Aidan: Text replacement - "== Clinical Presentation" to "== Clinical Manifestations"

2020-08-02T12:10:40Z

Text replacement - "== Clinical Presentation" to "== Clinical Manifestations"

← Older revision		Revision as of 12:10, 2 August 2020
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	** Elevated Factor VIII		** Elevated Factor VIII

	== Clinical ~~Presentation~~ ==		== Clinical Manifestations ==

	=== History ===		=== History ===

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2020-07-04T01:18:01Z

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== Epidemiology ==

* 1/1000 individuals per year
** 2/3 DVT, 1/3 PE
* 50% of PEs unprovoked

== Risk Factors ==

* Demographic
** Age
** Sex
** Race
** BMI
* Provoking factors
** Surgery/trauma
** Acute medical illness
** Immobility
** Hormonal therapy and pregnancy
** Cancer and chemotherapy
* Hereditary thrombophilias
* Biochemical/Acquired conditions
** Antiphospholipid antibody syndrome
** Elevated Factor VIII

== Clinical Presentation ==

=== History ===

* Assess if it was provoked by a transient risk factor:
** Surgery, hospitalization, or plaster cast immobilization within the last 3 months
** Central venous catheter-associated VTE
** Estrogen therapy, pregnancy, flight over 8 hours, recent leg injury or immobilization within the past 6 weeks

=== Signs & Symptoms ===

* 3+ cm difference in calf circumference measured 10 cm below the tibial tuberosity
* Dilated non-varicose veins
* Tenderness over deep veins
* Homan's sign: flexing the ankle causes calf pain (poor sensitivity and specificity)
* Phlegmasia cerulea dolens

== Well's Criteria for DVT (C3PO + R2D2) ==

* Cancer within 6 months
* Calf diameter increase >3 cm
* Collateral superficial veins (non-varicose)
* Pitting edema confined to symptomatic leg
* Oedema of the entire leg
* tenderness along deep venous system (t = + in mnemonic)
* Recently bedridden for > 3 days
* Recent immobilization of leg (cast, paralysis)
* DVT in the past
* Diagnosis other than DVT likely (2 points off)

== Well's Criteria for PE ==

* Tachycardia (> 100 bpm) 1.5 points
* Hemoptysis 1 point
* Immobilization (< 4wks) 1.5 points
* Signs or symptoms of DVT 3 points
* Active malignancy (<6/12) 1 point
* Previous DVT or PE 1.5 points
* Etiology most likely PE 3 point

== Investigations ==

* Generally don't screen for hereditary thrombophilias, as it does not change management
* No need to screen for occult malignancies (based on [https://www.wikijournalclub.org/wiki/SOME SOME trial 2013]
* CBC, renal and liver function testing, chest X-ray
* Age-appropriate cancer screening

== Management ==

* Anticoagulation
** Acutely, can use unfractionated heparin infusions, if the patient may require interruption of therapy
** Avoid long-term UFH, which is the only anticoagulant shown to have a higher risk of recurrence
* Outpatient treatment options:
** Warfarin 10/5/5 then INRs
** DOACs
*** Apixaban 10mg BID x7d then 5mg BID x3wk then 2.5 BID
*** Rivaroxaban 15mg BID x21days then 20mg OD
*** Dabigatran requires LMWH induction, for some reason
** Low-molecular weight heparins preferred in malignancy ([https://www.wikijournalclub.org/wiki/CLOT CLOT trial])
* Duration of treatment is 3 months if provoked or indefinitely if unprovoked
* For long-term prophylaxis, can consider ASA or rivaroxaban 10mg ([https://www.wikijournalclub.org/wiki/EPCAT_II EPCAT II trial])
* Thrombolysis of unclear benefit, but probably should be used if patient is unstable from PE
* IVC filter
** If there is a contraindication to anticoagulation
** Probably only necessary if acute clot
** Retrievable up to a year

== Prognosis ==

* High risk of recurrence for unprovoked VTE
* After first unprovoked episode, cumulative incidence for recurrence is 16% at 2 years, 25% at 5 years, and 36% at 10 years.
** Men have a 1.4x higher risk
** Positive D-dimer has 2x higher risk
** Proximal DVT 5x higher than distal DVT
** Proximal DVT 1.4x higher than PE alone, and DVT + PE is 1.5x higher than PE alone
* 4% case fatality with recurrent episode
* Provoked is about a third the risk of unprovoked
** The stronger the provoking factor (i.e. major surgery), the lower the recurrence risk

== Further Reading ==

* [https://doi.org/10.1136/bmj.l4363 Longterm risk of symptomatic recurrent venous thromboembolism after discontinuation of anticoagulant treatment for first unprovoked venous thromboembolism event: systematic review and meta-analysis]. ''BMJ''. 2019;366.

[[Category:Thrombosis]]

Venous thromboembolism - Revision history

Aidan: Text replacement - "== Clinical Presentation" to "== Clinical Manifestations"

Maintenance script: Imported from text file