DVT and PTE Flashcards
What does DVT stand for?
Deep vein thrombosis
What does PE stand for?
Pulmonary embolism
What are the parts of virchows triad?
Stasis
Hypercoagulability
Vessel damage
Examples of cause of stasis
Bed rest
Travel
Examples of causes of hypercoagulability
Pregnancy
Trauma
Example of vessel damage
Atherosclerosis
Examples of VTE
Limb DVT PE Visceral VT Intracranial VT Superficial thrombophlebitis
Features of a venous thrombus
Red thrombus
Fibrin and red cells
What does a venous thrombus result in?
Back pressure
What are venous thrombus principally due to?
Stasis
Hypercoagulability
Features of arterial thrombus
White clot
Platelets and fibrin
What does arterial thrombus result in?
Ischaemia
Infarction
What are arterial thrombus principally secondary to?
Atherosclerosis
Presentation of DVT
Unilateral limb swelling Persisting discomfort Calf tenderness Warmth Erythema May be clinically silent
Presentation of PE
Pleuritic chest pain
Dyspnoea
Haemoptysis
Tachycardia
What would you hear on auscultation of a PE?
Pleural rub
Features of pleuritic chest pain
Sharp
On inspiration
Presentation of massive PE
Severe SOB Collapse Cyanosis (blue lips and tongue) Tachycardia Low BP Raised JVP Altered heart sounds May cause sudden death
Potential long term consequence of PE
Most recover fully
Pulmonary HTN
Risk factors for VTE
Increasing age Tissue trauma Immobility Obesity Pregnancy Exogenous oestrogen Smoking Cancer Inheritance Long haul travel (ALL CAUSING STASIS/HYPERCOAGULABILITY)
Examples of exogenous oestrogen
OCP
HRT
What is heritable thrombophilia?
An inherited predisposition to venous thrombosis
Most common type of heritable thrombophilia
Factor V Leiden
Long haul travel risk with VTE is increased in who?
Short Tall Overweight Women on OCP Window seats
Investigations for DVT
Clinical
D dimer
Compression USS
What score is done for clinical probability assessment for DVT and PE?
Wells score
What does the wells score look at?
Active cancer Paralysis / plaster Bed > 3 days / surgery within 4 weeks Tender veins Entire leg swelling Calf swelling > 3 cm Pitting oedema Collateral veins Alternative diagnosis likely (-2) (All rest 1 each)
Score of wells score
Low (0 or less) - approx. 3 % risk
Moderate (1 or 2) - approx. 17% risk
High (3 or more) - approx. 75% risk
Investigations for PE
Clinical assessment D dimer Isotope ventilation Perfusion scan (V/Q) CT pulmonary angiogram (CTPA)
Prevention of VTE in hospital
Early mobilisation
Anti embolism stockings
Daily injections of LWMH
Indications of graduated compression stockings
Prevention of DVT Chronic venous insufficiency Varicose veins Oedema Lymphoedema Prevention of post phlebitic syndrome
Treatment of VTE
DOAC (apixaban or rivaroxaban) 1st for 5 or more days
Then oral anticoagulant (warfarin) for 3 months
Thrombolysis for massive PE
(Vena caval filter)
Massive PE + what = thrombolyse?
Hypotension
Patients taking warfarin should avoid what?
Foods high in vitamin K
- sprouts
- broccoli
- kale
- spinach
ECG changes with PE
Sinus tachycardia
S1Q3T3 (only 10%)
Describe S1Q3T3
Deep S waves in I
Pathological Q waves in III
Inverted T waves in III
What does S1Q3T3 indicate?
Right heart strain
What is a CTPA contraindicated in?
Renal impairment
Allergy to the contrast media
What would the ABG show in a PE?
Respiratory alkalosis
