Catheters and catheter supplies can be used for many different reasons: to drain urine from the bladder, drain fluids from abscesses, to administer fluids in the veins (intravenous) – such as medicine or nutrition; to measure blood pressure or intracranial pressure, to administer anesthetic medication into the body, get oxygen into the lungs, or other fluids or organisms into the body such as semen or an embryo.

Catheters were developed centuries ago to drain fluid from the body or to administer medicine. It’s thought that the ancient Syrians created catheters from reeds and that ancient Greeks developed a hollow metal tube to be inserted through the urethra into the bladder. It became known as a “katheter.” It’s also documented that Benjamin Franklin invented a flexible catheter to treat his brother’s bladder stone.

Medical supplies associated with catheters are the tube that is inserted into the body, blood vessel, vein or duct; a flexible, thin tube; or a rigid, larger tube. When catheters are left inside the body permanently or briefly, they are referred to as indwelling catheters. A catheter inserted permanently can be called a permcath. The process of inserting and maintaining the catheter is called catheterization.

When disassembled, most modern catheters have the tube that’s inserted (catheter), a lubricated needle with a luer (a fitting and adapter), a filter, case, and cap. Plastics, silicone and latex are used in constructing modern catheters. Silicone is commonly used because it doesn’t react with fluids in the body or medicines or other fluids. Catheter tips vary in size depending on what size of vessel it is to be inserted, and what fluids or products will be going in and coming out of the catheter.

Many hospitalized patients will encounter some type of catheter to administer medication, to empty the bladder, or to supply nutrition. Often, a central venous catheter will be inserted and kept in place in the arm or chest, or neck, to reach a large vein near the heart. This sounds horribly painful, but the alternative could be numerous intravenous needle sticks. Types of central venous catheters include a tunneled catheter (surgically inserted into a vein and passed under the skin); an implanted port (passed under the skin like a tunneled catheter but the implanted catheter is left entirely under the skin); and the PICC line, (peripherally inserted central catheter that is inserted in the arm). There are advantages to each. Uses vary depending on whether the patient will be mobile, how much daily care is needed, and whether visibility is a factor.