Hypercoagulable Disorder Demo

Category

Features

Classification of venous thromboembolism

  • Deep vein thrombosis (DVT)
    • Typically develops in lower extremity
  • Pulmonary embolism (PE)
    • Usually due to DVT propagating to lung

Terminology

  • Unprovoked DVT
    • No identifiable etiology or inciting event
  • Provoked DVT
    • Due to a known cause or inciting event
  • Proximal DVT
    • Typically in popliteal, femoral, or iliac veins
  • Distal DVT
    • Usually below the knee in calf veins
      • Peroneal
      • Posterior
      • Anterior tibial
      • Muscular veins
  • PE
    • located in the main, segmental, or subsegmental branches of pulmonary arteries

Pathogenesis

  • Altered blood flow (eg, stasis)
  • Altered blood constituents (eg, hypercoagulable state)
  • Vascular endothelial injury

Type

Etiologies

Inherited hypercoagulable states

  • Factor V Leiden mutation
  • Prothrombin gene mutation
  • Protein C deficiency
  • Protein S deficiency
  • Antithrombin deficiency

Acquired risk factors

  • Malignancy
    • Lung
    • Pancreatic
    • Colon
    • Renal cell
    • Prostate
  • Surgery
    • Orthopedic
    • Major vascular
    • Neurosurgery
    • Cancer surgery
  • Drugs
    • Oral contraceptives
    • Hormone replacement therapy
    • Testosterone
    • Tamoxifen
    • Steroids
  • Trauma
  • Pregnancy
  • Prolonged immobilization
  • Antiphospholipid antibody syndrome
  • Renal disease (eg, chronic kidney disease, nephrotic syndrome)
  • Obesity
  • Heparin induced thrombocytopenia
  • Hyperviscosity (eg, hypergammaglobulinemia, polycythemia)
  • Paroxysmal Nocturnal Hemoglobinuria
  • Inflammatory bowel disease

Type

Clinical Features

History

  • Typical findings
    • Unilateral leg swelling
    • Pain in extremity
    • Warmth in extremity
    • Erythema in extremity

Physical examination

  • Possible findings
    • Dilated superficial veins
    • Unilateral leg edema with difference in left and right calf diameter
    • Leg pain with tenderness along pathway of involved vein
    • Regional lymphadenopathy

Clinical Finding

Score

Active cancer (ongoing treatment within 6 months or palliative) 1
Paralysis, paresis, or recent plaster immobilization of lower extremity 1
Bedridden for > 3 days or major surgery with general/regional anesthesia previous 12 weeks 1
Localized tenderness along distribution of deep venous system 1
Entire leg swollen 1
Calf swelling 3 cm larger than asymptomatic side (measured 10 cm below tibial tuberosity) 1
Pitting edema confined to symptomatic leg 1
Collateral superficial veins (non-varicose) 1
Previous documented DVT 1
Alternative diagnosis at least as likely as DVT (eg, Baker cyst in popliteal region, superficial thrombophlebitis, muscle pull/tear, chronic venous insufficiency) -2
Clinical probability score
DVT likely >2 points
DVT unlikely < 2 points

Type

Clinical Features

Low probability of DVT

  • Obtain high or moderate sensitivity D-dimer
    • Normal D-dimer
      • No further testing needed
    • D-dimer > 500 ng/mL
      • Obtain ultrasound of lower extremity
  • Ultrasound of lower extremity
    • Negative
      • No further testing required
    • Positive
      • Start treatment for DVT
    • Nondiagnostic: Consider further testing
      • Repeat ultrasound in 2-3 days
      • CT
      • MRI
      • Venography

Moderate probability of DVT

  • Obtain high or moderate sensitivity D-dimer
    • Normal D-dimer
      • No further testing needed
    • D-dimer > 500 ng/mL
      • Obtain ultrasound of lower extremity
  • Ultrasound of lower extremity
    • Negative
      • No further testing required
    • Positive
      • Start treatment for DVT
    • Nondiagnostic: Consider further testing
      • Repeat ultrasound in 2-3 days
      • CT
      • MRI
      • Venography

High probability of DVT

  • Ultrasound of lower extremity
    • Negative
      • No further testing required
    • Positive
      • Start treatment for DVT
    • Nondiagnostic: Consider further testing
      • Repeat ultrasound in 2-3 days
      • CT
      • MRI
      • Venography

Type

Definitions

Timing

  • Acute PE
    • Symptoms and signs immediately after pulmonary vessel obstruction
  • Subacute PE
    • Symptoms and signs days to weeks after initial event
  • Chronic PE
      • Symptoms of pulmonary hypertension over many years

Hemodynamic stability

  • Massive (high-risk) PE
    • Hemodynamically unstable with systolic BP < 90 mm Hg
  • Submassive (low or intermediate risk PE)
    • Hemodynamically stable PE

Anatomic location

  • Saddle
    • Bifurcation of main pulmonary artery
    • Can extend into right or left main pulmonary artery
  • Lobar, Segmental, Subsegmental
    • Distal movement of embolus to lodge in lobar, segmental, or subsegmental branches of a pulmonary artery

Associated symptoms

  • Symptomatic
    • Can have symptoms leading to radiologic confirmation of PE
  • Asymptomatic
    • Incidentally found on imaging done for another reason

Type

Clinical Features

History

  • Dyspnea at rest or with exertion
  • Pleuritic chest pain
  • Cough
  • Orthopnea
  • Wheezing
  • Calf or thigh pain with swelling
  • Hemoptysis

Physical examination

  • Vital signs
    • Tachypnea
    • Tachycardia
    • Possible fever
  • Extremities examination
    • Calf or thigh swelling with possible:
      • Erythema
      • Edema
      • Tenderness
      • Palpable cords
  • Lung examination
    • Crackles
    • Decreased breath sounds
  • Cardiac examination
    • Accentuated P2 component of second heart sound
    • Elevated jugular venous pressure or distention

Laboratory

  • Arterial blood gas (ABG)
    • Unexplained hypoxemia
    • Widened alveolar-arterial gradient
    • Respiratory alkalosis
    • Hypocapnia
  • Possible elevated D-dimer

EKG/

Chest x-ray

  • EKG
    • Usually sinus tachycardia
    • Possible S1Q3T3
  • Chest x-ray
    • Possibly normal
    • Hampton’s hump
      • Shallow, hump-shaped opacity in periphery of lung
    • Westermark’s sign
      • Sharp cut-off of pulmonary vessels with distal hypoperfusion in a segmental distribution within the lung

Clinical Finding

Score

Clinical signs and symptom of DVT 3
No alternative diagnosis for clinical findings 3
Heart rate > 100 beats/min 1.5
Immobilization > 3 days or surgery in previous 4 weeks 1.5
Previous history of DVT or PE 1
Hemoptysis 1
Malignancy with active treatment in past 6 months or under palliative care 1
Clinical probability score
PE likely >4points
DVT unlikely <4 points

Type

Clinical Features

Hemodynamically unstable patients

  • Stability restored with resuscitation
    • High suspicion for PE
      • Immediate treatment followed by imaging (CT pulmonary angiogram usually preferred)
    • Low suspicion for PE
      • Obtain imaging for confirming diagnosis (eg, CT pulmonary angiogram)
  • Unstable despite resuscitation
    • Obtain bedside ultrasound to evaluate for lower extremity DVT (treat if positive)
    • Can also treat if new right ventricular strain present on EKG

Hemodynamically stable patients

  • Use Wells score for estimating probability of PE
    • Low probability
      • No further testing needed if D-dimer < 500 ng/mL
      • Further testing for elevated D-dimer
    • Intermediate probability
      • No further testing needed if D-dimer < 500 ng/mL
      • Further testing for elevated D-dimer
    • High probability
      • Obtain CT pulmonary angiogram (CTPA) or V/Q scan
        • Treat if imaging positive
      • Use lower extremity ultrasound if unable to do CTPA or V/Q scan
        • Treat if imaging positive
      • Consider pulmonary angiographyif all tests nondiagnostic and high probability

Type Recommendations
Proximal DVT
  • Anticoagulation in all cases unless patient has contraindication
Distal DVT
  • Anticoagulation somewhat controversial for distal DVT
First DVT
  • Initial treatment
    • Low molecular weight heparin for first 5-7 days
  • Subsequenttreatment
    • Either warfarin or direct thrombin inhibitor
  • Duration of treatment
    • Treatment for 3-6 months in most patients
Recurrent DVT
  • Indefinite long-term therapy
  • Consider IVC filter in patients with contraindications for anticoagulation

Type

Clinical Features

Hemodynamically unstable patients

  • Initial treatment
    • Resuscitation with IV fluids and vasopressors if needed
    • Oxygen
    • Immediate anticoagulation
  • Imaging to confirm diagnosis
    • CTPA once hemodynamically stable
    • Bedside echocardiogram if unable to do CTPA
  • Treatment
    • Consider thrombolytics or embolectomy in patients with contraindication to anticoagulation

Hemodynamically stable

  • Initial treatment
    • Oxygen for any hypoxia
    • Consider empiric anticoagulation until confirmation of diagnosis
  • Imaging to confirm diagnosis
    • CTPA preferred
    • Bedside echocardiogram if unable to do CTPA

All patents once stable

  • Initial treatment
    • Low molecular weight heparin for 5-7 days
    • Long-term with either warfarin or direct thrombin inhibitor
  • Duration of therapy for first PE
    • Treatment for 6-12 months in most patients
  • Recurrent PE
    • Indefinite long-term therapy
    • Consider IVC filter in patients with contraindications for anticoagulation

  1. Clinical overview of venous thromboembolism. Schellack, Modau. S Afr Fam Pract 2016;58(1):39-45.
    Link to article
  2. Deep venous thrombosis: a literature review.Osman, Ju, Sun, Qi.Int J Clin Exp Med 2018;11(3):1551-1561.
    Link to article

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