An infusion port is a medical device that is surgically implanted under the skin for long-term use. It has a catheter and a port, which draws blood out of a vein, through the port into the catheter, and then infuses it back into the vein. This device avoids the pain of repeated puncture of the vein and reduces the risk of infection. It is often used for patients who need long-term infusions, such as cancer patients or those who need to undergo long-term treatment.