What precautions are taken during blood transfusion?

Blood transfusions are an important part of emergency medical services and operative procedures, but it's not as simple as taking blood from one person and putting it into another. There are several different types of blood with certain antibodies which aren't always compatible with one another. What's more, many illnesses may be passed on through blood. To make sure that someone receiving a blood transfusion doesn't become sick from or have an allergic reaction to the blood, several things happen prior to the actual transfusion.

First, when a person donates blood, he or she must be clear of any blood-borne illnesses like Human Immunodeficiency Virus or Hepatitis. It's also helpful if someone can state their blood type when making a donation, although blood can be tested afterwards. Blood is packaged in sterile plastic bags and then clearly labeled. There are eight different types of blood based on antibody compositions — A, B, AB, and O, each of which may be either RhD positive or negative. Blood may go through additional screening for potential illness-causing agents or be separated for special-purpose transfusions of white or red blood cells, platelets, or plasma.

After any additional screening or separation, blood is sent to a hospital or doctor's office, where it remains in a refrigerated storage space to prevent cell degradation. When a patient needs a transfusion, medical staff always double check a person's blood type before administering an intravenous transfusion. Giving a patient the wrong type of blood can make them break out in a serious reaction as their body's immune system tries to fight off foreign antibodies. Some people can receive or donate any type of blood regardless of antibody composition. Type O+ blood is considered the "universal recipient" of blood products, while type O- is the "universal donor."

When it's time to give the transfusion, an intravenous catheter is inserted. The area is cleaned with an alcohol swab and a fresh, sterile needle is used to create the puncture. The catheter is then flushed with saline solution to make sure there is no tissue or blood cells blocking the portion inside of the patient's vein. Blood transfusions are typically co-administered with saline solution in a slow fashion to prevent any shock to the body. In emergency situations where someone has lost quite a lot of blood or has inadequate platelets, a transfusion might be done more quickly.

Perhaps the most important part of precautions for blood transfusions is the routine testing of blood for pathogens. This screening, performed by organizations like the Center for Disease Control, ensures a healthy and safe supply of blood is available for people who need it.