the heart or just inside the upper chamber of the heart itself (in the atrium).