IC4- VTE (DVT/ PE) Flashcards
What are the 3 factors under the Virchow’s Triad?
- Hypercoagulability
- Vascular Damage
- Circulatory stasis
What are some drugs that are risk factors for VTE?
Tamoxifen, raloxifene, ESAs and hormone Tx with estrogen (CoC, HRT)
What is the s/sx for DVT upon clinical presentation?
- Unilateral calf/ leg swelling (edema)
- Circumference of leg/ calf > 3cm difference than other leg/ calf
- Pain (hallmark)
- Warmth (hallmark)
- Tenderness at deep veins
- Colour changes in leg
What are the signs of DVT upon clinical presentation?
- Dilated superficial veins (“palpable cord”)
- Homan’s sign: pain in back of knee upon dorsiflexion of affected leg
What is the process of thromboembolism and how does PE occur?
Embolus above the knee is more likely to embolize → through right heart (inferior vena cava) → pulmonary arteriole system → pulmonary embolism → occlusion of blood flow (vascular supply) to lung → impaired gaseous exchange @ alveoli → necrosis → impaired O2 delivery to other organs → fatal circulatory collapse (if severe)
What are the s/sx for PE?
More respiratory symptoms:
- Cough
- Chest pain
- Chest tightness
- SOB
- Palpitation
- May cough/ spit out blood (hemoptysis)
- If massive: dizziness/ light-headedness
Serious:
Circulatory collapse + shock
What are the signs for PE?
- Tachypnoea
- Tachycardia
- Diaphoretic
- Neck veins may be distended
- Massive PE: cyanotic and hypotensive; Oximetry: hypoxic
(May go into cardinal shock and die within minutes)
What should we do after a DVT is suspected?
Complete the Well’s DVT score
What are the Well’s score factors and the scores for each? (8)
ALL 1 point each:
- Active cancer (treatment ongoing/ within previous 6 months/ palliative)
- Paralysis, paresis, recent plaster immobilization of lower extremeties
- Recently bedridden for ≥ 3d or major surgery within 4w
- Localized tenderness along distribution of deep venous system
- Entire leg swollen
- Calf swelling > 3cm when compared to asymptomatic leg (measured below tibial tuberosity)
- Pitting edema (greater in symptomatic leg)
- Collateral superficial veins (nonvaricose)
After the Well’s Score is done, if the patient has ≥ 3 points (DVT likely), what is the next step? Elaborate
Conduct Doppler ultrasound (complete duplex ultrasound).
- If proximal ultrasound negative → surveillance
- If distal DVT → anticoagulation or surveillance
- If proximal DVT → initiate anticoagulation
After the Well’s Score is done, if the patient has 0 points (DVT unlikely), or 1-2 points (moderate/ intermediate likelihood of DVT), then what is the next step? Elaborate
D-dimer test.
If D-dimer positive, proceed with Dopper Ultrasound imaging, next course of action depends on imaging results.
If D-dimer negative, then rule out DVT.
What are the factors of high-severity PE? (4)
- Haemodynamic instability
ONE of the following:
- Cardiac arrest
- Obstructive shock (SBP < 90 mmHg/ vasopressors required to achieve BP ≥ 90 mmHg despite adequate filling status in combination with end-organ dysfunction)
- Persistent hypotension (SBP < 90 mmHg or SBP drop ≥ 40 mmHg for > 15 min not caused by new-onset arrhythmia, hypovolemia or sepsis)
- PESI class III-V or sPESI ≥ 1
- RV dysfunction on TTE or CTPA
- Elevated cardiac troponin levels
What are the factors for intermediate-high severity PE? (3)
- PESI class III-V or sPESI ≥ 1
- RV dysfunction on TTE or CTPA
- Elevated cardiac troponin levels
When do we use thrombolytics?
ONLY use in very severe PE where patient is at high risk of death/ with haemolytic deterioration on anticoagulant Tx
What are the Well’s score factors for PE and the respective scores for each factor? (7)
- Clinical SSx of DVT (leg swelling, pain with palpitation) → 3 points
- Other diagnosis less likely than PE → 3 points
- HR > 100 → 1.5 points
- Immobilization (≥ 3 days) or surgery in previous 4w → 1.5 points
- DVT/ PE Hx → 1.5 points
- Hemoptysis → 1 point
- Malignancy → 1 point
What is the Well’s score for likely PE and unlikely PE?
> 4 points = PE likely
≤ 4 points = PE unlikely