2. Blood Transfusion Flashcards
Why might a Blood Transfusion occur?
- Bleeding (most common)
- Failure of Production
Note - due to Anaemia by any cause
What forms different Blood Groups?
Antigens on the Surface of Red Blood Cells - something which provokes an immune response
What are the 2 categories of Blood Group Systems?
- ABO Blood Types
2. RhD Blood Types
What are the Features of the ABO Blood Type Categories?
- ABO Gene encodes for a Glycosyltransferase
- If someone has Type A Blood, they will have N-Acetyl-Galactosamine on their Red Blood Cells Surface
- If someone has Type B Blood, they will have Galactose on their Red Blood Cells Surface
- If someone has Type AB, they will have Both
- If someone has Type O Blood, they have no Sugars on their Red Blood Cell Surface
What is the Significance of the Sugars on the Surface of the Red Blood Cells?
If you are born with that antigen on the Red Blood Cell Surface (A/B/AB blood type), you will have immune tolerance to it, as the body will identify it as self-attacking
Who can a Patient with:
- Type A Blood, Receive Red Blood Cells from?
- Type B Blood, Receive Red Blood Cells from?
- Type AB Blood, Receive Red Blood Cells from?
- Type O Blood, Receive Red Blood Cells from?
- Type A Patient = Type A / Type O
- Type B Patient = Type B / Type O
- Type AB Patient = Type A / Type B / Type O
- Type O Patient = Type O
Note - Think of the Antigen on the Surface of Each Type, and it being present in this Plasma - If you are Group A you will have Anti-B etc…
Who can a Patient with:
- Type A Blood, Receive Fresh Frozen Plasma from?
- Type B Blood, Receive Fresh Frozen Plasma from?
- Type AB Blood, Receive Fresh Frozen Plasma from?
- Type O Blood, Receive Fresh Frozen Plasma from?
- Type A Patient = Type A / Type AB
- Type B Patient = Type B / Type AB
- Type AB Patient = Type AB
- Type O Patient = Type A / Type B / Type AB / Type O
Note - Think of the Antigen on the Surface of Each Type, and it being present in this Plasma - If you are Group A you will have Anti-B etc…
What is the RhD Blood Group System?
RhD is a Transmembrane Protein which is Immunogenic - You will not make Anti-D unless exposed to it
Note - RhD Negative individuals can make Anti-D if exposed to RhD Positive Cells (Transfusion / Pregnancy)
What can Anti-D cause in pregnancy?
Transfusion Reactions / Haemolytic Disease of the Newborn
What is Screened for in Blood Donors?
- Behavioural Screening - Sex / Age / Location
- ABO / Rh Blood Types
- Infections - Hepatitis B / Hepatitis C / HIV / Syphilis
What are the Different Blood Fractions?
- Red Blood Cells
- Platelets
- Plasma:
- a) Fresh Frozen Plamsa
- b) Cryoprecipitate
- c) Fractionate:
- c) i) Factor Concentrates (e.g. FVIII / FIX)
- c) ii) Immunoglobulin
- c) iii) Albumin
What are the Features of Red Blood Cells from Donors?
- Stored at 4 Degrees
- Shelf-Life of 35 days
- Transfuse over 2-4 Hours
- Indication for use = Anaemia - Surgery / Medical
What are the Features of Platelets from Donors?
- 1 unit of Platelets = 4 pooled / 1 Apheresis Donor
- Stored at 22 Degrees / Shelf Life of 5 days
- Transfuse over 20-60 minutes
- Indications - Massive Haemorrhage / Bone Marrow Failure / Surgery Prophylaxis / Cardiopulmonary Bypass
What are the Features of Fresh Frozen Plasma from Donors?
- 1 unit = 1 unit of Blood
- Stored at Frozen - allow 30 minutes to Thaw
- Indications - Massive Haemorrhage / Disseminated Intravascular Coagulation (DIC) with Bleeding
What Safety Measures are in place for Patient Safety in Blood Transfusions?
- Second Sample - 2 Samples from 2 Different Needles
- Group and Save - ABO and RhD Type (Coomb’s Test)
- Cross Match (Group and Save + Mix of Donor and Sample from Patient to Check for Reaction)
- Samples kept for 7 Days
What Red Blood Cell / Plasma Type would you send for if you only had Minutes?
- O RhD Negative Red Cells
2. AB Plasma
What Red Blood Cell / Plasma Type would you send for if it was an Urgent Situation?
Type Specific (ABO / RhD)
What Red Blood Cell / Plasma Type would you send for if it was a Non-Urgent Situation?
Full Cross Match:
1. Select Correct ABO / RhD Type
2. If Allo-Antibodies choose Antigen Negative Blood
Note - There are many possible Allo-Antibodies in Blood
What are the Key Principles of the Massive Haemorrhage Protocol?
Definitive Management - Rapid Control of Bleeding. Immediate Supply of:
- 6 Units of Red Cells
- 4 Units of Fresh Frozen Plasam
- 1 Unit of Platelets
What are the Risks associated with Transfusions?
- Transfusion of ABO incompatible components
- Transfusion Associated Circulatory Overload (TACO)
- Transfusion Associated Lung Injury (TrALI)
- Acute Haemolytic Transfusion Reaction (AHTR)
When is a Red Blood Cell Transfusion Indicated?
When Haemoglobin falls Below 70
What are the Major Reactions to a Blood Transfusion?
- Fever
- Urticaria
- Respiratory Distress
- Hypotension
- Tachycardia
- Oliguria
- Bleeding
- Collapse
What are the Minor Reactions to a Blood Transfusion?
- Fever < 30 Degrees
- Urticarial Rash
Note - Consider Paracetamol / Antihistamine
Note - These are common
How are Reactions to Blood Transfusions Managed?
- Stop the Transfusion
- Check the Identity against the Component Label
- Consider:
- a) Anaphylaxis
- b) Transfusion Associated Circulatory Overload (TACO)
- c) Acute Haemolytic Transfusion Reaction (AHTR)
- d) Bacterial Infection
- e) Transfusion Associaed Lung Injury (TrALI)
What is the Management of a Transfusion Associated Circulatory Overload (TACO)?
- Slow Rate
- I.V. Diuretic
- Oxygen
What are the Features of Haemolytic Reactions?
- Immediate Complement-Mediated Lysis
2. Shock / High Fever / Renal Failure
What is the Management of Haemolytic Reactions?
- Oxygen
- I.V. Fluids
- Diuretics
- Inotropes
- Dialysis
- Notify the Blood Service to Investigate
What is the Management of Bacterial Infection?
- I.V. Antibiotics
- Oxygen
- I.V. Fluids
- Notify Blood Service
What is the Management of Transfusion Associated Lung Injury (TrALI)?
- Oxygen
- Respiratory Support
- I.V. Fluids
- Notify Blood Service to Investigate / Initiate Recalls
When / How does Haemolytic Disease of the Fetus / Newborn (HDFN) occur?
Development of Maternal Anti-D Antibodies (Sensitisation):
- Mother is Rh Negative Blood Cell Type
- Foetus os RH Positive Blood Cell Type
- RHD + Cells can Cross the Placenta (into the Mother)
- Anti-D can cross into the Foetus
How is Haemolytic Disease of the Newborn:
- Prevented?
- Treated?
- Prophylactic Anti-D - Sensitising Events
- a) Careful Monitoring - Antibody Titres / Doppler Ultrasound / Intrauterine Transfusions
- b) Leucapheresis (Bone Marrow Harvest) / Gene Therapies