(^128) Medical-Surgical Nursing Demystified
it lodges in one of the arteries. Depending on the size of the artery that the embo-
lus lodges in, a section of lung will have no blood supply and alveolar function
will suffer. As blood supply to an area of the lung diminishes, alveoli collapse,
causing atelectasis.
PROGNOSIS
A small area of atelectasis will allow for resolution and return to normal function
of the rest of the lung tissue. A large embolus at or near the main pulmonary artery
may be fatal. Patients may need to take ongoing anticoagulants if they have repeat
episodes or emboli or have an underlying clotting disorder.
HALLMARK SIGNS AND SYMPTOMS
- Sudden difficulty breathing (dyspnea) happens when the clot suddenly lodges
in the artery - Heart rate greater than 100 beats per minute (tachycardia)
- Respiration greater than 20 breaths per minutes (tachypnea) as the body attempts
to get more oxygen - Chest pain due to clot presence and area of atelectasis
- Coughing with blood-tinged sputum (hemoptysis)
- Crackles (rales) heard near area of clot
INTERPRETING TEST RESULTS
- Chest x-ray may show dilated pulmonary artery or pleural effusion.
- Lung scan shows ventilation-perfusion mismatch.
- Helical CT scan will show clot in pulmonary arteries.
- Pulmonary angiography will show presence of clot.
- Arterial blood gases may show decreased oxygen (PaO 2 ) and carbon diox-
ide (PaCO 2 ), depending on the size of the clot. - D-dimer will be positive when a thromboembolic event has occurred.
- Lower extremity ultrasound is often done to test for presence of thrombus.