What happens if different blood types are mixed

However, you can only donate blood to other people who have type AB blood. You can give your blood to anyone without triggering their immune system, but you can only receive type O blood.

Before a blood transfusion, your doctor will test your blood to determine your blood type. A small sample will be crossmatched with some of your donated blood. The two samples of blood are then mixed and watched for a reaction.

Human error is the most likely cause of an ABO incompatibility reaction. If your transfusion uses the wrong blood type, it could be the result of mislabeled blood, incorrectly completed forms, or a failure to check donated blood before the transfusion.

These may include:. Medical staff will stop the blood transfusion if they suspect you might be having an incompatibility reaction. Learn more: Transfusion reactions ».

Your doctor will test samples of your blood for evidence of destruction of your red blood cells. While these procedures are performed, your doctor or nurse will monitor your vital signs, including your:. You may need to enter the intensive care unit.

After stopping your blood transfusion, the medical staff will attach a saline drip to the line to keep it open. You may receive oxygen and intravenous fluids. You may also receive a drug to increase your urine output. However, most hospitals and blood banks have systems in place to reduce the chance that such a reaction will occur. Before you get a blood transfusion, your blood is tested to find out your blood type.

And the blood you will get in the transfusion is tested to make sure it matches your blood. You may have a mild allergic reaction even if you get the correct blood type. Signs of a reaction include:. A mild reaction can be scary, but it rarely is dangerous if it's treated quickly. The most important blood type classification systems are the ABO system and the Rh system.

Each type of blood in the ABO system also has a positive or negative Rh factor. If you get blood in a transfusion that isn't the right type, you may have a transfusion reaction. A mild transfusion reaction rarely is dangerous, but you must get treatment quickly. A severe transfusion reaction can be deadly. Blood banks collect blood from volunteer donors. Before they donate, volunteers must answer questions about their current health, health history, and any diseases they may have been exposed to through travel to foreign countries, sexual behaviour, drug use, or needle sticks such as from tattoos.

Only people who pass this survey are allowed to donate blood. Donated blood is then carefully tested for certain diseases and to find out the blood type. If there is any chance that the blood may not be safe to use, it is thrown away. Most blood that passes the tests is then split into its components and sent out for use. Blood and its components can be stored or used for only a short time before they must be thrown away.

This is why blood banks are always looking for donors. Transfusions are used to treat blood loss or to supply blood components that your body cannot make for itself. Blood loss may result from injury, major surgery, or diseases that destroy red blood cells or platelets , two important blood components.

If too much blood is lost low blood volume , your body cannot maintain a proper blood pressure, which results in shock. Blood loss can also reduce the number of oxygen-carrying red blood cells in the blood, which may prevent enough oxygen from reaching the rest of the body.

Whole blood is rarely given to treat blood loss. Instead, you are given the blood component you most need. If you have lost too many red blood cells or are not making enough of them, you are given packed red blood cells. If you have lost a great deal of blood, or if your clotting factors or platelets are low or abnormal, you may also need a transfusion of either of these to help control bleeding.

Sometimes you may need replacements of some blood substances if your body does not make enough of them. For example, you may be given substances to help your blood clot clotting factors if you do not have enough of them naturally. Blood lost during surgery sometimes can be recovered, cleaned, and returned to you as a transfusion. This greatly reduces the amount of blood you might otherwise need to receive.

Receiving your own blood back is safer, because there is no chance of a reaction. One blood component that affects the blood's ability to clot is platelets. A reduced number of platelets thrombocytopenia or the failure of platelets to function properly increases the time it takes for bleeding to stop increased bleeding time. Transfusion with platelets improves the clotting time, which reduces the risk of uncontrolled bleeding.

This treatment does not cure the cause of platelet loss. Anemia is a decrease in the number of oxygen-carrying red blood cells or a decrease in the amount of hemoglobin , the oxygen-carrying substance in the red blood cells.

There are several types of anemia, each with a different cause, and each is treated differently. Severe anemia may be treated with a transfusion of packed red blood cells. This temporarily increases the number of oxygen-carrying red blood cells in circulation and may improve symptoms, but it does not treat the cause of the anemia.

Almost all of the blood used for blood transfusions is donated by volunteers. For details on the donation process, see Donating Blood. The TPD enforces five layers of overlapping safeguards to protect the blood supply against disease. These safeguards are implemented by Canadian Blood Services, the national organization that collects and distributes blood and blood products in all provinces and territories except Quebec.

Your blood is typed, or classified, according to the presence or absence of certain markers antigens found on red blood cells and in the plasma that allow your body to recognize blood as its own. If another blood type is introduced, your immune system recognizes it as foreign and attacks it, resulting in a transfusion reaction.

People with type A have antibodies in the blood against type B. People with type B have antibodies in the blood against type A. People with AB have no anti-A or anti-B antibodies.

People with type O have both anti-A and anti-B antibodies. People with type AB blood are called universal recipients, because they can receive any of the ABO types.

People with type O blood are called universal donors, because their blood can be given to people with any of the ABO types. Mismatches with the ABO and Rh blood types are responsible for the most serious, sometimes life-threatening, transfusion reactions. But these types of reactions are rare.

The Rh system classifies blood as Rh-positive or Rh-negative, based on the presence or absence of Rh antibodies in the blood. People with Rh-positive blood can receive Rh-negative blood, but people with Rh-negative blood will have a transfusion reaction if they receive Rh-positive blood. Transfusion reactions caused by mismatched Rh blood types can be serious. There are over other blood subtypes.

Most have little or no effect on blood transfusions, but a few of them may be the main causes of mild transfusion reactions.

Mild transfusion reactions are frightening, but they are rarely life-threatening when treated quickly. The risks of blood transfusions include transfusion reactions immune-related reactions , non-immune reactions, and infections.

Immune-related reactions occur when your immune system attacks components of the blood being transfused or when the blood causes an allergic reaction. This is called a transfusion reaction. Even receiving the correct blood type sometimes results in a transfusion reaction. These reactions may be mild or severe. Most mild reactions are not life-threatening when treated quickly. Even mild reactions, though, can be frightening. Mild allergic reactions may involve itching, hives, wheezing, and fever.

Severe reactions may cause anaphylactic shock. Doctors will stop a blood transfusion if they think you are having a reaction. An antigen is any kind of molecule, such as a protein or a carbohydrate, that can be recognised by the immune system—the antibodies target whichever antigens it identifies as being foreign invaders.

It is important though for the antibodies to not identify antigens that do belong. For example:. The immune system will go into attack mode and antibodies will be produced to help fight off the unfamiliar visitors. Antibodies attack by binding to the foreign antigens on the surface of red blood cells.

This ultimately causes those red blood cells to rupture, destroying them entirely. In small amounts, rejected blood can be filtered out by the kidneys, but larger transfusion amounts could cause kidney failure and, potentially, death.