Blood transfusion Flashcards
What A and B plasma antibodies will blood-antigen groups A,B,AB and O have?
antigen A = anti-B
antigen B = anti-A
antigen AB = none
antigen O = anti-A and anti-B
What kind of immunoglobulin are anti-A and anti-B antibodies?
IgM (no placenta crossing)
What do anti-A and anti-B antibodies cause in the blood?
Agglutination RBCs
What are red cell antigen alloantibodies?
an IgG antibody against red cell antigens. These can develop when people recieve blood transfusions
Issues formed when patients are transfused?
Pt cannot be a blood donor in the future
When should a patient be transfused?
When other alternative treatments are not sufficient (treat underlying cause with anaemia/platelets for thrombocytopenia/use manufactured products for plasma)
How many blood samples are needed to confirm a the correct blood group?
two
What are possible complications of blood transfusions?
Haemolytic reactions
Allergic reactions
Anaphylaxis
Infection
Immune sensitization
Type of hypersensitivity reaction when wrong ABO blood is given to a pt?
Type II hypersensitivity
When do antibodies to RhD develop?
After someone has been exposed RhD antigens via transfusion, pregnancy, transplant
Potential issues with RhD antibodies developing and pregnancy?
If mother is RhD neg and baby RhD pos, if mother exposed then she’ll develop anti-RhD antibodies
Big issue for second pregnancy as anti-RhD antibodies can cross placenta causing haemolytic disease of newborn
What type of Ig is anti-RhD antibodies?
IgG
What is ‘group and screen’?
technique to confirm blood donor / receiver compatibility
confirm ABO and Rh groups
screen serum for important antibodies in direct antiglobulin test
What is crossmatching?
- Another form of patient / donor compatibility screening
- Donor cells are tested against the patient’s serum, mixed + incubated and any agglutination is detected visually or microscopically
- If agglutination is noted it means the donor + patient are not compatible
What is electronic issue?
- If 2 separate group + screen tests have been carried out, with negative antibody screens, then ABO and Rh compatible blood can be given to the patient without further compatibility testing
- NB: not valid if any blood has been transfused between the 2 separate group + save screening tests
What is fresh frozen plasma and when is is used?
Plasma stored frozen
- Replacement of coagulation factors when specific concentrates are unavailable
- Massive transfusions
- Liver disease
- Disseminated intravascular coagulation (DIC)
- Cardiopulmonary bypass surgery
- Reversal of warfarin effects
- Thrombotic thrombocytopenic purpura
What is cyroprecipitate?
Cryoprecipitate is a blood product that is obtained by thawing fresh frozen plasma (FFP) and then collecting the precipitate that forms.
Contains concentrated factor VIII and fibrinogen.
When is cyroprecipitate used?
- Fibrinogen deficiency Replacement
- Massive Transfusion
- Use after 4-10 for rbcs units
- Hepatic Failure
What is prothrombin complex concentrate and when is it used?
Blood product - contains clotting factors II, VII, IX, X and protein C and S
- Reversal of anticoagulation with vitamin K antagonists (e.g., warfarin)
- Urgent reversal of life-threatening bleeding associated with vitamin K antagonists
Describe transfusion-associated circulatory overload (TACO)?
Too much fluid being transfused too quickly
Pulmonary oedema and acute respiratory failure
How to prevent TACO?
risk assessment pre transfusion
prescribe by volume
use diuretics
slow transfusion
Investigation and Management of TACO?
Bloods – leukopenia, eosinophilia
- IV furosemide – diuretic
- High flow oxygen
what is Transfusion Related Acute Lung Injury?
Donor plasma contains antibodies against patient’s leukocytes
Acute respiratory distress
Presentation of Transfusion Related Acute Lung Injury?
Within 6 hours:
- Non-productive cough
- Dyspnoea
- Hypoxia
- Frothy sputum
- Fever
- Rigours
Investigation and management of Transfusion Related Acute Lung Injury?
CXR: multiple perihilar nodules, infiltration in lower lung
- High flow oxygen
- IV fluids
- Inotropes
- ABGs
- Chest x-rays
- Consider ventilation and ICU
What is acute (IgM) haemolytic reaction?
Incompatible red blood cells react with patient’s antibodies
activates pts complement system
acute reaction
Diagnosis and management of an acute haemolytic reaction?
Presents with changes associated with haemolytic anaemia
Oxygen
- Fluids
- Diuretics
- Inotropes – increases vasoconstriction
- FFP (fresh frozen plasma)/platelet transfusion
What is delayed (IgG) haemolytic reaction?
5-10 days post transfusion
Patient had previously had an immune response to a red blood cell antigen either from pregnancy or transfusion. After a second transfusion that contains that antigen, a secondary immune response occurs.
Management of delayed (IgG) haemolytic reaction?
- IV immunoglobulin
- Erythropoietin
What increases the risk of delayed (IgG) haemolytic reaction?
developing antibodies against non-AB and non-Rh D antigens from previous transfusions/ pregnancy
