thrombotic disorders Flashcards
what is a thrombus
a clot that arises ‘in the wrong place’
what is a thromboembolism
then the thrombus moves along the vessel
what is virchows triad
stasis
vessel damage
hypercoagubility
what is an arterial thrombosis made up of
platelet and fibrin clot
risk factors for arterial thrombosis
age smoking diabetes sedentary lifestyle hypertension obesity
what can an arterial thrombosis cause
ischaemia and infarction
symptoms depend on site (stroke, MI, acute limb ischaemia etc)
what is a venous thrombus made of
fibrin and RBCs
why do venous clots form
usually because of stasis and hypercoagulability
what can venous thrombi cause
DVT
PE
thrombophlebitis
risk factors for venous clots
age pregnancy hormone therapy trauma immobility surgery obesity FH systemic disease
what systemic diseases can increase risk of VTE
cancer
IBD
connective tissue diseases
what could you use for probability testing in VTE
wells
geneva score
investigations for thromboembolisms
d-dimer
doppler
V/Q scan
angiogram
what is factor V leiden
hereditable disease
mutation of factor V
means protein C can’t bind to it
what is the result of factor V leiden
excess clotting in veins
when chould you suspect factor V leiden
young (<45) Caucasian patient with a clot
what is microvascular thrombus
platelets/fibrin in small vessels
what does microvascular thrombus cause
diffuse ischaemia
when is microvascular thrombosis seen
disseminated intravascular coagulopathy
what is disseminated intravascular coagulopathy
serious condition where blood clots form in blood vessels all over the body
what are some examples of precipitating factors that can cause DIC
shock sepsis major trauma/burns malignancies obstetric emergencies severe immune related conditions severe organ dysfunction
what is the pathology of DIC
systemic inflammatory response to the trigger
upregulation of TF and other pro-coagulants
activation of clotting cascade
what happens to circulating clotting factor concentration in DIC
decreases because all the clotting factors are being used up
do you get thrombocytopenia in DIC
yes
platelets are being used up
presentation of DIC
bleeding from unusual sites like nose, GI tract, ears widespread easy bruising confusion/disorientation petechia or purpura widespread skin necrosis oliguria hypotension
investigations for DIC
FBC - thrombocytopenia
coagulation screen
D-dimer - elevated
management of DIC
treat underlying cause
platelet transfusions for bleeding
concentrated solutions of clotting factors
heparin if there is lots of thrombosis
lower dose oral heparin if patient is non-bleeding
complications of DIC
organ failure haemorrhage cardiac tamponade haemothorax gangrene intracranial haemorrhage
