A tunneled catheter is a medical device used to access the bloodstream for long-term treatments, such as chemotherapy or dialysis. It is inserted under the skin and runs through a tunnel to a large vein, allowing for easy access without repeated needle sticks. This type of catheter is designed to remain in place for weeks or months. Tunneled catheters are typically made of flexible materials and come in various sizes. They are often used in patients who require frequent blood draws or medication administration. Proper care and maintenance are essential to prevent infections and ensure the catheter functions effectively.