Pulmonary embolism

Medical quality assurance by Dr. Albrecht Nonnenmacher, MD at April 15, 2016
StartDiseasesPulmonary embolism

Pulmonary embolism (PE) is a dangerous blockage in an artery in or around the lungs. This condition can quickly lead to permanent damage or even death in patients, so it is considered a serious and urgent condition. Since PE is closely linked to deep vein thrombosis in many patients, some doctors describe the conditions jointly as venous thromboembolism.


Definition & Facts

The pulmonary arteries are among the most important blood conduits in the human body. They carry blood from the heart directly to the lungs where it is infused with oxygen. When a blockage develops in one of these arteries, it severely limits the supply of oxygen in the body. Since this element is absolutely essential for basic brain function and body functions, PE is often a life-threatening development that requires emergency treatment.

Symptoms & Complaints

The primary symptoms of pulmonary embolism result from lower levels of available oxygen in the bloodstream, including accelerated breathing, sudden increase in heart rate, and loss of mental faculties. Blockages in the pulmonary arteries can cause dizziness and loss of consciousness. Some patients also experience a sharp pain in their upper chest or develop a painful cough that may produce blood.

Prolonged cases of PE may result in a lack of oxygen throughout the entire body, particularly in the extremities. Some patients notice a blue discoloration on their fingers or toes, similar to some of the visible symptoms of hypothermia or altitude sickness.

In some cases, patients have a mild fever and sweat excessively even in temperate environments. PE can sometimes kill the patient within moments of producing any tangible warning signs, which leaves the patient and those nearby with little time to seek treatment.


The vast majority of embolism cases develop as a result of thromboses of the legs or pelvic vein. These conditions lead to the formation of blood clots, which can break free and move through the bloodstream towards the heart and lungs. There are many conditions that increase the risk of developing PE, especially those that limit movement. Pregnancy, injuries that require long term convalescence, cancer, and obesity can all lead to the development of this dangerous condition.

Individuals recovering from surgery are always at an elevated risk of developing clots, which is why post-operative recovery instructions often include limited exercises to encourage healthy blood flow. Hormone therapy can also alter the composition and texture of blood, which can also become a primary factor in the development of PE.

Some genetic disorders, like protein C deficiency and hyperhomocysteinemia, are also linked to the condition. Many people who develop PE suffer from several of these contributing factors simultaneously. While blood clots are the primary culprit in embolism cases, it is possible for pieces of fat, tumors or air bubbles to create a clog in the arteries as well.

Diagnosis & Tests

Even though PE is a well-known condition in the modern medical community, it is not easy to diagnose. Many of the visible symptoms are common ones that could be the result of a variety of health problems. For this reason, diagnosis is based on the patient's medical history as well as the results of a physical examination and lab tests.

A D-dimer test is one of the primary diagnostic techniques available when embolism is suspected. This test measures the amount of a certain chemical in the bloodstream that is released when a clot disintegrates. A high reading on the test indicates the possibility of an embolism.

Internal imaging technology, including ultrasounds and X-rays, often play a large part in immediate diagnosis during emergency situations. The examining doctor may also issue several other tests to make sure that there isn't another active issue that is causing the symptoms.

Treatment & Therapy

Treatment for PE depends on the severity of each patient's case, so there is no uniform cure for the condition. For those suffering from a minor blockage that is not life threatening, doctors often prescribe blood thinners which alter the chemistry of the blood to discourage clot formation and growth.

Fast-acting pharmaceutical treatments, called thrombolytic drugs, are also available for those with a severe embolism. These medicines create a high risk of internal bleeding in the patient, so they are only used when necessary. Due to the risks of certain medicine to pregnant women, an alternate treatment regimen is usually prescribed.

Patients suffering from deep vein thrombosis in the legs and who are unable to take blood thinning medicine effectively may need surgery to install a filter to prevent clots from traveling to the lungs. In rare cases of severe embolism, surgery to directly remove clots from pulmonary arteries may also be recommended.

Prevention & Prophylaxis

Patients who are identified as high risk for clot or embolism development are often prescribed blood thinners for daily use. This helps prevent clots from forming to begin with, which greatly reduces the risk of PE. There is a significant risk of developing multiple clots, so some people recovering from embolisms are given an anticoagulant medicine for temporary use.

Those recovering from surgery should follow their post-operative care guidelines carefully. In many cases, the guidelines include safe exercises that will help blood flow without aggravating the surgical wound. Prolonged periods of limited activity, like resting in a bed or chair, greatly increase the chances of clot development inside the blood vessels. Patients should consult their doctor about the risks associated with long distance travel in cars, planes and trains where opportunities for exercise are limited.

Compression stockings are another common preventative tool. They constrict the legs and encourage blood to flow faster through the tissue, which reduces the likelihood of clot development. Patients may also benefit from raising their legs on pillows while they sleep, or raising the base of their bed by several inches.