Pulmonary embolism: Difference between revisions
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====Moderate Probability====
====Moderate Probability====
*Controversial
*D-dimer
**Unclear whether d-dimer alone is sufficient to rule-out PE<ref>ACEP Clinical Policy. http://www.acep.org/Content.aspx?id=80787 </ref>
**However, it is unclear whether d-dimer alone is sufficient to rule-out PE<ref>ACEP Clinical Policy. http://www.acep.org/Content.aspx?id=80787 </ref>


====High Probability====
====High Probability====

Revision as of 08:20, 22 December 2014

See Pulmonary Embolism in Pregnancy for pregnancy specific information.[1]

Background

Clinical Spectrum of Venous Thromboembolism

Clinical Spectrum of Venous thromboembolism (VTE)

Only 40% of ambulatory ED patients with PE have concomitant DVT[2][3]

Types

Clinical Presentation

Symptoms

Signs

  • Tachycardia (HR>100), Tachypnea (RR>20), Hypoxemia (SpO2<95%) are seen ~50% of the time
  • Hypotension (SBP<90) only seen 10% of the time, but largest predictor of mortality
  • Unilateral calf tenderness or edema, suggestive of a DVT
  • Other signs may include accentuated pulmonic component of second heart sound, JVD, or decreased breath sounds

Diagnosis

Wells Criteria

  1. Symptoms of DVT - 3pts
  2. No alternative diagnosis better explains the illness - 3pts
  3. HR > 100 - 1.5 pts
  4. Immobilization within prior 4wks - 1.5pts
  5. Prior history of DVT or PE - 1.5pts
  6. Active malignancy - 1pt
  7. Hemoptysis - 1pt

Wells Score

  1. 0-1 point: Low probability (3.4%)
  2. 2-6 points: Moderate probability (27.8%)
  3. 7-12 points: High probability (78.4%)

Workup by Probability

Low Probability

  • If low prob and PERC Rule negative, then no workup
  • If low prob and PERC Rule positive, then d-dimer

Moderate Probability

  • D-dimer
    • However, it is unclear whether d-dimer alone is sufficient to rule-out PE[4]

High Probability

  • Consider anticoagulation before imaging!
  • CTPA if GFR >60
  • V/Q if GFR <60

Differential Diagnosis

Chest pain

Critical

Emergent

Nonemergent

Treatment

Supportive care

  • Give IVF to increase preload

Anticoagulation

  • Indicated for all patients with confirmed PE or high clinical suspicion (don't wait for imaging)
  • Treatment options:
    • LMWH SC
      • 1st line for most hemodynamically stable pts
      • contraindicated in renal failure
      • Enoxaparin 1 mg/kg SC q12h
      • Dalteparin 200 IU/kg SC q24h, max 18,000 IU
    • Unfractionated Heparin
      • Consider in pts w/:
        • Persistent hypotension
        • Increased risk of bleeding
        • Recent sx/trauma
        • Renal failure (GFR <30)
        • Morbid obesity or anasarca (poor sc absorption)
        • Thrombolysis is being considered
      • 80 units/kg bolus; then 18 units/kg/hr
        • Check PTT after 6hr; adjust infusion to maintain PTT at 1.5-2.5x control

Thrombolysis

  • Major controversy exists regarding thrombolytic therapy in submassive PE. Therapy should be individualized to patients.[5][6][7] 'The mortality benefit may be greatest in patients with right ventricular dysfunction. [8]
  • Bleeding risk is increased with increasing age especially in the group ≥ 65 yo[9]

Indications

  1. Patients with massive PE and acceptable risk of bleeding complications
  2. Pt w/ submassive PE w/ evidence adverse prognosis + low risk of bleeding complications
    1. Hemodynamic instability
    2. Worsening respiratory insufficiency
    3. Severe Right Ventricular dysfunction
    4. Major myocardial necrosis

Thrombolytic Instructions

  1. Review contraindications
  2. Discontinue heparin during infusion
  3. tPA 100mg over 2hr OR 0.6 mg/kg over 2min
  4. After infusion complete measure PTT
    1. Once value is <2x upper limit restart anticoagulation

Absolute contraindications

  1. Any prior intracranial hemorrhage,
  2. Known structural intracranial cerebrovascular disease (e.g. AVM)
  3. Known malignant intracranial neoplasm
  4. Ischemic stroke within 3mo
  5. Suspected aortic dissection
  6. Active bleeding or bleeding diathesis
  7. Recent surgery encroaching on the spinal canal or brain
  8. Recent closed-head or facial trauma w/ radiographic evidence of bony fx or brain injury

Relative contraindications

  1. Age >75 years
  2. Current use of anticoagulation
  3. PE in Pregnancy
  4. Noncompressible vascular punctures
  5. Traumatic or prolonged CPR (>10min)
  6. Recent internal bleeding (within 2 to 4 weeks)
  7. History of chronic, severe, and poorly controlled hypertension
  8. Severe uncontrolled HTN on presentation (sys BP >180 or dia BP >110)
  9. Dementia
  10. Remote (>3 months) ischemic stroke
  11. Major surgery within 3 weeks

IVC Filter

  • Indications
    • anticoagulation contraindicated in pt with PE
    • failure to attain adequate anticoagulation during treatment

See Also

Thrombolytics for pulmonary embolism

External Links

References

  1. ↑ D-Dimer Concentrations in Normal Pregnancy: New Diagnostic Thresholds Are Needed. Kline et all. Clinical Chemistry May 2005 vol. 51 no. 5 825-829 http://www.clinchem.org/content/51/5/825.long
  2. ↑ Righini M, Le GG, Aujesky D, et al. Diagnosis of pulmonary embolism by multidetector CT alone or combined with venous ultrasonography of the leg: a randomised non-inferiority trial. Lancet. 2008; 371(9621):1343-1352.
  3. ↑ Daniel KR, Jackson RE, Kline JA. Utility of the lower extremity venous ultrasound in the diagnosis and exclusion of pulmonary embolism in outpatients. Ann Emerg Med. 2000; 35(6):547-554.
  4. ↑ ACEP Clinical Policy. http://www.acep.org/Content.aspx?id=80787
  5. ↑ Elliott C. et al. Fibrinolysis of Pulmonary Emboli — Steer Closer to Scylla.
  6. ↑ Sharifi M et al. Moderate pulmonary embolism treated with thrombolysis (from the “MOPPETT trial). J Cardiol 2013; 111: 273-7
  7. ↑ Meyer G. Fibrinolysis for patients with intermediate-risk pulmonary embolism. NEJM 2014; 370(15): 1402-1411
  8. ↑ Chatterjee. S et al. Thrombolysis for pulmonary embolism and risk of all-cause mortality, major bleeding, and intracranial hemorrhage: a meta-analysis. JAMA 2014; 311(23):2414-21. PubMed ID: 24938564.
  9. ↑ Thrombolysis_in_Pulmonary_Embolism_Metanalysis#Outcomes
  • Circulation. 2011 Apr 26;123(16):1788-830
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