Blood transfusions

Question 1

why are blood transfusions done?

Answer 1

for trauma/blood loss, immune mediated diseases, chronic renal failure, coagulation issues

Question 2

what can be transfused?

Answer 2

fresh whole blood, packed red blood cells, fresh frozen plasma, cryoprecipitate, cryosupernatant, platelet rich plasma

Question 3

what tests do we do before transfusions?

Answer 3

blood typing and crossmatching to determine if donor and recipient are compatible (survival of transfused red blood cells can’t be guaranteed in recipient’s circulation)

Question 4

who do you do blood typing and crossmatching tests on?

Answer 4

donor and recipient

Question 5

how are canine blood types numbered?

Answer 5

according to dog erythrocyte antigen (DEA) system
DEA 1 = most antigenic, most severe reactions
DEA 1.1 positive and DEA 1.1 negative are the most transfused types

Question 6

what is the most common blood type in dogs?

Answer 6

DEA 4 positive
97-99% of dogs have this blood type

Question 7

what is the newly discovered canine blood type?

Answer 7

Dal
found in 11% of Dalmatians, 43% of Dobermans, and 57% of shih tzus
originally discovered in a Dalmation

Question 8

what is the most common myth about canine transfusions?

Answer 8

the first transfusion is free
dogs don’t have naturally occurring alloantibodies but they can develop antibodies to the antigens ~ 4 days after transfusion and may have a delayed reaction

Question 9

feline blood types

Answer 9

AB blood group is most widely recognized
includes A, B, AB, mik
type A: 99% of cats
type B: ~ 1% of cats
type AB: < 1% of cats (usually Turkish vans and Devon Rexs)

Question 10

alloantibodies

Answer 10

immune antibodies that are only produced after exposure to foreign red blood cell antigens

Question 11

cats and alloantibodies

Answer 11

they can produce alloantibodies to all red blood cell antigens they lack and are naturally occurring (unlike dogs)

Question 12

what are the different cat blood types and their antibodies?

Answer 12

type B: have strong anti-type A antibodies (can cause fatal reaction with as little as 1 mL of blood)
type A: have weak anti-type B antibodies
type AB: have neither antibodies

Question 13

mik blood type

Answer 13

newly discovered blood type in cats when incompatibilities were found in a donor named Mike

Question 14

blood typing

Answer 14

look for red blood cell antigens
dogs and cats don’t have naturally occurring alloantibodies to the antigens that they don’t have

Question 15

blood typing kits

Answer 15

card based agglutination tests or immunochromatography assays

Question 16

crossmatching

Answer 16

detects serologic incompatibility by identifying antibodies present in the recipient’s plasma against a donor’s red blood cell antigens or vice versa

Question 17

what are the 2 types of crossmatching?

Answer 17

major: mixing the recipient’s plasma with the donor’s red blood cells
minor: mixing the donor’s plasma with the recipient’s red blood cells
reactions are indicated by hemolysis, agglutination, or both in crossmatching

Question 18

good canine donor

Answer 18

age: 1-8 years (best younger)
weight: 23 kg for 450 mL or 13 kg for 250 mL
up to date on vaccines
blood typing performed and full labs
screened for infectious diseases: Rickettsial diseases, babesia, brucellosis, bartonella, mycoplasma, heartworm

Question 19

poor canine donors

Answer 19

on medication, heart murmur or cardiac disease, seizures/seizure-like activity, heartworm disease or unknown, chronic illness, in heat (hormones and bleeding), anxious/fearful (cortisol in blood)

Question 20

good feline donors

Answer 20

age: 1-8 years (best younger)
weight: at least 10 lbs (4.5 kg)
up to date on vaccines
indoor only
screened for infectious diseases (FeLV, FIV, intestinal parasites, heartworm)
thyroid tested and urinalysis done

Question 21

how much can a dog/cat donate?

Answer 21

dog: 80 mL/kg x BW (kg)
cat: 70 mL/kg x BW (kg)
can donate up to 10% of their blood

Question 22

fresh whole blood dog collection

Answer 22

sedate if necessary
prep site: jugular
obtain FWB (fresh whole blood) using collection set (kits available in various sizes: 10-20 mL/kg)
use within 8 hours
replace fluid loss with IV or SQ fluids

Question 23

closed collection system

Answer 23

used for dogs
contains a single use main collection bag with anticoagulant solution, tubing, and a 16G needle

Question 24

fresh whole blood feline collection

Answer 24

sedate if needed
prep site: jugular
obtain FWB using heparinized 60mL syringe (use 5-10 units of Heparin/mL)
use within 8 hours
replace fluid loss with IV or SQ fluids

Question 25

open collection system

Answer 25

done through syringe collection
used for cats since collection bags are too big
19/21G butterfly catheter attached to a 3-way stopcock and a sterile 10-30mL syringe containing an anticoagulant, mix blood in the syringe as its collected, transfer from syringe into a sterile empty bag or transfer pack for easy delivery

Question 26

A-C-D vacuum bottle

Answer 26

don’t use!!!!
used to be a method of collection but the glass of the bottle starts the clotting cascade and it collects blood fast which causes foam buildup

Question 27

collection tubing

Answer 27

has a filter within the drip chamber or as a component in the line that is designed to filter out clots that might form despite anticoagulation but it doesn’t filter out microorangisms or bacteria

Question 28

autotransfusion

Answer 28

blood is collected from patient and re-transfused
decreases risk of reactions
good for trauma patients with blood pooling in a cavity
contraindications: septic effusion and neoplasia

Question 29

patient monitoring

Answer 29

check vitals every 10-15 minutes for the 1st hour (TPR, mentation, note any vomiting or diarrhea)
PCV checks can be helpful to determine if hemolytic reactions are happening
reactions can be acute or delayed, and immunologic (hemolytic) or non-immunologic (non-hemolytic)

Question 30

hemolytic acute and delayed reactions

Answer 30

acute: occurs within 30-60 min
symptoms: recumbency, tachycardia, distress, tachypnea, hypotension, bradycardia, pulmonary edema, vomiting, diarrhea, tremors, hypersalivation, death
delayed: may not be seen until 48 hours after transfusion
symptoms: juandice, fever, anorexia, hemoglobinuria, slow decrease in PCV over the course of a few days

Question 31

non-hemolytic reaction

Answer 31

caused by antibodies to platelets, white blood cells, or plasma proteins
often manifest as: angioedema, urticaria, pruritis, vomiting, diarrhea, fever
usually resolve by stopping transfusion and giving antihistamines or sometimes steroids
can cause anaphylaxis or shock

Question 32

non-immunologic reactions

Answer 32

arise from physiological consequences of blood component contents and infectious agents
hemolysis can be caused by red blood cell trauma due to overheating product, freezing product, mixing RBC product with other fluids causing cellular damage, warming then refrigerating product, collecting or infusing through small needles

Question 33

transfusion-associated circulatory overload (TACO)

Answer 33

most common non-immunologic transfusion reaction
blood products add volume to circulatory system and increase BP
results in pulmonary edema in cardiac patients

Question 34

other non-immunologic reactions

Answer 34

bacterial pyrogens and sepsis: patients will mount a febrile response within 15-20 mins from transfusion start
citrate intoxication: causes hypocalcemia
hypothermia