pulmonary embolism

Pulmonary embolism (PE)

Blockage of a pulmonary artery or one of its branches, usually by a blood clot originating in the venous system or right side of the heart.

Deep vein thrombosis (DVT)

Formation of a blood clot in a deep vein, commonly in the lower extremity.

Venous thromboembolism (VTE)

The combined term for DVT and pulmonary embolism.

Pathophysiology of PE

A clot may break loose from a deep vein, travel through the venous circulation and right side of the heart, and lodge in a pulmonary artery.

Virchow's triad

Three major factors contributing to clot formation

Venous stasis

Slowed or pooled blood flow in the veins, increasing the risk of clot formation.

Endothelial injury

Damage to the inner lining of blood vessels that can promote clot formation.

Hypercoagulability

Increased tendency of blood to clot.

Risk factors for PE

Prolonged immobility, older age, obesity, severe sepsis, trauma, surgery, pregnancy, heart failure, malignancy, arrhythmias, and hypercoagulable conditions.

Manifestations of PE

Sudden dyspnea, pleuritic chest pain, tachypnea, tachycardia, cough, hypotension, and possible hemoptysis.

DVT warning signs

Unilateral leg pain, warmth, swelling, or discoloration.

Classic PE warning signs

Sudden dyspnea and pleuritic chest pain accompanied by tachycardia or tachypnea in a patient with clotting risk factors.

D-dimer

Blood test that detects evidence of clot breakdown; a positive result does not independently diagnose PE.

Chest X-ray in PE

Helps evaluate other possible causes of symptoms but does not confirm or rule out PE by itself.

CT pulmonary angiogram (CTPA)

Imaging test used to visualize pulmonary blood vessels and evaluate for PE; IV contrast is generally used.

V/Q scan

Ventilation-perfusion scan that evaluates airflow and blood flow in the lungs; it may be used when CT contrast is unsuitable.

Ventilation (V)

Movement of air into and out of the lungs.

Perfusion (Q)

Blood flow through pulmonary capillaries.

PE prevention

Early ambulation, active leg exercises, sequential compression devices, and prescribed prophylactic anticoagulation for at-risk patients.

Prophylactic anticoagulation

Medication given to reduce the risk of blood clot formation in patients at increased risk.

Emergency management of PE

Prioritize oxygenation and ventilation, support circulation, establish IV access, monitor continuously, obtain ordered tests, and administer prescribed anticoagulation or thrombolytic treatment as indicated.

Anticoagulants

Medications that reduce further clot formation or clot extension; heparin does not directly dissolve an existing clot.

Thrombolytics

Medications that dissolve clots and may be used in selected severe or high-risk PE cases.

IVC filter

Device placed in the inferior vena cava to trap certain clots traveling from the lower body toward the lungs; it does not treat an existing PE.

Nursing priorities for PE

Support oxygenation, monitor hemodynamic status and neurological status, watch for bleeding during anticoagulant therapy, and recognize deterioration promptly.