What is a central line?

A central venous catheter, or a central line, is a thin and flexible tube that is inserted into a patient's arm or chest, according to WebMD. The tube then delivers medicine, fluids, blood products or nutrients to a patient for an extended period of time.

A health care worker inserts a central line into a patient's arm or chest through the skin into one of the larger veins, states WebMD. The long, thin tube is then threaded through the patient's vein until it reaches a large vein near the patient's heart. This allows doctors and nurses to deliver medications to the patient's bloodstream quickly and efficiently.