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Long Case - Haematology > Bleeding disorders > Flashcards

Flashcards in Bleeding disorders Deck (5)
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1

Three processes that stop bleeding?

1. vasoconstriction
2. platelet aggregation
3. coagulation cascade

2

Vascular and platelet causes

VASCULAR DEFECTS
Inherited
- Connective tissue diseases
Acquired
- Infection = meningococcal, measles
- Henoch-schoenlein purpura (IgA vasculitis)

PLATELET DISORDER
Decreased production
- Viral infection
- Drugs + Radiotherapy
- Bone Marrow failure = aplastic and megaloblastic anaemia, marrow infiltration eg. leukaemia or myeloma

Increased Destruction
- Autoimmune = ITP, SLE
- Non-immune = DIC, Thrombotic thrombocytpoenic purprura (TTP), Sequestration in hypersplenism

Poorly functioning Platelets
- Myeloproliferative disease
- NSAIDs
- elevated urea

3

Coagulation disorders

INHERITED
Haemophilia
- X linked, mainly affecting men
- type A = F8 deficiency, Type B = F9 deficiency
- treat by replacing missing factor

Von Willebrand's Disease
- VWF brings platelets together and causes binding with each other and with endothelial wall damage
- give VWF rich factor 8 for surgery etc

ACQUIRED
Anticoagulants
- Warfarin, Rivaroxaban, Dabigatran

Vitamin K deficiency

Liver Disease
- decreased production of all factors except 8

DIC
- widespread activation of coagulation causing thrombus, followed by bleeding/bruising as clotting factors are used up

Massive blood loss
- Loss of factors and dilution of remaining factors with fluids

4

Investigations necessary

1. Platelet count
2. Megakaryocytes in marrow
- low = decreased production
- high = increased destruction
3. Anti-platelet AB
4. APTT
- factors 8,9,11,12 are only assessed using APTT
- correctable = factor deficiency, not = inhibitor eg. SLE
5. PR
- 2,5,7,10, fibrinogen, prothrombin = extrinsic and common
- If PR high and APTT normal then must be factor 7
6.Thrombin Clotting Time (TCT)
- Fibrinogen deficiency
- Thrombin inhibitor (eg. heparin and dabigatran)
7. Factor Assays

5

Magegement:

Control any bleeding and eliminate the inhibitor
- reverse and stop Anti-coags
- give steroids and immunosuppresives in acute
avoid giving blood/plasma but give FFP if needed
- educate pts on increased bleeding risk