Haemostasis & Thrombosis Flashcards
What do platelet cell membranes contain?
Phospholipids
Glycoproteins
What is the role of glycoproteins?
Receptors for agonists, adhesive proteins, coagulation factors and other platelets
What are the function of phospholipids?
Prostaglandin synthesis, calcium mobilisation, coagulant activity localisation to surface of platelet
What do platelet specific granules contain?
ADP, dense osmophillic granules
What do alpha granules contain?
Series of different proteins - VWF, platelet factor 4, factor V, fibrinogen, fibronectin, platelet derived GF, tissue plasminogen activator inhibitor-1
What are some serious inherited platelet disorders?
Bernard Soulier syndrome
Glanzmann’s
What is Bernard Soulier syndrome?
When you lack Gp1b
What is Glanzmann’s syndrome?
When you lack GpIIB or GpIIIa
What are some less serious inherited platelet disorders?
Storage pool disorders
Weak agonist response defects
What are the different types of VWD and how do they differ?
Type 1 - mild to moderate deficiency
Type 2 - protein is present but is defective
Type 3 - total absent protein
How can VWD be treated?
DDAVP if mild (desmopressin)
Tranexamic acid (antifibrinolytic)
VWF containing concentrate
Where is tissue factor found?
present on subendothelial tissue and is expressed by cells which are normally not exposed to flowing blood, injury exposes TF to flowing blood
How can haemophilia be severe?
Bleed spontaneously and be potentially fatal if you have an intracranial bleed for example
Where do normal bleeds occur in haemophilia?
Soft tissue, joints (knees/ankles/elbows), psoas, intracranial, operative sites, can form haematomas
What should treatment be for mild & moderate haemophilia?
DDAVP (desmopressin) if haemophilia A
factor concentrate - can’t self administer
