Pulmonary Embolism

Definition

Pulmonary embolism is a blockage in one of the pulmonary arteries in your lungs. In most cases, pulmonary embolism is caused by blood clots that travel to the lungs from the legs or, rarely, other parts of the body (deep vein thrombosis).

It can damage part of the lung due to restricted blood flow, decrease oxygen levels in the blood, and affect other organs as well. Large or multiple blood clots can be fatal.

Primary Cause(s)

Three primary influences predispose a patient to thrombus formation; these form the so-called Virchow triad, which consists of the following

Endothelial injury Stasis or turbulence of blood flow Blood hypercoagulability

Other Causes (Multifactorial)

Venous stasis leads to accumulation of platelets and thrombin in veins.

Concomitant hypercoagulability may be present in disease states where prolonged venous stasis or injury to veins occurs. Hypercoagulable states may be acquired or congenital.

Immobilization leads to local venous stasis by accumulation of clotting factors and fibrin, resulting in thrombus formation.

Surgical and accidental traumas predispose patients to venous thromboembolism by activating clotting factors and causing immobility. Pulmonary embolism may account for 15% of all postoperative deaths. Leg amputations and hip, pelvic, and spinal surgery are associated with the highest risk.

Other Causes (Multifactorial) Pregnancy - the incidence of thromboembolic disease in pregnancy

has been reported to range from 1 case in 200 deliveries to 1 case in 1400 deliveries

a family history of embolisms a history of heart attack or stroke obesity a sedentary lifestyle age over 60 years Estrogen-containing birth control pills have increased the occurrence

of venous thromboembolism in healthy women. The risk is proportional to the estrogen content and is increased in postmenopausal women on hormonal replacement therapy.

cancer

Pathophysiology

Signs and Symptoms

Shortness of Breath – most common anxiety clammy or bluish skin chest pain that may extend into your arm, jaw, neck, and shoulder fainting irregular heartbeat light-headedness rapid breathing rapid heartbeat restlessness spitting up blood weak pulse

Complications

Diagnosis/Tests

Pulmonary embolism can be difficult to diagnose, especially in people who have underlying heart or lung disease. For that reason, your doctor will likely order one or more of the following tests.

Diagnosis/Tests

D-dimer test – a clot-dissolving substance. High levels may suggest an increased likelihood of blood clots

ABG test - measures the amount of oxygen and carbon dioxide in your blood

Blood test to confirm if patient has a inherited clotting disorder

Diagnosis/Tests

Chest X-ray- this noninvasive test shows images of your heart and lungs on film. Although X-rays can't diagnose pulmonary embolism and may even appear normal when pulmonary embolism exists, they can rule out conditions that mimic the disease.

Diagnosis/Tests Ultrasound-A noninvasive test known as duplex

ultrasonography (sometimes called duplex scan, or compression ultrasonography) uses sound waves to check for blood clots in your thigh veins.

Diagnosis/Tests Spiral CT scan - this type of CT can detect

abnormalities within the arteries in your lungs with much greater precision than conventional CT scans. In some cases, contrast material is given intravenously during the CT scan to outline the pulmonary arteries.

Diagnosis/Tests Pulmonary angiogram This test provides a clear picture of the blood

flow in the arteries of your lungs. It's the most accurate way to diagnose pulmonary embolism, but because it requires a high degree of skill to administer and has potentially serious risks, it's usually performed when other tests fail to provide a definitive diagnosis.

One risk of this procedure is a temporary change in your heart rhythm. In addition, the dye may cause kidney damage in people with decreased kidney function.

Diagnosis/Tests

MRI-use radio waves and a powerful magnetic field to produce detailed images of internal structures. Because MRI is expensive, it's usually reserved for pregnant women (to avoid radiation to the fetus) and people whose kidneys may be harmed by dyes used in other tests.

Treatment Medications

Blood thinners (anticoagulants). These drugs prevent new clots from forming while your body works to break up the clots.

Heparin Clot dissolvers (thrombolytics). While clots

usually dissolve on their own, there are medications given through the vein that can dissolve clots quickly. Because these clot-busting drugs can cause sudden and severe bleeding, they usually are reserved for life-threatening situations.

Treatment Surgical Intervention

Clot removal. If you have a very large, life-threatening clot in your lung, your doctor may suggest removing it via a thin, flexible tube (catheter) threaded through your blood vessels.

Vein filter. A catheter can also be used to position a filter in the body's main vein — called the inferior vena cava — that leads from your legs to the right side of your heart. This filter can help keep clots from being carried into your lungs. This procedure is typically reserved for people who can't take anticoagulant drugs or when anticoagulant drugs don't work well enough or fast enough. Some filters can be removed when they are no longer needed.

Embolectomy - either catheter embolectomy and fragmentation or surgical embolectomy is reasonable for patients with massive pulmonary embolism who have contraindications to fibrinolysis or who remain unstable after receiving fibrinolysis.

Treatment Nursing Interventions

Prevent venous stasis. Encourage ambulation and active and passive leg exercises to prevent venous stasis.

Monitor thrombolytic therapy. Monitoring thrombolytic and anticoagulant therapy through INR or PTT.

Manage pain. Turn patient frequently and reposition to improve ventilation-perfusion ratio.

Manage oxygen therapy. Assess for signs of hypoxemia and monitor the pulse oximetry values.

Relieve anxiety. Encourage the patient to talk about any fears or concerns related to this frightening episode.

Discharge and Home Care Guidelines

After discharge, there are some guidelines that the nurse must teach the patient.

Prevent recurrence. The nurse should instruct the patient about preventing recurrence and reporting signs and symptoms.

Adherence. The nurse should monitor the patient’s adherence to the prescribed management plan and enforces previous instructions.

Residual effects. The nurse should also monitor for residual effects of the PE and recovery.

Follow-up checkups. Remind the patient about keeping up with follow-up appointments for coagulation tests and appointments with the primary care provider.