Katetriin

Katetriin is a flexible tube inserted into the body to drain fluids, deliver substances, or gain access to a hollow organ or vessel. It is used for diagnosis, therapy, and monitoring in many medical settings. Catheters vary by purpose and location and include urinary, vascular, biliary, nephrostomy, and other specialty catheters.

Common categories include urinary catheters (such as indwelling Foley catheters with an inflatable balloon to keep them in place, and intermittent catheters for short-term drainage) and vascular catheters (central venous catheters and peripherally inserted central catheters, or PICC lines) used for medicines, fluids, blood sampling, or monitoring. Other catheters drain bile ducts, remove urine from the kidney, or provide access for imaging and procedures.

Catheters are typically made of latex, silicone, or polyurethane. They vary in size and design, with lumens, side holes, and, in urinary catheters, an inflatable balloon. Many catheters are part of closed systems to reduce infection risk and are designed for single-use or long-term use with appropriate care.

Insertion is performed by trained clinicians under sterile conditions. Some catheters require imaging or ultrasound guidance. Maintenance includes securing the device, keeping the drainage or infusion system closed when possible, cleaning around the insertion site, and removing the catheter as soon as it is no longer needed to minimize complications.

Risks include infection, bleeding, blockage, dislodgement, and tissue injury. Catheter-associated infections are a key concern, mitigated by technique, hygiene, and timely removal.

Historically, catheterization dates to ancient times, with modern indwelling urinary catheters and balloon retention developed in the 20th century; imaging-guided placement and the Seldinger technique followed in mid-century.