Approach to Therapeutics in Small Animal Hematopoietic Cases Flashcards
what are the components of blood and what are the products that can be made out of each
what are the types of blood products (5)
- fresh whole blood
- whole blood
- packed red blood cells (PRBC)
- fresh frozen plasma (FFP)
- frozen plasma (FP)
what does fresh whole blood contain (5)
- RBCs
- platelets
- WBCs
- plasma proteins
- all clotting factors
what does whole blood contain (3)
- RBC
- plasma proteins
- stable clotting factors
what does packed red blood cells contain
RBCs
what does fresh frozen plasma contain (3)
- all clotting factors
- vWF
- plasma proteins
what does frozen plasma contain (2)
- plasma proteins
- vitamin K dependent clotting factors (II, VII, IX and X)
what are the uses of fresh whole blood
- anemia (hemorrhage)
- thrombocytopenia
- pacytopenia
what are the uses of whole blood
- anemia (hemorrhage)
what are the uses of packed red blood cells (PRBC)
anemia (hemolysis, non-regenerative anemia, chronic blood loss)
what are the uses of fresh frozen plasma
coagulopathies (esp with liver disease, factor VIII deficiency, vWD)
what are the uses fo frozen plasma
coagulopathies of non-liable clotting factors (anti-coagulant rodent toxicity)
after you remove packed red cells from the fridge how long do you have before they go bad
4 hours
what cautions need to be taken when giving cats transfusions
- fresh whole blood only
- prone to volume overload
what are the canine blood groups
DEA (dog erythrocyte antigen) groups: 1.1, 1.2, 3, 4, 5, 6, 7, & 8 (DAL)
do dogs have alloantibodies
no naturally occuring ones
can you give a dog an unmatched donor
yes if it is their first transfusion ever
first transfusions rarely result in reactions
what needs to be done after a dog has had a previous transfusion
cross match prior to subsequent transfusions or unknown history
what blood type are greyhounds and GSDs usually
DEA 1.1 and 1.2 negative
very useful donors
what are the feline blood groups
A, B and AB
MIK antigen
what blood type is most common in felines
A
what is the rarest blood type in felines
AB
do cats have naturally occuring alloantibodies
yes
do cats need to be blood typed for their first transfusion
yes
what blood type is the most safe to transfuse to a blood type AB cat
type AB
what blood type is the most safe to give to a blood type A cat
type A
B and AB will have a reaction
what blood type is the most safe to give to a blood type B cat
B only
A and AB will result in fatal reaction
what is the purpose of blood typing (3)
- minimize risk of reaction
- avoid formation of alloantibodies in future
- breed blood types not a rule
how can you blood type
in house tests available (rapidvet)
what is crossmatching
identifies reactions between the donor blood and the recipient blood using agglutination or hemolysis
when is it difficult to crossmatch
cases with autoagglutination cannot be easily type or cross matched
when should you cross match blood in dogs
- previous transfusion >4 days
- unknown transfusion history
- history of transfusion
- previous pregnancy
when should you cross match a cat
every transfusion?
test for MIK antigen
how do you decide whether or not an animal needs a transfusion
based on clinical signs
no PCV value that gives indication
chronic vs acute situations differ: chronic anemia tends to compensate more for anemia, acute trauma that is loosing blood but may have normal PCV because it hasn’t had time to drop yet
can you raise the number of platelets with a blood transfusion
No it isnt possible to increase the platelet numbers with currently available transfusion fluids
but fresh whole blood –> can provide enough platelets to stop active hemorrhage (more beneficial than using stored whole blood)
what are the benefits from obtaining blood products from a bank
- allows donor screening/typing
- convenient for donor
- increased availability for the patient
- products are tailored to individual needs
what are the conditions for canine blood donation (8)
- 1-8 years old
- over 25kg
- fully vaccinated and wormed (lung worms too)
- healthy and not receiving any medication
- never travelled outside UK
- not received a transfusion previously
- never had puppies and is not pregnant
- has a good temperament
if sedation is needed to collect blood from a donor dog what could you use
butorphanol
what is the max amount a canine can donate
18ml/kg every 8 weeks
what are the conditions for feline blood donors (9)
- over 4 kg
- fully vaccinated and wormed
- healthy and not receiving any medication
- FIV/FeLV negative
- mycoplasma felis PCR negative
- never travelled outside UK
- has not recieved a transfusion previously
- has never had kittens and is not pregnant
- has a good temperament
what is crucial when collecting blood for donation
anticoaglulant/blood ratio
too much AC –> citrate toxicity –> citrate binds calcium –> hypocalcemia leading to cramps, seizures, respiratory arrest
how is blood administered
peripheral vein via an IV catheter (>22 gauge if possible)
infusion pumps (check if able to use blood products)
blood giving set filter
no medications/solutions should be given through same tubing (except 0.9% NaCl or plasma)
given within 4 hours
educate owners
can you administer IVFT concurrently with blood products
lactated ringer’s solution through the same line as the blood shoul dbe avoided because calcium within the fluid precipitates with anticoagulants present in WB and pRBCs
unless they are extremely hypovolemic, blood admin should be adequate fluid therapy
what is the formula used to determine required volume of blood
k x body weight x (desired PCV - recipient PCV)/donor PCV
k = 90 for dogs
k = 60 for cats
2ml/kg donor blood will raise recipient PCV 1%
2ml pRBCs raise recipient PCV by 2%
how much blood does a 10kg dog require
the donor PCV is 70%
required volume of blood = 90 x 10kg x (25% desired PCV - 10 recipient PCV)/70 (pRBCs) donor PCV
= 90 x 10 x 15/70
= 193 mls
how do you calculate the rate at which to give blood
take into account the condition of the patient
what is the transfusion rate in the first 15-30 mins
first 15-30 mins: 0.5-2 ml/kg/hr
what is the transfusion rate if you have a normovolemic and no reaction
normovolemic and no reaction: 5-10 mls/kg/hr
what is the transfusion rate in a compromised heart/kidney function patient
compromised heart/kidney: 4 ml/kg/hr MAX
what is the transfusion rate for a hypovolemic and no reaction patient
hypovolemic and no reaction: 20ml/kg/hr
what is the maximum volume of transfusion
22ml/kg
what are immunological transfusion reactions that can occur
hemolytic: acute (Ag-Ab complex formation) or delayed (2-21 days after)
what are non-immunological transfusion reactions
- too rapid infusion rate
- volume overload
- microbial contamination
- thrombosis
- air embolus, TRALI
what are signs of a tranfusion reactions (11)
- tachycardia or bradycardia
2 dyspnea, tachypnea or coughing
- pyrexia
- depression
- vocalizing
- vomiting
- urticaria, erythema, pruritus (anaphylactic reactions)
- shcok
- tremors and convulsions
- cardiopulmonary arrest
- jaundice, hemoglobinuria, anorexia (delayed)
how do you treat transfusion reactions
- stop transfusion immediately
- monitor patient
- oxygen +/- artifical ventilation
- adrenaline IV
- IV fluids
- antihistamines (piriton) and H2 blockers
- dexamethasone
- anti-emetics
