PE

PULMONARY EMBOLISM

PULMONARY CIRCULATION

ETIOLOGY

  • Obstruction of the pulmonary artery or its branches by a thrombus:

    • Originates from the venous system or the right side of the heart.

  • Thrombotic:

    • Most common type of pulmonary embolism (PE).

    • Frequently arises from lower extremities, such as Deep Vein Thrombosis (DVT).

  • Non-Thrombotic:

    • Fat emboli.

    • Gas (air) emboli.

    • Foreign body emboli (e.g., amniotic fluid).

GENERAL RISK FACTORS FOR PE

  • High Risk:

    • Atrial fibrillation/flutter

    • Cardiac disease

    • Bed rest exceeding 3 days

    • Myocardial Infarction (MI) in the last 3 months

    • History of stroke

  • Moderate Risk:

    • Long flight or road trip

    • Joint replacement surgery

    • Joint surgery (knee)

    • Hypertension (HTN)

    • Diabetes Mellitus (DM)

    • Lower extremity fracture

    • Hormone Replacement Therapy (HRT)

    • Advanced age

    • History of Venous Thromboembolism (VTE)

    • Oral contraceptives

    • Pregnancy

    • Spinal cord injury

    • Cancer

    • Obesity

VIRCHOW’S TRIAD

  • Components:

    • Endothelial Damage:

    • Causes: Surgery, catheter placement, trauma, smoking, hypertension, hereditary coagulopathies.

    • Hypercoagulability:

    • Factors include cancer and chemotherapy, HRT/oral contraceptives, pregnancy, obesity, immobilization, polycythemia, dehydration, varicose veins, and heart/kidney disease.

    • Venous Stasis:

    • Conditions that hinder normal blood flow can result in pooling and increase clot formation risk.

INHERITED CLOT RISK FACTORS

  • Each factor influences different clotting aspects, raising the risk for clot formation:

    • Protein C and S deficiency

    • Prothrombin gene mutation

    • Factor V Leiden

    • Antithrombin III deficiency

PULMONARY EMBOLUS

PATHOPHYSIOLOGY: HEMODYNAMIC EFFECTS

  • Pulmonary Artery Obstruction:

    • Causes increase in Pulmonary Artery (PA) Pressure.

    • Leads to increased Right Ventricular (RV) Afterload.

    • Results in RV Dilation.

    • Septal displacement into the Left Ventricle (LV).

    • Affected by:

    • Decrease in RV output.

    • Decrease in LV Preload.

    • Decrease in overall cardiac output, leading to tissue edema and hypotension.

    • Consequences include strain on the right side of the heart, back-up of blood, and lung tissue without blood supply from the embolus.

PATHOPHYSIOLOGY: PULMONARY EFFECTS

  • Decreased Blood Flow:

    • Causes alveolar deadspace (ventilation without perfusion).

    • Leads to lack of gas exchange in affected areas, resulting in pulmonary shunting and hypoxemia.

PATHOPHYSIOLOGY: MASSIVE PE (SADDLE)

  • Clinical Presentation:

    • Severe dyspnea.

    • Cyanosis.

    • Sustained hypotension (SBP < 90 mmHg for 15 minutes).

    • RV dysfunction.

    • Potential for pulselessness and shock, occurring in 5-10% of PE cases.

PATHOPHYSIOLOGY: SUB-MASSIVE PE

  • Details:

    • Acute presentation without sustained hypotension.

    • RV dysfunction with preserved blood pressure.

    • Accounts for 20-25% of PE cases.

PATHOPHYSIOLOGY: LOW-RISK PE

  • Characteristics:

    • Lacks major clinical presentation typical of massive/sub-massive PE.

    • RV is not dysfunctional.

    • Represents 70-75% of PE cases.

SIGNS AND SYMPTOMS

  • Anxious and restless demeanor.

  • Hemoptysis (coughing up blood).

  • Rales (crackles in lung sounds).

  • Loud S2 heart sound.

  • Several unspecified symptoms may exist.

DIAGNOSIS

  • D-dimer:

    • A protein byproduct resulting from clot breakdown.

    • Levels greater than 500 ng/mL indicate high suspicion for PE.

  • Arterial Blood Gas (ABG):

    • Measures gas exchange efficiency.

  • Spiral CT and V/Q Scan:

    • Advanced imaging techniques for diagnosis.

  • Pulmonary Angiogram:

    • Gold standard for visualizing pulmonary arteries.

  • Ultrasound for DVT Detection:

    • To find deep vein thrombosis as a source.

TREATMENT: NURSING MANAGEMENT

  • Administration of Oxygen.

  • Cardiac monitoring to assess heart function.

  • Maintaining IV access and active fluid administration.

  • Close monitoring of anticoagulation therapy.

  • Pain management strategies as needed.

TREATMENT: ANTICOAGULATION

  • General Notes:

    • Anticoagulation therapy is essential before invasive procedures unless the patient is hemodynamically unstable.

  • Heparin:

    • Monitor activated Partial Thromboplastin Time (aPTT).

  • Warfarin:

    • Monitor International Normalized Ratio (INR); therapeutic range is specified.

    • Overlap therapy with Heparin for 4 days.

  • Direct Oral Anticoagulants (DOACs):

    • Examples include Apixaban (Eliquis) and Rivaroxaban (Xarelto).

  • Fibrinolytic Therapy:

    • Administered for massive PE using tPA and Heparin.

QUESTION:

  • Antidotes for Anticoagulants:

    • Heparin: [specific antidote information].

    • Warfarin: [specific antidote information].

    • DOACs: Idarucizumab, Andexanet alfa, and Ciraparantag.

    • Fibrinolytics: Aminocaproic acid (Amicar) and Tranexamic acid (TXA).

  • Importance of Knowing Antidotes:

    • Essential for emergency reversal of anticoagulation.

  • Context of Use:

    • Understanding when a nurse might need to use them.

TREATMENT: POST-SURGICAL MANAGEMENT

  • Risk Level Management:

  • Low Risk:

    • Minor surgery, under 40 years.

    • No DVT risk factors present.

    • Strategies: Early mobilization and mechanical aids.

  • Moderate Risk:

    • Major surgery, over 40 years with no DVT risk factors.

    • Strategies: Early mobilization, mechanical aid, and possible Heparin or Enoxaparin use.

  • High Risk:

    • Major surgery, over 40 years with DVT risk factors.

    • Necessitates mechanical aid and anticoagulation (Heparin/Enoxaparin).

    • High-risk surgeries such as hip or knee arthroplasty should involve mechanical aids and anticoagulation management.

TREATMENT: THROMBECTOMY INTERVENTIONS

  • Thrombectomy:

    • Catheter aspiration thrombectomy: removal of blood clots using suction.

    • Mechanical thrombectomy: breaking blood clots into smaller pieces for removal.

TREATMENT: EMBOLECTOMY

  • Indications:

    • For massive PE with hemodynamic instability.

    • When thrombolytic therapy is contraindicated.

    • Surgical removal of the clot is warranted in such scenarios.

TREATMENT: INFERIOR VENA CAVA FILTER (IVC)

  • Indications:

    • For patients at high risk for recurrent PE.

    • Situations where chronic anticoagulation is contraindicated.

    • This approach reduces but does not fully eliminate PE risk.

  • Risks associated with IVC filters: [not specified in the transcript].

TREATMENT: PREVENTION

  • Best Management Practices:

    • Key strategy is preventing PE occurrence.

    • Avoid prolonged placement of IV catheters.

    • Use Low Molecular Weight Heparin (LMWH) for prevention.

    • Education:

    • Importance of ambulation and early mobilization for patients.

    • Use Sequential Compression Devices (SCDs) for non-ambulatory patients.

    • Encouragement for passive leg exercises.

    • Recommendations for leg positioning (feet resting on the floor).

    • In cases with known genetic factors, chronic, lifelong oral anticoagulation is advised.

COMPLICATIONS OF PE

  • Possible complications resulting from thrombolytic therapy include:

    • Pain.

    • Cardiogenic shock.

    • Chronic pulmonary hypertension.

    • Respiratory failure.

    • Potential for death as a critically severe outcome.

NURSING CONSIDERATIONS

  • [contents not specified in the transcript]