Blood transfusions

Question 1

what blood products are available for dogs?

Answer 1

• whole blood
• packed red blood cells
• frozen plasma
• cryoprecipitate and cryoprecipitate poor plasma

Question 2

what blood products are available for cats?

Answer 2

• no pet blood banks for cats
• whole blood obtained locally:
  
  • cats of consenting clients, friends, family, colleagues
  • local donor colonies
  • donors from animal blood register

Question 3

process of centrifuging whole blood into other products

Answer 3

whole blood + hard spin-> packed RBC +fresh frozen plasma

fresh frozen plasma + centrifuge-> cryoprecipitate + frozen plasma

Question 4

fresh whole blood (FWB)

Answer 4

• used soon after collection <6hrs
• contains physiological concentrations of RBCs, some functional platelets, proteins and coagulation factors

Question 5

stored whole blood (SWB)

Answer 5

• stored >8hrs
• no functional platelets, loss of labile clotting factors
• PCV= 45%

Question 6

conditions of storing whole blood

Answer 6

• 2-6 degrees
• max 21 days

Question 7

fresh frozen plasma (FFP)

Answer 7

• contains all coagulation factors
• physiological concentrations of albumin and other proteins
  storage= -18 degrees for less than 1 year

Question 8

frozen plasma (FP)

Answer 8

• FFP that is >1yr or thawed and refrozen
• stable coagulation factors
• no labile factors
  storage= -18 degrees for up to 5 years

Question 9

cryoprecipitate (cryo)

Answer 9

• precipitate collected from second centrifugation
• rich in fibrinogen, VIII, vWf (laible clotting factors)

Question 10

common diseases that may benefit from blood transfusion

Answer 10

• those that result in deficiency of blood constituent (hypovolaemic anaemia, euvolaemic anaemia, coagulopathies)

Question 11

when is blood transfusion indicated for anaemic patients?

Answer 11

• not based purely on PCV value
• if clinical signs (weakness, tachycardia, tachypnoea, measures of poor O2 delivery (high blood lactate))

Question 12

transfusion reaction symptoms

Answer 12

• fever
• tachycardia, dyspnoea
• muscle tremors
• weakness, collapse
• haemoglobinemia, haemoglobinuria

Question 13

blood types in dogs

Answer 13

• dog erythrocyte antigen (DEA)
• DEA1 (most antigenic, causes transfusion reaction)
• dogs don’t possess any naturally occurring antibodies against DEA1 (first transfusion can be given untyped)
• DEA1 negative patients need the same
• DEA1 positive can receive either

Question 14

dalmations and blood transfusions

Answer 14

• they are Dal negative
• blood transfusions should be from another dalmation or cross-matched

Question 15

blood types in cats

Answer 15

• A, B, AB
• they have naturally occurring alloantibodies in their plasma
• first transfusions can cause reactions
• other types exist

Question 16

neonatal isoerythrolysis in cats

Answer 16

• type B queen has type A or AB kittens

Question 17

what blood should cats be given?

Answer 17

• matched blood type
• if AB blood not available for AB patient, type A is next best
  (weak anti-B antibodies)
• all cats need to be typed even in emergency
• cross-matching necessary in subsequent transfusions

Question 18

cross matching indications

Answer 18

• recipient received transfusion > 4 days ago
• history of transfusion reaction
• transfusion history unknown
• cats
• dalmations
• previous pregnancy

Question 19

cross matching

Answer 19

• looking for agglutination (not compatible)
• determines serological compatibility
• major + minor cross matching

Question 20

major crossmatch

Answer 20

recipients serum and donors red blood cells
- can cause more severe transfusion reaction if incompatible

Question 21

minor crossmatch

Answer 21

donors serum and recipients red blood cells

Question 22

good blood donor requirements

Answer 22

• healthy, between 1-8yrs old
• no history of travel (reduces chance of bloodbourne infectious diseases)
• receiving routine preventative health care
• never received transfusion
• good jugular veins

Question 23

requirements for canine blood donor

Answer 23

• large >25kg
• clear disease screens

Question 24

requirements for feline blood donor

Answer 24

• large >4kg, good body condition score
• must be blood typed
• clear disease screens
• ideally indoor cats

Question 25

volume limits for blood donors

Answer 25

dogs= 15ml/kg
cats= 10-12ml/kg

Question 26

how to give blood transfusion

Answer 26

1. visually inspect bag, gently thaw
2. admin via giving set with filter
3. give 10-20ml/kg
   - 1% increase in PCV for each 2ml/kg whole blood given
4. 1ml/kg/hr for 20 mins to allow early recognition of transfusion reactions
5. give rest over 4-6hrs
6. don’t feed during
7. don’t admin drugs through same catheter

Question 27

types of immunologic transfusion reactions

Answer 27

• antigen-antibody sensitivity reaction
• cytokines from product storage
• allergic/hypersensitivity reaction

Question 28

non-immunologic transfusion reactions

Answer 28

• volume overload
• citrate intoxication
• thrombosis
• ammonia intoxication