Blood Transfusion Flashcards
what is lecuodepletion
removal of white blood cells from blood before transfusion
after lecuodepletion what happens to the blood
centrifuged to RBC, platelets and plasma
what happens to separated plasma before transfusion
frozen - cryoprecipitate
fractioned to from, factor concentrates, albumin, immunoglobulins
what is the normal amount of RBC amount tin males compared to females
male - 130-180 g/L
female - 115 - 165 g/L
what is the transfusion time of blood and what affects the speed
1.5-3 hours - warmer the blood the faster the transfusion
what are the RBC’s stored with to keep it healthy
electrolytes, glucose, adenine
how much does 1 unit of blood raise the haematocrit
1 unit raise Hb by 10g/L
which situations would you use a blood transfusion
significant bleeding, acute anaemia,
when would you want to avoid transfusion
patients with chronic anaemia due to iron deficiency or vitamin deficiencies
what is the normal blood platelet volume
150-450 x 10^9/ L
what is the storage volume and transfusion time for platelets
250-350 ml about 30 minutes
what are the two ways to collect platelets
pooled - 4-6 donors pooled together to from therapeutic dose
aphaeresis - blood cycled through aphaeresis machine - only platelets removed from blood and then return to donor (reduces infection risk)
what is the risk of platelet transfusion
infection risk from arm and storage pooling
when would you do a platelet transfusion and when should you avoid it
prevent and treat bleeding in patient with thrombocytopenia or platelet dysfunction
avoid with: immune/thromboctic purpura or heparin induced thrombocytopenia
what is good about frozen plasma and what is the therapeutic dose
contains all clotting factors but levels V and VIII diminished after 6 hours of thawing
12-15 MI/Kg
when would you give fresh frozen plasma and when would you avoid
significant bleeding gin patients with abnormal clotting
avoid with single factor deficiencies or to reverse warfarin
what do you use to reverse warfarin effects
prothrombin complex concentrate (factor IX complex)
high conc of vit k dependant factors
which factors are vit k dependant and can reverse warfarin
2, 7, 9, 10
what is cryoprecipitate and what is it used for
one does 6-10 units
extracted from FFP - has fibrinogen, vWF, VIII, XIII
used as source of fibrinogen in acquired coagulopathies
what are the acute risks of transfusions
acute < 24 h
immunological - anaphylaxis, acute haemolytic transfusion reaction, TRALI (transfusion - related acute lung injury)
non-immunological - bacterial contamination, TACO (transfusion associated circulatory overload), FNHTR (febrile non-haemolytic transfusion reaction)
what are the delayed risks of transfusions
immunological - delayed haemolytic reaction, post transfusion purpura
iron overload
what are the most common reactions from transfusions
allergic
FNHTR - febrile non-haemolytic transfusion reaction
what is FNHTR and what’s the cause
febrile non-haemolytic transfusion reaction
rise in temp, tachycardia, resolves after disuse
cytokines or other bio molecules
what is TACO
transfusion-associated circulatory overload
acute left ventricular failure with pulmonary oedema
24h after transfusion
what is the most common cause of transfusion related deaths
TACO
what happens if there’s transfusion with bacterial contaminated components
onset in 15 mins
fatal 35% of the time
rigours, high fever
confirm with blood culture
what cause acute haemolytic reaction in transfusions
most often ABO mismatch - recipient has pre-formed antibodies against antigens expressed on the transfused RBC’s
what are the signs and symptoms of acute haemolytic reaction
fever, back pain, DIC
describe pre-transfusion testing of patients
determination of ABO and Rh(D) - crossmatching
check if there is an agglutination
what causes delayed haemolytic reaction
post transfusion formation of new immune IgG antibodies against RBC other than ABO
what are the features and testing for delayed haemolytic reaction
fatigue, jaundice
direct anti-globin test to detect antibodies bound on RBC’s - coombs test
what is coombs test used for
delayed haemolytic reaction
what are the clinical features of allergic responses to transfusion
rash, urticaria, pruritic, periorbital oedema
anaphylaxis - especially with IgA and anti-IgA are at higher risk
what is TRALI
transfusion-related acute lung injury
immune mediated reaction due to antibodies against leucocytes causing leaky pulmonary capillaries
what are the features of TRALI
hypoxaemia, no evidence of volume overload
