DVT & PE Flashcards
What are the risk factors for DVT?
- Smoking
- Prolonged Bed Rest
- APLS (Recurrent Miscarriages)
- Obesity
- Immobility
- Pregnancy
- Recent Surgery
- OCPs
- Cancer
- Long Haul Flight
- HRTs
What is the DDx to unilateral leg swelling?
- Deep Vein Thrombosis
- Compartment Syndrome (recent trauma etc)
- Cellulitis
- Necrotising Fasciitis (severely toxic patient)
When can you exclude DVT?
2 of the 3 are -ve: Well’s Score, D-Dimers, USS
What is the acute management of DVT?
Acutely anticoagulate to prevent clot propagation 🡪 AFTER confirming Dx w/ USS
Options:
- LMWH
- DOACs: Apixaban, Rivaroxaban, NOT Dabigatran
- Dabigatran requires a bridging therapy of Parenteral anticoagulation for 5/7
Because unlike CTPA for PE, Doppler USS is much faster, hence we can confirm Dx before starting anticoagulation
Consider:
- Thrombolysis / Thrombectomy if
1) EXTENSIVE / PROXIMAL THROMBOSIS not responding to anticoagulation therapy
2) Phlegmasia cerulea dolens (literally: painful blue inflammation)
What is the chronic management of DVT?
How about for cancer patients?
How about for pregnant ladies?
[Long Term anticoagulation AFTER establishing diagnosis]
Options:
- Warfarin: requires 5 days of bridging w/ either LMWH or DOACs; therapeutic INR of 2-3
- DOACs: Dabigatran, Apixaban, Rivaroxaban
Duration
- For 3-6M for 1st case of DVT
- Indefinitely for recurrent DVT / Hypercoagulable state (such as Ca)
If anticoagulation is C/I 🡪 consider IVC Filter
For all patients: Compressive Stockings and Early Mobilisations
What is the drug choice in extensive DVT or massive PE?
Heparin: these patients were excluded from trials with NOACs
What is the drug choice in patients with high initial risk of bleeding?
Heparin: enable dose titration, rapid offset and availability of protamine as antidote
What is the drug choice in patients with cancer?
- Initial therapy: LMWH, UFH, Rivaroxaban
- Maintenance therapy: LMWH > Rivaroxaban or Edoxaban > Warfarin
What is the drug choice in pregnant patients ?
Pregnancy – both are C/I hence use LMWH
What is the drug choice in patients with liver dysfunction with increased prothrombin time?
Warfarin
What is the drug choice in patients with creatinine clearance <30mL/min?
Warfarin
What is the drug choice in patients with creatinine clearance 30-50mL/min?
Rivoraxaban, apixaban or edoxaban –> less affected by renal impairment than dabigatran
What is the drug choice in patients with dyspepsia or upper GI symptoms?
Rivoraxaban, apixaban or edoxaban
How do you manage thrombosis of superficial vein?
Thrombosis of superficial vein is NOT true DVT 🡪 don’t need to treat
- Can tell difference between superficial and deep via USS
- Mx: repeat USS in 3/12; Give advice to come back if swelling gets worse, symptoms of PE, then rescan them
- Exception: Thrombosis of superficial femoral vein IS CONSIDERED a deep vein
What are the investigations needed if patients are haemodynamically stable?
ECG
- Most sensitive: sinus tachy
- Most specific: S1Q3T3
CXR – Westermark’s sign, Hamptom’s hump
UECr – becuase of DOAC use
ABG – Respiratory alkalosis, desaturation, respiratory failure
BP – obstructive shock
USS Doppler – looking for DVT
TTE – looking for RV dilatation, Tricuspid regurgitation
CTPA – diagnostic
What is the management of haemodynamically stable patient with PE?
1) Acute Resuscitation: Airway, Breathing & Circulation
- Oxygen – 100% via non-rebreather mask
- Set IV access. Send baseline bloods, including clotting. Perform ECG
- Analgesia if required
Calculate Well’s Score
- If HIGH LIKELIHOOD (i.e. score >4) – proceed to (3)
- If LOW LIKELIHOOD (i.e. score ≤4): Risk stratify based on D-Dimers levels (very sensitive, not specific)
- If Elevated – proceed to (3)
- If Not-Elevated – evaluate for other causes of dyspnoea
3) Start Empirical Acute Anticoagulation unless active GI bleed or intracerebral haemorrhage. - LMWH: Bolus dose 5000-10000 units or 80 IU/kg. Maintenance infusion rate until APTT is 1.5-2.5 x control. Check APTT 4-6hr after initial bolus
- DOACs: Apixaban, Rivaroxaban, NOT Dabigatran
4) Send the patient for confirmatory CT Pulmonary Angiogram
5) +ve diagnosis 🡪 SYMPTOMATIC / SUPPORTIVE TREATMENT
- Thrombolysis / Thrombectomy is NOT necessary for stable patient
6) Followed by long term anticoagulation
- Warfarin – requires 5 days of bridging w/ either LMWH or DOACs; therapeutic INR of 2-3
- DOACs – Dabigatran, Apixaban, Rivaroxaban
Duration
- For 3-6M for 1st case of DVT
- Indefinitely for recurrent DVT / Hypercoagulable state (such as Ca)
- If anticoagulation is C/I 🡪 consider IVC Filter
What is the management of acute massive PE?
1) Acute Resuscitation: Airway, Breathing & Circulation
- Oxygen – 100% via non-rebreather mask
- Set IV access. Send baseline bloods, including clotting. Perform ECG
- Analgesia if required
- Manage Cardiogenic Shock – Fluids & inotropes (NE preferred) may be required in sub-massive / massive PE to maintain RV filling
2) Achieve diagnosis via:
- If STABLE after resuscitation 🡪 Send for CTPA for definitive Dx
- If UNSTABLE after resuscitation 🡪 TTE for features of RV dysfunction (RV dilatation, Pulmonary HTN) for presumptive
diagnosis
- NO NEED FOR WELL’S SCORE! Because this is an emergent setting
3) Thrombolysis – 1st line management!
- If no active GI bleed or Cerebral haemorrhage
- Alteplase 100mg/2h peripherally
4) Thrombectomy – indications:
- massive proximal pulmonary embolism with hemodynamic compromise
contraindications to thrombolysis
- No improvement after thrombolysis
5) Followed by long term anticoagulation
