Notes from the Video

What You're Going to Learn from This Video on Blood Types and Transfusion

What is the ABO blood group system and Rh system? 

What is a type and screen, what is a type and cross?  How do we perform these tests and when should we order them?

These are critical concepts in surgery, concepts you must understand completely.

This is an awesome talk on blood and it covers all of the details you never bothered to learn. Be confident in all of the questions above and rock those questions on your exams.

You are Going to Be Confident Understanding the Following Critical Concepts in Blood Types and Transfusion

1.).The spectrum of acute transfusion reactions

2.) Understand the ABO Blood Group System

3.) Understand the RhD Blood Group System

4.) Understand Type and Screen AND Type and Cross

Two Questions You Need to Be Able to Answer Today!

1.). What type of blood does my patient have?

2.). How do I safely order my patient blood?

Transfusion medicine, typing and crossmatching are difficult topics but once you understand the concept you will crush it, no doubt!

First, what is the ABO Blood Group system?

The ABO blood group system is a classification system for human blood that is based on the presence or absence of certain antigens on the surface of red blood cells.

The system was discovered by Karl Landsteiner in 1900 and is named after the ABO antigens A, B, and O.

There are four main blood types in the ABO system: A, B, AB, and O.

The type of blood a person has is determined by the presence or absence of the A and B antigens on their red blood cells, as well as the presence or absence of the antibodies against these antigens in their plasma.

Blood type A: People with blood type A have the A antigen on their red blood cells and antibodies against the B antigen in their plasma.

Blood type B: People with blood type B have the B antigen on their red blood cells and antibodies against the A antigen in their plasma.

Blood type AB: People with blood type AB have both the A and B antigens on their red blood cells and no antibodies against either antigen in their plasma.

Blood type O: People with blood type O have neither the A nor B antigens on their red blood cells and have antibodies against both the A and B antigens in their plasma.

The ABO blood group system is important in blood transfusions, as transfusing blood of an incompatible type can lead to a potentially life-threatening immune reaction.

For example, a person with blood type A can receive blood from a donor with type A or type O, but not from a donor with type B or type AB. This is because the recipient's immune system will recognize the B antigen on the red blood cells of the type B or AB donor as foreign and mount an immune response.

What is the RhD Blood Group System and Why is it Important?

The RhD blood group system is another important blood group system that is separate from the ABO system.

The RhD system is based on the presence or absence of a specific antigen called the Rh factor on the surface of red blood cells.

People who have the Rh factor are considered Rh positive (Rh+), while those who do not have the Rh factor are Rh negative (Rh-). The Rh factor is named after the rhesus monkey, in which the antigen was first identified.

In general, the RhD system is less complex than the ABO system, as there is only one antigen involved. However, the RhD system is still clinically significant, as transfusing Rh-incompatible blood can also lead to a potentially life-threatening immune reaction.

How about the RhD system in pregnancy?

One of the most important clinical scenarios involving the RhD system is during pregnancy. If a woman who is Rh- becomes pregnant with a fetus who is Rh+, there is a risk of a condition called Rh sensitization.

This can occur if the fetal blood enters the mother's bloodstream, which can happen during pregnancy or delivery.

If the mother's immune system recognizes the Rh antigen as foreign, it may produce antibodies against the Rh factor. These antibodies can then cross the placenta and attack the fetus's red blood cells, potentially causing hemolytic disease of the newborn (HDN) or fetal hydrops.

To prevent Rh sensitization, Rh- women who are pregnant with Rh+ fetuses are often given an injection of a medication called Rh immunoglobulin (RhIg) during pregnancy and again after delivery.

RhIg works by binding to and destroying any fetal Rh+ cells that may have entered the mother's bloodstream, preventing her immune system from recognizing the Rh antigen and producing antibodies.

What is an acute transfusion reaction and what are the major types?

Acute transfusion reactions are adverse reactions that can occur during or shortly after a blood transfusion.

These reactions can range from mild to life-threatening and require immediate recognition and management.

Transfusion reactions can occur, but they are relatively rare. The incidence of transfusion reactions varies depending on the type of reaction and the patient population.

The most common types of transfusion reactions are febrile non-hemolytic reactions, which occur in up to 1% of transfusions, and allergic reactions, which occur in less than 1% of transfusions.

More serious types of transfusion reactions, such as hemolytic reactions and transfusion-related acute lung injury (TRALI), are much less common, occurring in less than 0.1% of transfusions.



There are four main types of acute transfusion reactions:

Hemolytic reactions: These occur when the recipient's immune system attacks and destroys the donor red blood cells. This can happen if the donor blood is not compatible with the recipient's blood type. Symptoms may include fever, chills, chest or back pain, headache, and dark urine.

Allergic reactions: These occur when the recipient's immune system reacts to a protein in the donor blood. Symptoms may include hives, itching, and flushing. Severe allergic reactions, called anaphylaxis, can cause difficulty breathing, low blood pressure, and shock.

Febrile non-hemolytic reactions: These are the most common type of transfusion reaction and occur in up to 1% of transfusions. They are caused by the recipient's immune system reacting to proteins in the donor blood. Symptoms may include fever, chills, and headache.

Transfusion-related acute lung injury (TRALI): This is a rare but serious reaction that can occur when transfused white blood cells attack the recipient's lung tissue, causing fluid buildup and difficulty breathing.

Management of acute transfusion reactions involves stopping the transfusion immediately and providing supportive care, such as oxygen therapy, fluids, and medication to control symptoms. The transfusion reaction should be reported to the blood bank and an investigation should be conducted to determine the cause and prevent future occurrences.

What is the difference between a type and screen and a type and cross?

A type and screen is a blood test that determines the ABO blood type and Rh factor of the recipient's blood and screens for the presence of unexpected antibodies that could cause a transfusion reaction. If unexpected antibodies are found, further testing may be needed to identify the specific antibody and determine compatibility with the donor blood.

A type and cross, on the other hand, is a more thorough test that involves mixing a small amount of the recipient's blood with the donor blood to see if there is any agglutination (clumping) of the red blood cells. If agglutination occurs, it indicates an incompatible match and the transfusion cannot proceed. If no agglutination occurs, the blood is considered cross-matched and compatible for transfusion.

The type and cross is a more specific test than the type and screen, as it takes into account the potential for unexpected antibodies that may not have been detected by the initial screening. It is usually performed when the need for a transfusion is anticipated or if the patient has a history of developing antibodies to red blood cells.

What are the major antibodies identified in a type and screen?

In a type and screen blood test, the major antibodies that are typically identified include:

Anti-A antibodies: These antibodies are produced by individuals with blood type B or O and can cause a transfusion reaction if they come into contact with blood type A.

Anti-B antibodies: These antibodies are produced by individuals with blood type A or O and can cause a transfusion reaction if they come into contact with blood type B.

Anti-D antibodies: These antibodies are produced by individuals who are Rh-negative and can cause a transfusion reaction if they come into contact with Rh-positive blood.

In addition to these major antibodies, a type and screen may also test for other antibodies that can cause transfusion reactions, such as anti-C, anti-E, and anti-K antibodies. The specific antibodies tested for may vary depending on the blood bank's protocols and the recipient's medical history.