Why do we give a blood transfusion?
to replace or support lost components of the blood.
What are the components of blood?
- erythrocytes or red blood cells (RBCs),
- plasma proteins,
- and clotting factors
Indications for blood transfusions?
anaemia (deficiency or reduction in RBC) or change in RBC quality/haemglobin
haemolysis (haemorrhage) -trauma, surgery
compromised oxygen delivery to tissues -low O2 saturation
What determines a blood type?
- RBC has antigen (a protein) on surface
- antigen elicits response via immune sys
- antigens are individual specific -blood type
Name the dog blood groups
DEA 1-7 +ve and -ve
Name the cat blood types
A, B and AB
Name horse blood types
A, C, D, K, P, Q, U, and T
Describe the characteristics of an ideal blood donor (canine)
- Good size and weight
- Fully immunized
- No parasites
- Not on medications
- Never received a transfusion
- Known blood type that is compatible with recipient
- Good PCV level
Why should an ideal blood donor never have previously recieved a transfusion?
- animals that have received a blood transfusion prior, may have developed antibodies to the antigens on the donors red blood cells,
- without showing a transfusion reaction, this may cause a severe reaction when transfused into a patient.
Describe blood collection method
- ASEPSIS VITAL
- Jugular venepuncture
- Use wide bore IV needle, local anaethesia
- Collection bag containing anticoag, preservative, filters
- gravity fed bag, gently rocked
How many mls of blood can a cat donate?
-sedation usually required
Describe the blood matching process
- 2ml EDTA blood from both animals, labelled
- Centrifuge 1 min at 3000 g.
- Remove plasma to labelled tubes
- Draw up 0.1 ml RBCs, add to 5 ml 0.9% saline, mix.
- Centrifuge this suspension for 1 minute. Discard the supernatant. Add another 5ml saline, mix, centrifuge, discard supernatant, do this washing 3 times.
- In a 3ml test tube put 2 drops of recipient plasma and 2 drops of donor RBC suspension. Mix well, leave at room temp for 30mins.
- In a 3 ml test tube put 2 drops of recipient’s RBCs and 2 drops of donor plasma. Mix well, leave at room temp for 30mins.
- Make controls using donor’s and recipient’s own RBCs and plasma as above.
- Read – check for agglutination and haemolysis; place a drop on a slide and look for agglutination under microscope with 40x magnification. If there is agglutination (clumping) or lysis of the RBC then this indicates the animals are incompatible.
Describe delivery methods for blood transfusion
- largest bore IV catheter
- IV fluid bag set up, 0.9% saline drip
- Blood infusion set (contains in-line filter)
- Specialised infusion pump
- If using frozen products -warm gradually to no more than 37˚C
Describe blood transfusion rates
- INFUSE SLOWLY
- 0.25ml/kg/hr over 30mins
- TPR every 5-10mins for first 1/2 hour
- If no reactions, increase rate to 22ml/kg/24hours
- If blood unused after 4hrs, discard
Signs of transfusion reaction?
- Changes in heart rate and respiratory rate
- Facial swelling
- Tremors, agitation, urination
- Maybe diarrhoea
Signs of blood/fluid volume overload?
- Increased RR
- Nasal discharge
Signs of haemolytic reactions?
- can be acute w/in mins, or delayed up to 21 days
- Muscle tremors
- Renal failure
Signs of non-haemolytic reactions?
(WBC, platelet, plasma protein rxn)
usually transient, non-life threatening