DVT Flashcards
How does swelling occur in DVT?
increased hydrostatic pressure within veins by obstruction
consequent back pressure raises capillary hydrostatic pressure
causes fluid to move out into tissues
What does fluid movement depend on?
balance between net oncotic and net hydrostatic pressures
What are the signs of DVT?
calf warmth tenderness swelling erythema mild fever pitting oedema vein distension unilateral localised pain Homan's sign
What is Homan’s sign?
discomfort behind the knee on forced dorsiflexion of the foor
What are the risk factors of DVT?
age trauma surgery Hx of DVT/PE obesity heart failure
What are the investigations for DVT?
USS doppler
? underlying malignancy
thrombophilia screen
What scoring system is used for suspected DVT?
Wells score (2+ points)
How soon should a doppler of the proximal leg vein be performed?
within 4 hours
What is a doppler is not possible?
within 4 hours:
D-dimer
interim therapeutic anti-coagulation
proximal leg vein ultrasound
What are first line anti-coagulation for DVT?
apixaban/rivaroxiban
What is second line for DVT?
LMWH for 5 days followed by dabigatran/edoxaban
or LMWH with vitamin K antagonist
What tests need to be carried out alongside anticoagulation?
FBP
U&E
LFTs
What is the duration of treatment for DVT?
3 months
How long should treatment for DVT be for cancer patients?
6 months
If no cause is identified for DVT how long should treatment be?
6 months
What is the target for INR?
2-3
What are surgical options for DVT when anticoagulants fail or active bleeding occurs/contraindications?
inferior vena cava filters
percutaneous thrombectomy
If the DVT is unprovoked, what is the patient screened for?
cancer
thrombophilia
What are teh complications of DVT?
PE
cardiac arrest
post-thrombotic syndrome
What are the investigations for suspected DVT?
antiphospholipid Abs
What are the 3 areas of Virchows triad?
stasis of blood flow
hypercoagubility
endothelial injruy
What is the prevention for DVT?
stop combined OCP 4 weeks pre-op mobilise early during admission LMWH for high risk patients after VTE assessment compression stockings intermittent pneumatic compression
What are post-thrombotic syndrome symptoms?
chronic leg swelling stiffness pain tingling cramps leg ulcers