Diagnosis and Management of Pulmonary Embolism

Venous ultrasonography:

Establish the presence of DVT

Contrast phlebography:

Rarely obtained

Objectives:
  • Achieve the following objectives with minimal side effects and inconvenience.
  • Risk Stratification.
  • Prevent death from PE.
  • Prevent post-thrombotic syndrome.
  • Prevent recurrent PE or VTE.

Death prevention
  • Oxygen supplementation.
  • Pain relief.
  • Temporary mechanical ventilation.
  • Inotropic agents.
  • Anticoagulation.
  • Thrombolytic therapy.
  • Surgical Embolectmy.

Anticoagulants:
  • Heparin
  • LMWH
  • Vitamin K antagonists (warfarin)
  • Hirudin
  • Pentasaccharide
  • Oral small-molecule direct thrombin inhibitor

Established Anticoagulants:
  • Initial treatment with heparin is necessary.
  • Induction period with heparin therapy for 10 days and can be reduced to 5 days.
  • LMWH can replace heparin and is now treatment of choice.
  • Optimal therapeutic range with warfarin is an INR of 2.0 to 3.0.
  • Continued treatment following hospital discharge is necessary.
  • Optimal duration of warfarin therapy still to be established.

LMWH: A Major Advance:
  • Weight-adjusted subcutaneous dosing predictable.
  • Once-daily subcutaneous dosing effective in DVT.
  • Treatment of PE effective and safe.
  • Less osteopenia than UFH.
  • Less HIT than UFH.
  • Outpatient treatment effective and safe.
Factors That May Influence Duration of Oral Anticoagulation:

Shorter Course

Bleeding risk
Unstable anticoagulant response
Inconvenient anticoagulation
Fear of recurrence or bleeding

Longer Course

VTE presentation (eg, massive PE)
Recurrent VTE
Poor cardiopulmonary reserve
Severe post-thrombotic syndrome
Thrombophilia


Potential Indications for Indefinite Anticoagulant Therapy:
  • Inherited Thrombophilia: AT (= antithrombin), protein C and S deficiency
  • Antiphospholipid syndrome.
  • Recurrent idiopathic VTE.
  • Malignancy.
  • Thromboembolic pulmonary hypertension.

New Anticoagulants for Treatment of DVT:
  • Hirudin (recombinant;lepirudin) is effective for treating thrombosis associated with HIT.
  • The new oral small-molecule direct thrombin inhibitor appears promising in multiple clinical trials.
  • Pentasaccharide has been evaluated in phase 2 studies and is being tested in phase 3 studies.

Fibrinolysis:
Exogenously administered drugs:
  • Streptokinase - bacterial product - continuous use - immune reaction
  • Urokinase - human tissue derived - no immune response (best for PE in Egypt)
  • Tissue plasminogen activator (tPA) - genetically cloned - no immune reaction – (EXPENSIVE)

N.B: Angikinase( 500,00 I.U ) Available in Egypt


Management Strategy and Prognosis for Pulmonary Embolism (MAPPET):
  • 719 patients without carcinogenic shock
  • 169 received thrombolytic therapy: 30-day mortality 4.7%; recurrent PE 7.7%; major bleeding 21.9%
  • 550 received heparin: 30-day mortality 11.1%; recurrent PE 18.7%; major bleeding 7.8%

Randomized Trial of Caval Interruption:
  • Initial benefit in preventing PE offset by excess of recurrent DVT in the longer term in the absence of anticoagulant.
  • Therefore, caval filter not recommended for this patient population in the long term.

Pulmonary Embolectmy:
  • Can be life saving in patients with massive PE.
  • In consecutive series of 96 patients, mortality was 37% (Meyer et al, 1991).
  • Cardiac arrest and associated cardiopulmonary disease were independent predictors of death.
  • Elective pulmonary embolectmy was life saving in selected patients with chronic thrombo-embolic pulmonary hypertension (Moser et al, 1990).

Recommended Treatment of Acute PE:
Massive PE with shock or syncope.
  • Thrombolysis or surgery.
    Major PE with right-ventricular dysfunction.
  • Thrombolysis (Goldhaber).
    Major PE without right-ventricular dysfunction.
  • Anticoagulants.
    Minor PE.
  • Anticoagulants

Back