Exam 1 - Transfusion Medicine

Question 1

how are blood groups defined?

Answer 1

defined by the inherited antigens on the surface of the red blood cell that are SPECIES SPECIFIC & vary in immunogenicity & clinical significance

important to know for immunologic transfusion reactions!

Question 2

what are the most significant blood types in dogs?

Answer 2

dog erythrocyte antigen 0 DEA 1.1 & DEA 1.2

Question 3

what dog blood type is extremely antigen?

Answer 3

DEA 1.1

Question 4

how many blood group types are recognized in canines?

Answer 4

7+

Question 5

what is the Dal part of canine blood types?

Answer 5

separate antigen with no correlation to known DEA antigens - needs further investigation to determine its significance

Question 6

do you expect a transfusion reaction if you give a recipient DEA 1.1+ dog donor DEA 1.1+ blood?

Answer 6

no response

Question 7

do you expect a transfusion reaction if you give a recipient DEA 1.1+ dog donor DEA 1.1- blood?

Answer 7

nope

Question 8

do you expect a transfusion reaction if you give a recipient DEA 1.11 dog donor DEA 1.1+ blood?

Answer 8

YES - antibody formation!!!!!!

Question 9

do you expect a transfusion reaction if you give a recipient DEA 1.1- dog donor DEA 1.1- blood?

Answer 9

no response

Question 10

what are the blood types we see in cats?

Answer 10

type A, type B, & type AB

Question 11

what cat blood type do you have to be careful with blood transfusions?

Answer 11

type B cats have a strong, potentially fatal reaction to type A donors

Question 12

what is the MiK antigen in cat blood types?

Answer 12

newly discovered antigen independent of the AB system that may contribute to hemolytic reactions in typed patients

Question 13

what antibodies do cats with type A (A antigen) blood have?

Answer 13

anti-B antibody

Question 14

what antibodies do cats with type B (B antigen) blood have?

Answer 14

anti-A antibody

Question 15

what is the desirable donor blood type of horses? why?

Answer 15

AaCa - most common blood type & less likely to have circulating antibodies

Question 16

T/F: a small percentage of horses have naturally occurring antibodies making them a poor donor

Answer 16

true

Question 17

what is the donkey factor?

Answer 17

auto-antibody present in many horses so donkeys shouldn’t receive horse plasma unless they are pre-screened!!!

Question 18

for large animal blood transfusions, which animals are compatible & which aren’t?

Answer 18

alpacas & llamas are COMPATIBLE

sheep & goats are NOT compatible

pigs are only compatible with pigs

Question 19

what situations should blood typing be done for companion animals?

Answer 19

recommended for all canine & feline patient red cell transfusions & plasma cell transfusions for cats

Question 20

what do blood typing tests look for?

Answer 20

visible hemagluttination reaction between patient RBC antigens & a known reagent antisera

Question 21

what bed-side blood typing tests are available for companion animals?

Answer 21

canine DEA 1.1 & feline type A, type B, & type AB

Question 22

why do we use blood typing in horses?

Answer 22

used to select donors - want AaCa with no alloantibodies

also used to screen mares for NI 30 days before parturition

Question 23

what is a major cross match? how is it done?

Answer 23

major cross match is used for detecting antibodies in recipient plasma

mix the donor RBC with recipient plasma & evaluate for agglutination

Question 24

what is a minor cross match? how is it done?

Answer 24

minor cross match is used to detect antibodies in donor plasma

you mix the donor plasma with the recipient RBC & evaluate for agglutination

Question 25

how is cross matching done in horses?

Answer 25

same as companion animals but you also check for hemolysins by adding the complement - one commercially available equine cross match kit

Question 26

what blood typing do we do for ruminants? why?

Answer 26

don't routinely type the donor, but ideally the donors would be j-factor negative

Question 27

T/F: usually, ruminants get one 'free' transfusion before sensitization occurs

Answer 27

true - subsequent transfusions may be more rapidly broken down

Question 28

when is cross-matching recommended prior to giving a blood transfusion?

Answer 28

patient has an unknown transfusion history patient has had a hemolytic reaction on a prior transfusion regardless of a time lapse more than 3 days since prior transfusion if the patient is a donkey, mule, or hinny recipient horse that is known AaQa negative - they are more likely to have naturally occurring alloantibodies

Question 29

when doing a whole blood transfusion, what happens to the blood collected after 24 hours?

Answer 29

loss of coagulation factors & platelets

Question 30

how long do anticoagulant products last when collecting whole blood?

Answer 30

sodium citrate - 24 hours ACD - 3 weeks CPDA - 5 weeks

Question 31

what receptacle is best used when collecting blood from a donor animal for a transfusion?

Answer 31

plastic bags are better than glass bottles because glass will activate platelets

Question 32

what is the effect of storage on whole blood products?

Answer 32

decreased oxygen release to tissues because of decreased 2-3 DPG (significant after 10 days of storage) 2-3 DPG can take 4-24 hours to be restored hyperkalemia

Question 33

how much blood can a donor horse give?

Answer 33

20ml/kg every 3 weeks

Question 34

if you are considering doing a blood transfusion for a horse in acute need, what parameters are you looking at?

Answer 34

clinical signs & lactate (NOT PCV/TP!!!!!!!)

Question 35

how much blood do you give to a horse with a chronic illness for a transfusion?

Answer 35

0.08 X BWkg X [(PCV desired - PCV recipient)/(PCV donor)

Question 36

when are packed red blood cells indicated for a transfusion?

Answer 36

treatment of anemia - deficiency of red blood cells or hemoglobin (anemia may be well-tolerated, acute vs. chronic)

Question 37

T/F: no transfusion trigger has been identified in veterinary medicine

Answer 37

true

Question 38

what are the different formulas used for dosing packed red blood cells for transfusions in dogs?

Answer 38

volume administered = 90 ml/kg X BWkg X [(desired PCV - actual PCV)/(donor PCV)] volume administered = 1.5mL X desired % increase in PCV X BWkg 10-20 ml/kg

Question 39

what are your options to wash RBC for foals with neonatal isoerythrolysis?

Answer 39

cell saver, centrifuge, & sedimentation

Question 40

what blood product should you use for a foal with neonatal isoerythrolysis?

Answer 40

use the DAM RBC - washed red blood cells

Question 41

why do we see a decrease in regeneration in an animal that received a blood transfusion?

Answer 41

if you give them enough blood to restore their normal PCV, this decreases their own regenerative response

Question 42

T/F: donor RBCs will have a shorter life span

Answer 42

true

Question 43

T/F: increased volumes used for transfusions are associated with a greater potential for transfusion reactions

Answer 43

true

Question 44

what is the dose used for plasma transfusions?

Answer 44

10-20 ml/kg

Question 45

how long can plasma be stored as a blood product?

Answer 45

stored for 1 year & can be thawed & re-frozen within 1 hours

Question 46

how is fresh frozen plasma collected?

Answer 46

removed from the RBC & frozen within 24 hours - contains therapeutic levels of labile & non-labile factors

Question 47

what is the most common indication of plasma transfusions for horses? what are some other examples of times you would give it?

Answer 47

failure of passive transfer in the neonate (foal) boutique plasma in farms with endemic diseases - plasma containing r. equii antibodies administration of boutique plasma in specific disease - west nile & botulism enterocolitis with protein loss - palliative measure

Question 48

what are some indications for a platelet transfusion?

Answer 48

<10,000 platelets <20,000 with active bleeding <50,000 with a planned invasive procedure documented thrombocytopathia

Question 49

what is an autotransfusion?

Answer 49

collecting autologous blood from a cavity, filtering it, & returning it to the patient's vascular space

Question 50

T/F: transfusion reactions are uncommon in horses & ruminants

Answer 50

true

Question 51

when do we see transfusion reactions in dogs?

Answer 51

3.3-13% in dogs receiving pRBCs or fresh whole blood we use conservative or restrictive methods have been documented to decrease incidence of reactions

Question 52

what is the most common immunologic transfusion reaction seen?

Answer 52

non-hemolytic febrile reaction followed by hemolytic reactions

Question 53

why do non-hemolytic febrile transfusion reactions occur? what is it defined as? what do you do for your patient if it happens?

Answer 53

result of proteins & WBCs in unit - increase in patient's temperature by 1°C, but typically self-limiting discontinue transfusion & wait for resolution & then restart the transfusion at a slower rate

Question 54

why do hemolytic transfusion reactions occur? what is it defined as? what do you do for your patient if it happens?

Answer 54

incompatibility with RBC - patient develops hemoglobinemia, hemoglobinuria, & shock discontinue transfusion & cross-match the patient to a new unit

Question 55

animals with kind of disease have a greater risk for transfusion reactions?

Answer 55

patients with immune-mediated disease

Question 56

what was the effect of premedication for patients receiving a blood transfusion?

Answer 56

administration of diphenhydramine and/or corticosteroid did not decrease occurrence - but diphenhydramine did reduce the occurrence of type I hypersensitivity reactions (allergic)

Question 57

what premedication is used for horses before a blood transfusion? is there any risks associated with this?

Answer 57

horses & foals - flunixin meglumine often given nephrotoxicity from flunixin is a concern

Question 58

what monitoring is done during transfusions?

Answer 58

temperature, heart rate, & respiratory rate taken every 10 minutes for the first 30 minutes & then at every hour starting at an hour until the transfusion is finished

Question 59

what is the maximum rate of a transfusion?

Answer 59

total volume to be given / 3.4125

Question 60

what is the transfusion rate you use for the first 20 minutes? what about the following 40 minutes?

Answer 60

max rate / 4 max rate / 2

Question 61

what is the target amount of time you should aim for when doing a blood transfusion?

Answer 61

done over 4 hours

Question 62

what can you do for anemic puppies & kittens?

Answer 62

they typically are anemic due to intestinal parasites - bitch or queen are excellent donors, but for sure type the queen & kittens

Question 63

T/F: in horses, you can easily sediment & remove red blood cells by letting a bag hang for 3-4 hours

Answer 63

true - acid-citrate dextrose bags appropriate for storage from 21-28 days

Question 64

when would you see an immediate transfusion reaction in a cat in regards to giving specific blood types?

Answer 64

doing a major cross match & the donor has A antigens & the recipient is type B & has B antigens & will immediately form anti-A antibodies

Question 65

in doing a minor cross match, when would you see an immediate transfusion reaction in cat blood types?

Answer 65

donor has a-antigens & anti-b antibodies & the recipient is a type B cat

Question 66

why may an animal have a delayed reaction on the next blood transfusion?

Answer 66

the first transfusion the animal becomes sensitized & forms antibodies