Main Page | See live article | Alphabetical index 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). See also: cannula This article is from Wikipedia. All text is available under the terms of the GNU Free Documentation License.