Haematology Flashcards
What to rx if DVT likely
straight to DOAC
lmwh no longer recommended as it means patient doesnt need to switch to alt treatment for 3/6 months (provoked/unprovoked)
Wells score of 2 or more means what
DVT likely
Do leg USS ideally within 4 hours
If not possible, do d-dimer and commence DOAC whilst waiting
If USS neg but DVT likely, await d-dimer
If scan neg but d dimer pos, stop DOAC and offer repeat scan in 1 week
If WELLs score 1, what does this mean?
Unlikely DVT
Do d-dimer, if d-dimer negative = good
if d-dimer positive, do USS
If waiting longer than 4 hours for anything and DVT a suspicion, commence DOAC as can always stop
What to rx if DOAC not suitable for a patient in the mx of DVT
LMWH followed by dabigatran or edoxaban OR LMWH followed by a vitamin K antagonist (VKA, i.e. warfarin)
think severe renal impairment (eGFR <15), metallic heart valve, or ventricular thrombus, APS, pregnant
Provoked VTE - duration of anticoagulation
3 months
Unprovoked VTE - duration of anticoagulation
6 months
Sequestration crises in sickle cell - what is it?
sickling within organs such as the spleen or lungs causes pooling of blood with worsening of the anaemia
associated with an increased reticulocyte count
Sickle cell aplastic crisis - what is it?
caused by infection with parvovirus
sudden fall in haemoglobin
bone marrow suppression causes a reduced reticulocyte count
what is an acute chest syndrome in sickle cell disease
vaso-occlusion within the pulmonary microvasculature → infarction in the lung parenchyma
dyspnoea, chest pain, pulmonary infiltrates on chest x-ray, low pO2
management
pain relief
respiratory support e.g. oxygen therapy
antibiotics: infection may precipitate acute chest syndrome and the clinical findings (respiratory symptoms with pulmonary infiltrates) can be difficult to distinguish from pneumonia
transfusion: improves oxygenation
What is a thrombotic crisis in sickle cell disease
also known as painful crises or vaso-occlusive crises
precipitated by infection, dehydration, deoxygenation (e.g. high altitude)
painful vaso-occlusive crises should be diagnosed clinically - there isn’t one test that can confirm them although tests may be done to exclude other complications
infarcts occur in various organs including the bones (e.g. avascular necrosis of hip, hand-foot syndrome in children, lungs, spleen and brain
Called to see a patient, trasnfusion recently started. Febrile and anxious, otherwise obs fine
Non-haemolytic febrile reaction
Give paracetamol, slow or stop transfusion
Monitor
Transfusion commenced, patient develops uritcaria and pruritis
Minor allergic reaction
Stop transfusion, antihistamine, monitor
Hypotension, angioedema, wheeze, SoB post commencement of transfusion
Anaphylaxis
Stop transfusion, adrenaline IM, ABC support (fluids, 02)
Fever, abdominal pain, hypotension post commencement of transfusion
Acute haemolytic reaction
ABO incompatibility
Stop transfusion
Check blood products
Fluid resus
Pulmonary oedema, HTN, background HF in Hx, recent start of transfusion
Transfusion-associated circulatory overload (TACO)
Slow, stop, Consider intravenous loop diuretic (e.g. furosemide) and oxygen
Hypoxia, pulmonary infiltrates on chest x-ray, fever, hypotension post commencement of transfusion
Transfusion-related acute lung injury (TRALI)
Non-cardiogenic pulmonary oedema thought to be secondary to increased vascular permeability caused by host neutrophils that become activated by substances in donated blood
Stop the transfusion
Oxygen and supportive care
What is polycythaemia rubra vera
a myeloproliferative disorder caused by clonal proliferation of a marrow stem cell leading to an increase in red cell volume, often accompanied by overproduction of neutrophils and platelets
Mutation in what gene results in Pcrv
JAK 2 mutation
Features of PCRV
pruritus, typically after a hot bath
splenomegaly
hypertension
hyperviscosity
arterial thrombosis
venous thrombosis
haemorrhage (secondary to abnormal platelet function)
low ESR
What is hodgkins lymphoma
a malignant proliferation of lymphocytes characterised by the presence of the Reed-Sternberg cell. It has a bimodal age distributions being most common in the third and seventh decades
What are the B cell symptoms
fever
night sweats
weight loss
What is the relevance of B cell symptoms
poor prognosis
large spleen, abdo pain, sickle cell disease, anaemia
sequestrant crisis
why is warfarin contraindicated in pregnancy?
teratogenic
thats why LMWH is used in DVT tx
