Blood Transfusion Flashcards
What indications are there for blood transfusion?
Hypovolaemic anaemia (e.g. blood loss).
Euvolaemic anaemia (e.g. IMHA).
Coagulopathies e.g. rodenticide toxicity.
Thrombocytopenia and thrombopathia?
Hypoalbuminaemia?
? – In practice, platelets may not survive the process.
- When are blood products indicated for anaemic patients?
- What other measurements could be an indicator but not a solo indicator?
- When there are clinical signs of anaemia.
– Weakness.
– Tachycardia.
– Tachypnoea.
– Indirect measures of poor oxygen delivery e.g. high blood lactate. - PCV value.
Blood products available in the UK for dogs.
Whole blood.
Packed red blood cells (PRBCs).
Fresh frozen plasma and frozen plasma.
Cryoprecipitate and cryoprecipitate poor plasma.
Blood products available for cats in the UK.
Whole blood (more so locally).
– Feline blood banks currently in their infancy.
– Whole blood obtained from consenting clients, friends, family, colleagues.
– Obtained from local donor colonies.
– Obtained from donors from the animal blood register.
Processing of blood to make blood products.
Collect whole blood.
– Hard spin this blood to get packed red blood cells (PRBCs) and fresh frozen plasma.
–> Fresh frozen plasma either slowly and partially thawed and centrifuged to get cryoprecipitate and cryoprecipitate poor plasma.
–> or 1 year old fresh frozen plasma or fresh frozen plasma that is thawed and then re-frozen is called frozen plasma.
– Light spin this blood to get packed red blood cells (PRBCs) and platelet rich plasma.
–> Platelet rich plasma further processed to produce fresh frozen plasma and platelet concentrate.
Fresh whole blood.
Used soon after collection (<6 hours).
Contains physiological concentrations of red blood cell, SOME functional platelets, proteins and coagulation factors.
Stored whole blood.
Used >8 hours after collection.
No functional platelets, loss of labile clotting factors (V, VIII, vWF)
Packed Red Blood Cells (PRBCs).
Separated from plasma by centrifugation (hard spin).
PCV higher than of whole blood – usually 70-80%.
Fresh Frozen Plasma (FFP).
Stored at -20 to -40 degrees C, <1 year.
Contains ALL coagulation factors.
Contains physiological levels of albumin and other plasma proteins.
No RBCs.
Frozen plasma (FP).
FFP that is >1 year older OR that has thawed and been re-frozen.
Stable coagulation factors will remain.
Labile factors will be lost (e.g. V, VIII, vWF).
Stored at <-18 degrees C for up to 5 years.
Still contains physiological levels of albumin.
Cryoprecipitate (cryo).
Made by slowly and partially thawing fresh frozen plasma which is then centrifuged again.
Cryoprecipitate is the precipitate collected from this second centrifugation.
Rich in fibrinogen, VIII, vWf.
Principle of deciding what your specific patient needs.
Replacing like with like. Use the product that most closely replaces what is missing.
Why do we use specific products for specific patients?
To use blood products efficiently.
To save more lives with a single unit of blood.
To reduce the risk of the patient developing transfusion reactions and complications.
- What is the ideal product for blood loss anaemia? – what other products could be appropriate?
- What product can be used for thrombocytopenia/pathia?
- What is the ideal product for unknown coagulopathy? – what may also be appropriate to use?
- What is the ideal product for rodenticide toxicity? – what may also be used?
- What is the ideal product for von Willerbrand Disease / haemophilia A. – What else may be used?
- What would be the ideal blood product for IMHA?
- Fresh whole blood. – Stored whole blood, packed red blood cells.
- Fresh whole blood.
- Fresh frozen plasma – Fresh whole blood.
- Frozen plasma. – Fresh frozen plasma.
- Cryoprecipitate – FFP, FWB.
- PRBCs.
What other consideration must be made when selecting a blood product?
– why?
Blood type. – RBCs possess antigens on their surface and the plasma may contain antibodies.
If given a transfusion with the wrong blood type, antibodies may react with the antigens in the donated blood = transfusion reaction.
Transfusion reaction symptoms.
Fever
Tachycardia
Dyspnoea
Muscle tremors
Vomiting
Weakness
Collapse
Haemoglobinemia
Haemoglobinuria