Haematology Flashcards
ITP definition?
Immune-mediated reduction in the platelet count. Antibodies are directed against the glycoprotein IIb/IIIa or Ib-V-IX complex.
ITP in children vs. adults?
- Children = acute post infection/vaccination
- Adults = chronic
ITP presentation?
- Incidentally following routine bloods
- Symptomatic = petechiae, purpura, bleeding, catastrophic bleeding uncommon
ITP Rx?
- Oral prednisolone
- IVIG (raises plts quickly, use if active bleeding or urgent invasive procedure)
- Splenectomy rarely
Evan’s syndrome?
ITP + AIHA
Blood product transfusion complications x5?
- Immune
- Infective
- TRALI
- TACO
- Other = hyperkalaemia, iron overload, clotting
Immunological transfusion reactions?
- Acute haemolytic
- Non-haemolytic febrile
- Allergic/anaphylaxis
Acute haemolytic reaction mushkies?
- ABO incompatible blood e.g. human error
- Fever, abdominal pain, hypotension
- Rx = stop transfusion, confirm Dx, send blood for Coombs, repeat typing and cross matching, supportive care with fluid resuscitation
Non-haemolytic febrile reaction mushkie?
- White blood cell HLA antibodies, often the result of sensitization by previous pregnancies or transfusions
- Fever, chills, red cells (1%), platelets (10-30%)
- Rx = slow or stop transfusion, paracetamol, monitor
Anaphylaxis reaction mushkies?
- Patients with IgA deficiency who have anti-IgA antibodies
- Stop transfusion, IM Adrenaline, ABC
Minor allergic reaction mushkies?
- Foreign plasma proteins
- Pruritis, urticaria
- Temporarily stop the transfusion, antihistamine, monitor
TACO mushkies?
- Excessive rate of transfusion, pre-existing heart failure
- Pulmonary oedema, hypertension
- Rx = Slow or stop the transfusion, consider loop diuretic and oxygen
TRALI mushkies?
- Non-cardiogenic pulmonary oedema thought to be secondary to increased vascular permeability caused by host neutrophils that become activated by substances in donated blood, within 6 hours of transfusion
- Hypoxia, pulmonary infiltrates on chest x-ray, fever, hypotension
- Rx = stop the transfusion, oxygen and supportive care
Differentiating between TACO and TRALI?
TACO = hypertension
Critical mediator of DIC?
TF (Tissue factor) = TF binds with coagulation factors that then triggers the extrinsic pathway (via Factor VII) which subsequently triggers the intrinsic pathway (XII to XI to IX) of coagulation
DIC causes?
- Sepsis
- Trauma
- Obstetric complications (amniotic fluid embolism, haemolysis, HELLP)
- Malignancy
DIC bloods Dx?
- Low platelets and fibrinogen
- Raised PT, APTT and fibrinogen degradation products
- Schistocytes due to MAHA
Warfarin clotting effect?
Prolonged PT
Aspirin clotting effect?
Prolonged bleeding time
Heparin clotting effect?
APTT prolonged (although PT ay be prolonged)
Warfarin antidote?
Vitamin K
Dabigatran antidote?
Idarucizumab
Heparin antidote?
Protamine sulphate
Dabigatran mushkies?
- MOA = direct thrombin inhibitor
- Excretion = majority renal