Transfusion Flashcards
what are the 4 indications for transfusion
- anemia
- secondary coagulopathy
- thrombocytopenia
- hypoproteinemia (rare)
transfusing specific components vs whole blood
only want to transfuse the products that the patient needs
- packed RBCs
- platelets
- plasma
RBC transfusion indication
anemia
transfusion triggers for RBCs
- PCV = 20-22%
- ongoing losses (transfuse sooner)
- chronicity
- clinical response to anemia (transfuse later if patient compensating)
- underlying/concurrent disease
RBC products
- fresh whole blood
- stored whole blood
- packed RBCs
transfusion volume - RBCs
goal: PCV = 25%
pRBCs: 1-1.5 mL/kg
whole blood: 2 mL/kg
(to increase PCV by 1%)
indications for plasma transfusion
- acquired secondary coagulopathy w/ serious bleeding (rodenticide, liver failure, heat stroke, DIC)
- bleeding w/ congenital coagulopathy
- clinical signs of secondary coagulopathy
- coagulation testing - prolonged PT/PTT, ACT, etc
products for transfusing plasma
- fresh plasma: all factors
- fresh frozen plasma: all factors
- frozen plasma: stable factors (vit K dependent)
- cryoprecipitate: labile factors
transfusion volume - plasma
10-15 mL/kg minimum
titrate to effect
indications for platelet transfusion
- severe thrombocytopenia w/ severe hemorrhage (<10,000)
- moderate thrombocytopenia w/ planned invasive procedure (>50,000)
- massive transfusions
- thrombocytopathy
platelet transfusion products
SHORT half life
- fresh whole blood
- platelet rich plasma
- platelet concentrate
- cryopreserved platelets
transfusion volume - platelets
1 unit/kg
titrate to effect
is it common to transfuse albumin?
no
what is blood type determined by
antigens present on RBC surface
genetically determined
species specific
antigenic in individuals that lack the same marker
what is the major dog blood type antigen
DEA-1
strongly antigenic
generates a strong alloantibody response AFTER sensitization
do dogs have naturally occurring antibodies against DEA-1
NO
DEA-1 negative dogs do NOT have natural antibodies against DEA-1
will develop antibodies AFTER sensitization (ex. previous transfusion with DEA-1 blood)
DEA-1 negative donors and recipients
donate to DEA-1 + and -
receive from DEA-1 - only
DEA-1 positive donors and recipients
donate to DEA-1 + only
receive from DEA-1 + and -
when is crossmatching required for dogs
if transfusion has occurred > 3 days ago
OR
unknown history
recommended but not required for first transfusion
what are the cat blood typing antigens
AB blood groups
MiK antigen
type A cat blood
majority of DSH/DLH and non-pedigree cats
has WEAK anti-B natural antibodies
type A donors and recipients
donate to A and AB
receive from A only
type B cat blood
has STRONG anti-A antibodies
type B donors and recipients
donate to B only
receive from B only
what happens if type A blood is donated to a type B cat
marked hemolysis
B recipient has strong anti-A antibodies
what happens if type B blood is donated to a type A cat
minor hemolytic reaction
A recipient has weak anti-B antibodies
type AB cat blood
rare - certain purebred cats only
has type A and B antigen
NO naturally occurring antibodies
type AB donors and recipients
donate to AB only
receive from A only
B blood will have a strong reaction against the A antigen
when is crossmatching required for cats
ALL transfusions due to naturally occurring antibodies
and because MiK is not determined on blood typing - should cross match
blood typing
identifies the primary red cell surface antigen of the donor and recipient
crossmatching
identifies any blood group abnormalities beyond the single surface antigen
major: tests for antibodies in the recipient plasma against donor RBCS
minor: tests for antibodies in the donor plasma against recipient RBCs
what to do in emergency situation (dogs and cats) if you do not have time to crossmatch
dogs: type OR give DEA-1 neg pRBCs
cats: type or watch for agglutination on slide
- if only A blood available - give anyway if patient will die without transfusion
acute transfusion reactions
occurs within 24 hours of transfusion
delayed transfusion reactions
occurs after 24 hours of transfusion
febrile non hemolytic transfusion reaction (FNHTR)
increase in temperature with NO other clinical signs of reaction
- T > 39C (102.5F) and increase in temp >1C or 1.8F
MOST COMMON
FNHTR pathogenesis and treatment
reaction to WBC or platelet antigen-antibody reactions NOT a reaction to the RBC antigen
tx: slow or stop transfusion and rule out other causes of fever - can restart
acute hemolytic transfusion reaction (AHTR)
type II hypersensitivity reaction in which the recipient antibodies react with donor RBC antigen –> ACUTE LYSIS of transfused cells
leads to CV collapse, hemoglobinemia/uria, fever
delayed hemolytic transfusion reaction (DHTR)
low levels or delayed production of antibodies causing a hemolytic reaction >24 hours after transfusion (slow hemolysis)
not common
allergic reactions
type I hypersensitivity reaction to foreign proteins in blood
CS: urticaria, pruritus, swelling, GI signs, anaphylaxis
TX: slow or stop transfusion, diphenhydramine, epinephrine
do NOT give corticosteroids
transfusion associated circulatory overload (TACO)
respiratory reaction
volume overload leads to hydrostatic pulmonary edema within 6 hours of transfusion
tx: O2 supplementation, ventilatory support, furosemide
how to administer transfusion
use a filter on administration set
rate:
1. first 15 min: 2.5 mL/kg/hr
2. end goal: 5 mL/kg/hr
transfusion monitoring
temperature
HR
RR
mentation
PCV +/- coags PRN
are predmedications indicated to prevent allergic reactions
NO
