A chemotherapy pump, also called a chemo pump or an infusion pump, is a medical device that intravenously injects chemotherapy drugs into the patient's bloodstream at a set rate. These pumps are commonly used in the treatment of cancer, either by themselves or in combination with other cancer treatments such as radiotherapy or surgery. They are useful for treatments that require a steady flow of individually small doses of a drug, because they can do this automatically and precisely in a way that would be impractical if a doctor or nurse had to manually administer every individual dose. Some chemotherapy pumps are portable, either worn by the patient or implanted in his or her body, and so allow chemotherapy to be administered with less disruption of the patient's daily life.
An external chemotherapy pump administers chemotherapy drugs to the patient through a flexible tube. This can be done through either a tube called a cannula that goes into a blood vessel in the patient's hand or arm or via a catheter inserted into a blood vessel in the chest, called a central line. The pump can be a device in a hospital, in which case the patient will need to visit the hospital for each treatment or remain there for an extended period of time, or a device that the patient can take home. Some modern chemotherapy pumps are small enough that they can be carried on the patient's person in a pouch or holster, allowing him or her to receive treatment from the chemotherapy pump while going about his or her normal activities.
An internal chemotherapy pump is a surgically implanted device that is placed inside the body, usually just under the skin of the chest. The pump contains a reservoir of the patient's chemotherapy drugs, which it pumps through the central line catheter at appropriate times. Some internal chemotherapy pumps, used to treat cancer of the liver, are instead implanted under the skin in the abdomen and pump chemotherapy drugs directly into the hepatic artery that goes to the liver, concentrating treatment on the affected area and so allowing treatment to be done with lower levels of the drugs and fewer side effects. The surgery to implant this type of device, called a hepatic artery infusion pump, is somewhat more involved and usually includes surgically removing the patient's gallbladder. Both types of pump contain an internal reservoir that stores the drug, which must be periodically replenished.