Blood Loss and Transfusion Flashcards
what is a blood transfusion?
process of transferring blood or blood-based products from one individual into the circulatory system of another individual of same species
what is the purpose of transfusion
increase Hb content of blood
increase circulating volume
increase plasma albumin content
provide coagulation factors
provide functional platelets
T/F loss of 50% of circulating volume is fatal but the loss of 50% of hemoglobin may not be
True
types of blood products
fresh whole blood (PCV ~40%)
packed red cells (PCV ~70%)
fresh frozen plasma
when should fresh whole blood be used
increase Hb content
acute blood loss and if TP <3.5
when should packed red cells
increase Hb content
if TP > 3.5 g/dL
transfusion trigger values
acute blood loss >20% of blood volume
acute anemia: PCV <20%
chronic anemia: PCV <15%
anemia + anesthesia: PCV <20%
T/F clinical signs are more important than arbitrary trigger values
True
clinical signs of blood loss
pale mm
elevated heart rate
low blood pressue
weak pulse
blood in surgical sponges and suction container
T/F acute blood loss may not chamge PCV and TP
True
equation for estimating blood loss
blood loss (ml) = (PCV of suctioned fluid X vol. in canister (ml))/ preoperative patient PCV
how much blood can a standar surgical sponge contain
5 ml
how much blood should be given in acute blood loss
same amount as lost amount
general rule: 2ml whole blood/kg BW raises PCV by 1% (assuming donor PCV of 40%)
equation for amount of bloof to be transfused
blood to be transfused (ml) = ([PCV required - PCV recipient] x blood volume of recipient (ml)) / PCV of donor
what is the empurical dose for dogs and cats
10-40 mL/kg for dogs
5-20 mL/kg for cats
what is the dosing and rate for transfusions
start with 0.25 ml/kg for first 30min to test for rxn
continue with rate: 5-10 mL/kg/h; faster in emergency
complete transfusion within 4 hours
T/F transfusions should not be mixed with ringers
True
Ca: blood will clot again
T/F FFP is and effective method of increasing plasma albumin content
False
need large volumes for long hours
consider supplementation with concetrated albumin
what is the best option for providing coagulation factors
cryoprecipitate
T/F plasma (fresh or fresh frozen) may trigger allergc reaction
True
trigger immunity against blood group Ag-s (typing is necessary)
what should be given to provide functional platelets
fresh whole blood
plastic container - platelets adhere to glass
transfuse within 8 hours
store at room temp
T/F platelet rich plasma is better than fresh whole blood for replacing platelets but difficult to get in vet med
true
donor selection parameters
free from blood born disease
actual vaccination status
good general physical condition
not too young or too old
middle to large body size
preferable castrated male of nulliparous female
when collecting blood in an open system it should be used within…
12 hours
types of anticoagulants used
CPD
Na citrate
heparin
side effects of transfusions
circulatory overload
transfusion related acute lung injury (TRALI)
citrate induced hypoCa (tetany)
sepsis
transmission of infectious diseases
T/F long term benefits of transfusions are questionable and should only be done when absolutely necessary to save a life
True
acute reaction from blood type incompatibility
life threatening
hemolysis (horses and cattle)
agglutination
blood typing incompatability - slow reaction
decreased life span of RBC (few days)
signs of acute reactions
increased HR and RR, decreased BP, dyspnea
wheals, urticaria, fever
pain at injection site
CV collapse, hemolysis, renal failure, DIC
less signs under anesthesia
tx of acute rxn
stop transfusion
epi IV
antihistamines IV
equine blood groups
type Aa and Qa - most antigenic
typing difficult, cross matching not reliable
no naturally occuring antibodies
what is cross matching
determines serological compatibility between recpient and donor
based on agglutination reaction
major cross match
donor RBCs + recpient plasma
minor cross match
recpient RBC + donor plasma
what is oxyglobin
stabilized bovine hemoglobin
used in tx of anemia in dogs
duration of effect - min 24 hours
may cause circulatory overload
