haematological emergencies Flashcards
what is acute hemolytic transfusion reaction ?
acute intravascular hemolysis due to ABO blood group incompatibility
what is the presentation with acute hemolytic transfusion reaction ?
chest pain
shortness of breath
back pain
fever
tachycardia
orr shock
what are the complications of acute hemolytic transfusion reaction ?
1- acute renal failure
2- disseminated intravascular coagulopathy (DIC)
3- cardiovascular collapse and death
what is the management for acute hemolytic transfusion reaction ?
1.stop the transfusion immediately
2.give IV fluids
3.if there is hemolysis give loop diuretics
4. if there is refractory hypotension use IV vasopressors
what are the labs used to check for hemolysis ?
send a peripheral smear CBC
LDH is high in hemolysis
haptoglobin is low in hemolysis
indirect bilirubin is high
direct coombs test
check creatinine
check urine
coagulation profile
what happens in type 1 hypersensitivity reaction after blood transfusion ?
patient presents with hives and pruritus without fever , bronchospasm or shock
what is the management for type 1 hypersensitivity reaction to blood transfusion ?
stop the transfusion
give epinephrine
corticosteroids
bronchodilators
IV fluids
supplementary oxygen
how can we protect against anaphylaxis ?
IgA deficient donors blood is available
washed cells are also preferred
what is the most common type of transfusion related reaction ?
simple febrile reaction
how does the simple febrile reaction happen ?
recipients antibody reacts to the donors leukocytes
what is the difference in presentation between simple febrile reaction and anaphylaxis ?
simple febrile reaction the patient presents with fever with no urticaria no bronchospasm no shock
how do we avoid simple febrile reactions ?
leukoreduction of the transferred component
what is the management for simple febrile reactions ?
slow down the transfusion and give paracetamol
what is the presentation of transfusion associated acute lung injury ?
non cardiogenic pulmonary oedema
can cause ARDS
what antibody is associated with TRALI ?
anti HLA
when does TRALII most commonly happen ?
after plasma transfusion but any plasma containing product can cause it
what is the management of TRALI ?
1- supplemental oxygen and ventilation
2- central line should be placed for haemodynamic support just in case there is hypotension
what is the management of TRALI ?
diuretics if the cause is CHF
what is delayed transfusion reaction ?
exaggerated response to a foreign red cell antigen
presents 5 days to a week post transfusion
patient presents with jaundice, anemia and fever
what are the triggers for DIC ?
severe sepsis or infection
solid malignancies
pregnancy
haematological malignancies
APL
what are the two types of DIC ?
overt ( decompensated) and non overt (early )
what are the differential diagnosis of DIC ?
1- hepatic cirrhosis
2- HUS and TTP
3- pregnancy related thrombocytopenia
HELLP
4- heparin induced thrombocytopenia
what is the treatment approach for DIC ?
generally - treat the underlying condition
if asymptomatic and only lab evidence - give LMWH
if there is thromboembolism - LMWH
if there is bleeding - LMWH
what is the normal platelet count ?
150 - 450
when are schistocytes seen on blood film ?
in cases of thrombotic microangiopathies
like HUS and TTP
what are the different types of microangiopathic hemolytic anemias ?
HUS
TTP
DIC
what is the etiology inn TTP ?
in thrombotic thrombocytopenic purpura there is a deficiency in the ADAMST13 enzyme
what are the lab findings associated with TTP ?
low platelet count
PT and PTT are unaffected
schistocytes
elevated LDH
elevated Bilirubin
low haptoglobin
negative coombs
raised reticulocyte count
what is the function of ADAMST13 enzyme ?
degrades vWF multimers into monomers
the inability to break these multimers increases the likelihood of the formation of platelet thrombosis
what is the management of TTP ?
emergency plasma ecxchange plus frresh frozen nplasma
steroids
what is contraindicated in the treatment of TTP ?
platelet transfusion
what is the characteristic pentad of TTP ?
MAHA
acute renal failure
thrombocytopenia
fever
neurological abnormalities
how can you differentiate between HUS and TTP ?
there are more prominent neurological features in TTP than with HUS
also TTP presents with fever
distinction test is with ADAMST13
what level of ADAMST13 can we diagnose TTP and exclude HUS ?
below 10 is usually diagnostic for TTP