CVS clinical cases Flashcards
if someone has swelling in lower limb which is painful and is common with people on long flights
DVT
what can DVT lead to if the symptoms are sudden breathlessness and pain to breath
pulmonary embolus
why specifically can a lower limb start to swell
DVT causes disruption to normal circulation and forms block of vessel leads to stasis of blood which leads to plasma leaking out the vessel and causing oedema
what does a DVT look like
swelling, pain, tender, inflammation, warmth
which veins are most at risk to DVT
femoral, popliteal, tibial vein, lesser saphenous, greater saphenous, iliac
how does immobility lead to DVT
lower limb muscles aid in return on blood to the heart
without it you only have the valves and little pressure from the heart
what is a thrombus
blood clot
what is virchows triad
theory concerning homeostasis thrombosis was the result of a delicate interplay between three factors which promote coagulation these are 1 changes in blood flow 2 changes in the vessel wall 3 changes in blood constituents
what is stasis
stagnation or cessation of blood flow
in stasis why is blood prone to clotting
platelets are in contact with the endothelium - clotting factors are not diluted by fast blood flow
inflow of anticoagulants uis slowed
what changes in the vessel wall can lead to DVT
damage to the lining of the vein due to inflammation (vasculitis)
chemotherapy
what causes changes in blood flow to result in DVT
thrombophilia - abnormal factor V leiden which makes clotting more likely cancer smoking contraceptive pill pregnancy
what is an embolus
material such as blood clot, fat, air, amniotic fluid or foreign body carried by the blood and lodged in a mother area
what is a venous thromboembolism
DVT
why is oxygen saturation lowered in pulmonary embolism
V/Q mismatch
there is ventilation but no perfusion of blood due to clot
how does D -Dimer test for DVT/VTE
what are the problems with the test
when you have a DVT you get large amount of D-dimer which is a product of fibrin breakdown
sesntivte test but not specific to DVT - can be caused by other diseases such as eclampsia, kidney disease, infection, liver disease
what techniques can be used to test for VTE
doppler ultrasund
V/Q scan
computed tomography pulmonary angiogram (CTPA)
what treatments are there for DVT or pulmonary embolism
warfarin (pills) - monitored low molecular weight heparin (anticoagulant) - acute action (sub cutaneous) Xa inhibitors - rivaroxaban - apixaban - edoxaban
what is warfarin
Warfarin inhibits the effective synthesis of biologically active forms of the vitamin K-dependent clotting factors: II, VII, IX and X, as well as the regulatory factors protein C, protein S and protein Z.
anticoagulant - used in cases of thrombophilia
how would you reverse warfarin
give Vit K
in extreme cases give large amounts of prothrombin
what advice would you give someone to reduce DVT and pulmonary embolism
stop smoking lose weight regular walking keep hydrated compression stocking
what is a cerebral infarction
stroke
what is a stroke and what can it be caused by
rapidly developing loss of brain function due to disturbance in the blood supply to the brain
it can occur via blockage by thrombus (ischaemic stroke)
or by haemorrhage (haemorrhage stroke)
what is a cerebral haemorrhage
rupture of a blood vessel can produce bleeding
when an aneurysm ruptures - 15-20% of all strokes and are deadly
best preventative by controlling high blood pressure