Platelet Problems & Thrombosis Flashcards
Mucosal bleeding is a sign of ______
Primary haemostasis failure
Give 4 examples of mucosal bleeding
Epistaxis
Menorrhagia
GI
Conjunctiva
Purpura is a sign of _____
Primary haemostasis failure
What are the signs of primary haemostasis failure?
Easy bruising
Purpura
Mucosal bleeding
ICH
Primary haemostasis failure could be due to a promblem with which components?
Vascular problem
Thrombocytopenia
Platelet function
VWF problem
Name 3 vascular causes of primary haemostasis failure?
HSP
Vit C deficient
Marfan (interferes with endothelial collagen)
Vitamin C deficiency is seen is what group of people?
Alcoholic - easy bruising
HSP
- Affects what age group?
- Occurs following a recent what?
- Has what effect on PLT count?
- Can cause bleeding where?
- Children
- Recent infection
- Normal PLT count
- PR bleeding
Thrombocytopenia can be classified by cause as ….
Decreased production
Increased destruction
What causes decreased PLT production?
Bone marrow problem eg leukaemia, myeloma, met
What causes increased platelet destruction?
Hypersplenism (portal HTN)
ITP
HUS
DIC
What does ITP stand for?
Immune thrombocytopaenic purpura
What drug interfere with platelet function?
Antiplatelets and NSAIDs
How does chronic kidney disease cause primary haemostasis failure?
Raised urea interferes with platelet function
Von Willebrand Disease
- Method of inheritance?
- Gender effected?
AD
M=F
Von Willebrand Disease
-Common or rare?
-Common
Von Willebrand Disease
-Typical presentation?
Menorrhagia, epistaxis, easy bruising
Von Willebrand Disease
-Effect on PT and APTT?
Normal PT, raised APTT
Von Willebrand Disease
-Management?
IJ desmopressin DDAVP
ITP
- What age range does it occur in?
- Has what effect on PLT count?
Children or adults
Decreased PLTs
What is the management of ITP?
PO CCS
Secondary haemostasis failure:
A single factor deficiency is likely to due to a ______ cause.
Multiple factor deficiencies is likely due to an ______ cause.
Single hereditary
Multiple acquired
Name 3 causes of multiple clotting factor deficiencies
Cirrhosis
DIC
Vitamin K deficiency
Why can cirrhosis cause clotting factor deficiencies?
Clotting factors synthesised in liver hepatocyte
What effect does cirrhosis have on D-dimers, PLT count, PT and APTT?
Normal D-dimers
Low platelets
Raised PT
Raised APTT
Name causes of vitamin K deficiency
Diet Absorption Warfarin antagonist Obstructive jaundice eg gallstone Haemorrhagic disease of the newborn
What is given as prophylaxis against haemorrhagic disease of the newborn?
Vit K IJ
What is required for vitamin K absorption?
Bile salts
Also fat soluble
Vitamin K deficiency effects factors ……
II, VII, IX, X
Also protein C and S
What are the 2 types of haemophilia? Which is more common? Which factors are effect in each type?
A - VIII (80%)
B - IX
What is the inheritance pattern in haemophilia?
X linked
How does haemophilia present?
Recurrent haemarthrosis Easy bruising Haematuria Haematomas Prolonged bleeding after minor procedure
What is haemarthrosis? Which areas of the body are most effected? What is the pathological response?
Bleeding into a joint space
Ankle, elbow, knee
Neovascularisation
What is the complication of haemarthrosis in haemophilia?
Haemophilic arthropathy
Mx joint replacement
What effect does haemophilia have on platelet count, APTT and PT?
Normal PLT count
Raised APTT
Normal PT
What is the management of haemophilia?
IV infusion of factors every 2 days
What is DIC?
Disseminated intravascular coagulation
Increased and inappropriate haemostasis activation
What stages of haemostasis are effected in DIC?
Primary + secondary + fibrinolysis
What leads to organ failure in DIC?
Microvascular thrombus formation
What is the aetiology of DIC?
DIC is not a diagnosis
Massive trauma eg RTA Septic/hypovolaemic shock ABO incompatible Obstetric emergency Cancer
What effect does DIC have on D-dimers, PLT count, PT and APTT?
Very raised D-dimers
Decreases platelets
Raised PT
Raised APTT
What is the management of DIC?
Tx cause
Replace fibrinogen
Transfuse PLT + plasma
Where are common sites of arterial and venous thrombosis?
Arterial: coronary, cerebral, peripheral
Venous: DVT, PE
Arterial thrombus is _____ rich and happens in a _____ pressure system. The drug class of choice is ______.
Venous thrombus is _____ rich and happens in a _____ pressure system. The drug class of choice is ______.
Arterial thrombus is PLATELET rich and happens in a HIGH pressure system. The drug class of choice is ANTI-PLATELETS.
Venous thrombus is FIBRIN rich and happens in a LOW pressure system. The drug class of choice is ANTI-COAGULANTS.
What are some risk factors for arterial thrombosis?
BP HTN Smoke Atherosclerosis DM
What are the components of Virchow’s triad?
Hypercoagulability
Stasis
Valve damage
Venous thrombosis activates the _____
Coagulation cascade
Pulmonary embolisms cause ____ sided heart strain and knife like sharp pain on ____.
Right
Inhalation
Do DVTs cause pitting or non-pitting edema?
Pitting
What are some non-modifiable risk factors for VTE?
Age
Family history
PMH VTE
Thrombophilia
What is the strongest RF for VTE?
PMH VTE (damages endothelium)
What are some modifiable RF for VTE?
Obesity Cancer Immobility Puerperium/pregnant Estrogen eg CHC Trauma Infections
Multiple risk factors for VTE have _____ effect
Synergistic
Why is infection a risk factor for VTE?
Some clotting factors are acute phase proteins
Thrombophilia increases the risk of ____
VENOUS thrombosis
What is a cause of acquired thrombophilia?
APS
What are some genetic causes of thrombophilia?
Factor V Leiden deficient
Antithrombin deficient
Prothrombin mutation
Protein C/S deficient
What is the pathology of factor V Leiden deficiency?
Protein C and S less effectively switches off factor V
What are some red flags for factor V Leiden deficiency?
VTE under 45yr
Recurrent VTE
VTE in unusual place eg arm
What drug should be avoided in factor V Leiden deficiency?
CHC
What is the management of factor V Leiden deficiency in pregnancy?
Heparin
What is the management of factor V Leiden deficiency ONLY if VTE recurs?
PO long-term anticoagulant
APS causes ____ and ____ thrombosis
Arterial and venous
What stages of haemostasis are effected in APS?
Primary + secondary
What effect does APS have on PLT count, PT, APPT?
Mild decreased PLTs
Normal PT
Raised APTT (not deficient but interferes w test)
What autoantibodies are found in APS?
B2 glycoprotein Ab
Lupus anticoagulant
What are the 2 most common complications of APS?
Miscarriage
Stroke
What is the management of APS?
Aspirin, warfarin
