BLOOD TRANSFUSIONS Matching and Transfusing

ABO Karl Landsteiner identified the O, A, and B

blood types in 1900.

Alfred von Decastello and Adriano Sturli discovered the fourth type, AB, in 1902.

Antigen – marker expressed on the call wall

Antibodies – used by the immune system to neutralize pathogens

ABO Type A blood has type A antigen expressed on its

surface.

Type B has type B antigen expressed on its surface.

Type AB has type A & B antigen expressed on its surface.

Type O (sometimes referred to as type zero outside North America) has no antigen expressed on its surface.

Depending on the blood type different antibodies (anti-A, anti-B, or anti-A & anti b) will be present in the blood.– Type A: anti-B antibodies– Type B: anti-A antibodies– Type AB: no antibodies– Type O: anti A & anti B antibodies

RHESE FACTOR Discovered in 1937 by Karl Landsteiner and

Alexander S. Wiener.

Rh positive indicates that the type D antigen is expressed.

Rh negative indicates that the type D antigen is not expressed.

You need to be exposed to antigen D (Rh +) to develop antibodies (i.e. mother-fetus)

Furthermore, many other antibodies exists and many be tested for in unique clinical situations.

ABO +/-TYPE ANTIGEN ANTIBODIESA + A & D Anti-B antibodies

A - A Anti-B antibodies

B + B & D Anti-A antibodies

B - B Anti-A antibodies

AB + A, B & D No antibodies

AB - A & B No antibodies

O + Zero Anti-A and Anti B antibodies

O - Zero Anti-A and Anti B antibodies

Therefore, PRBC must be matched to prevent a hemolytic reaction.

ABO +/- Blood Transfusions:

• AB+ is the universal recipient because the RBC expresses the A, B and D antigen. Therefore, any type of blood can be transfer without an antibody reaction.

• O- is the universal donor. Type O or type ‘zero’ has no A, B or D antigens expressed on its surface. Therefore, when transfused it won’t create an antibody reaction.

• Rh (+) recipients may receive a type specific Rh (-) transfusion (A+ received A-).

• However, Rh (-) recipients may not receive a Rh (+) transfusion. D antibodies will develop causing a transfusion reaction.

BLOOD TRANSFUSIONS Initially, whole blood was transfused.

Modern transfusion medicine developed component therapy.

Whole blood is broken down into different products (PRBC / FFP / PLT / CRYO / ALB / ect).

Whole blood used in military trauma centers.

Massive Transfusion Protocol attempts to mimic whole blood (ratio of PRBC:FFP:PLT)

PRBC ABO Rh specific Improve oxygen delivery (VO2) Replace lost volume (↑ Hgb & HCT) Cold (4C) Leukocyte reduced (reduces transfusion

reactions) Contains citrate Storage: 35 days K+↑ and 2,3 DGP ↓ with age Limited ATP stores Shape changes during storage (oval shaped)

TRANSUSION REACTIONS Acute Hemolytic Transfusion Reaction (AHTR) Delayed Hemolytic Transfusion Reaction (DHTR) Febrile Non-hemolytic Reaction Allergic Reaction Anaphylaxis Transfusion Related Acute Lung Injury Acute Non Hemolytic Reaction

!! DANGER !!

TRANSUSION REACTIONSAcute Hemolytic Transfusion

Reaction:

• ABO incompatibility (40% lab error / 60% bedside error)

• Fever, chills, chest pain, shock, bleeding, death

• Rapid onset (antibody mediated)

TRANSFUSION REACTIONS

Delayed Hemolytic Transfusion Reaction:

• Seen in patients with multiple previous transfusion or pregnancy.

• Antibodies develop to other antigens (not A, B or O).

• Develops days to weeks after the transfusion.

TRANSFUSION REACTIONS

Allergic Reaction Anaphylaxis:

• Allergic reactions are common in transfusion recipients (1-3%).

• Reaction to the donor proteins, leukocytes and antigens.

• Anaphylaxis (rare): severe life threating allergic reaction.

TRANSFUSION REACTIONSTransfusion Related Acute Lung Injury:

• Transfusion of inflammatory cytokines, active lipids, and/or antibodies.

• Immune and inflammatory response in the patient’s lungs (diffusing problems).

• Respiratory distress (secondary ARDS)

• Sick patient + transfusion = TRALI

TRANSFUSION REACTIONS

Acute Non-Hemolytic Reaction:

Delayed onset (<1 hour)

Leukocyte mediated

Cooled donor leukocytes less active.

Leukocytes become more active as they warm up.

TRANSFUSION COMPLICATIONS Transfusion associated sepsis

Fluid Overload

Metabolic Effects:• Hyperkalemia (especially in patient with acidosis and renal failure)• Citrate Toxicity: ↓Ca+ and metabolic alkalosis

Hypothermia • Associated with poor outcomes• Warm blood when possible

Thank You!