👉 Catheterization is a medical procedure that involves inserting a long, flexible tube called a catheter into the body of a patient to deliver medication or fluids. This type of catheter typically consists of an internal diameter of around 20-30 mm and is attached to the patient's body with a silicone or plastic sleeve. The purpose of this insertion is to provide continuous access to the bloodstream for various medical treatments, such as blood tests, medications, or fluids.