Module 5 - Pulmonary Embolism

What is a pulmonary embolism (PE)?

A blockage of one or more pulmonary arteries, usually caused by a thrombus that originated in a deep vein of the leg or pelvis.

Where do most pulmonary emboli originate?

Deep vein thrombosis (DVT) of the lower extremities.

What is the most common cause of a PE?

Thromboembolism from a DVT.

What happens when a pulmonary artery becomes blocked?

Blood flow to part of the lung stops while ventilation continues.

What type of V/Q mismatch occurs in PE?

Dead space ventilation.

What is dead space ventilation?

Alveoli are ventilated but not perfused.

Why does hypoxemia occur in PE?

Blood cannot reach ventilated alveoli for gas exchange.

How does a PE affect the right ventricle?

It increases pulmonary vascular resistance, causing right ventricular strain.

What life-threatening complication can develop from a massive PE?

Obstructive shock.

What are Virchow's Triad?

Venous stasis, endothelial injury, and hypercoagulability.

What conditions cause venous stasis?

Prolonged immobility, surgery, paralysis, long-distance travel.

What causes endothelial injury?

Trauma, surgery, central venous catheters.

What causes hypercoagulability?

Cancer, pregnancy, estrogen therapy, inherited clotting disorders.

What are the major risk factors for PE?

DVT, surgery, immobility, cancer, pregnancy, oral contraceptives, smoking, obesity, previous VTE.

What is the hallmark symptom of PE?

Sudden onset dyspnea.

What type of chest pain is common with PE?

Sharp pleuritic chest pain.

Why does pleuritic chest pain occur?

Infarction or irritation of the pleura.

What respiratory rate is commonly seen?

Tachypnea.

Why does tachycardia occur?

The body attempts to compensate for decreased oxygen delivery.

What type of cough may occur?

Dry cough or hemoptysis.

Why can hemoptysis occur?

Pulmonary infarction damages lung tissue.

What lung sounds are often heard in PE?

Often normal or minimally abnormal.

Why can lung sounds be normal despite severe symptoms?

The problem is perfusion, not airway obstruction.

What oxygen saturation finding is common?

Hypoxemia.

What cardiovascular finding may occur with a massive PE?

Hypotension.

What neck vein finding suggests right heart strain?

Jugular venous distention (JVD).

What skin finding may occur?

Cyanosis.

What symptom may be the only clue in older adults?

Acute unexplained dyspnea.

What laboratory test is commonly elevated with PE?

D-dimer.

What does an elevated D-dimer indicate?

Recent clot formation and breakdown.

Can an elevated D-dimer alone diagnose PE?

No.

When is D-dimer most useful?

To rule out PE in low-risk patients.

What is the gold standard imaging test for PE?

CT pulmonary angiography (CTPA).

When may a V/Q scan be used instead of CT angiography?

Contrast allergy, pregnancy, or renal failure.

What ECG finding is commonly seen?

Sinus tachycardia.

What classic ECG pattern may occur?

S1Q3T3 (uncommon).

Why may troponin be elevated in PE?

Right ventricular strain.

What imaging test may identify the source of the embolus?

Venous Doppler ultrasound of the legs.

What bedside test may show right ventricular strain?

Echocardiogram.

What is the immediate treatment priority for suspected PE?

Administer oxygen and notify the provider immediately.

What is the first-line medication for most PEs?

Anticoagulants.

Which anticoagulants are commonly started initially?

Heparin or low-molecular-weight heparin (enoxaparin).

Which oral anticoagulants may be used long term?

Apixaban, rivaroxaban, dabigatran, warfarin.

What is the purpose of anticoagulants?

Prevent clot extension and formation of new clots.

Do anticoagulants dissolve existing clots?

No.

Which medications dissolve clots?

Thrombolytics (alteplase).

When are thrombolytics indicated?

Massive PE with hemodynamic instability.

What serious risk accompanies thrombolytics?

Major bleeding.

When may surgical or catheter embolectomy be performed?

If thrombolytics are contraindicated or ineffective.

When is an IVC filter indicated?

When anticoagulation cannot be given or recurrent emboli occur despite therapy.

What oxygen therapy is commonly needed?

Supplemental oxygen to maintain adequate saturation.

When may mechanical ventilation become necessary?

Respiratory failure or severe hypoxemia.

What is the nurse's highest priority during acute PE?

Assess ABCs and support oxygenation.

What respiratory assessments are priorities?

Respiratory rate, SpO₂, work of breathing, lung sounds.

What cardiovascular assessments are priorities?

Heart rate, blood pressure, signs of shock.

Why should mental status be monitored?

Hypoxemia may cause confusion or decreased LOC.

Why should activity initially be limited?

To reduce oxygen demand until stable.

What should the nurse monitor while the patient receives anticoagulants?

Bleeding.

What bleeding findings should be assessed?

Hematuria, melena, bruising, epistaxis, bleeding gums.

Which laboratory values are monitored with unfractionated heparin?

aPTT.

Which laboratory value is monitored with warfarin?

INR.

What patient teaching is essential for anticoagulants?

Take exactly as prescribed and report signs of bleeding.

What should patients taking warfarin know about vitamin K?

Maintain a consistent intake of vitamin K foods.

What discharge teaching reduces future PE risk?

Early ambulation, leg exercises, hydration, smoking cessation, medication adherence.

Why should hospitalized patients receive DVT prophylaxis?

To prevent pulmonary embolism.

Which preventive measures reduce DVT risk?

Sequential compression devices (SCDs), anticoagulants, ambulation, leg exercises.

NCLEX: PE causes ventilation without ________.

Perfusion.

NCLEX: PE creates dead space or shunt?

Dead space.

NCLEX: What is the gold standard diagnostic test for PE?

CT pulmonary angiography.

NCLEX: What is the first-line treatment for most pulmonary emboli?

Anticoagulation.

NCLEX: Do anticoagulants dissolve existing clots?

No.

NCLEX: Which medication dissolves a clot?

Alteplase.

NCLEX: Which assessment finding is most characteristic of PE?

Sudden unexplained dyspnea.

NCLEX: Which complication of PE is immediately life-threatening?

Obstructive shock.

NCLEX: What are the nursing priorities for PE?

Maintain oxygenation, administer anticoagulants, monitor for shock and bleeding.