lung and airway disorders
Pulmonary Embolism (PE)
Prevention of Pulmonary Embolism
Because pulmonary embolism can be dangerous and difficult to treat, doctors try to prevent blood clots from forming in the veins of people at risk. In general, people, particularly those who are prone to clotting, should try to be active and move around as much as possible. For example, when traveling on an airplane for a long period, people should try to get up and move around every 2 hours. Doctors select the anticoagulants, physical prevention measures, or combination of measures depending on the reason the person is at risk of pulmonary embolism and the person's underlying health status. For certain people, an anticoagulant medication (also called a blood thinner) is given, most oftenheparin. Heparincomes in two forms: Unfractionated Low molecular weight Unfractionatedheparinand low molecular weightheparinappear equally effective.Heparinis the most widely used medication for reducing the likelihood of clots forming in calf veins after any type of major surgery, especially surgery on the legs. Low molecular weightheparinis more predictable than the unfractionated form ofheparinand is commonly used for prevention of clots in people undergoing surgery that has a high risk of causing clots, such as hip or knee replacement. Small doses ofheparin, either unfractionated or low molecular weightheparin, are injected just under the skin, usually within 6 to 12 hours after surgery. Ideally, additional doses are given until the person is up and walking again (and sometimes longer). People who are hospitalized and at high risk of developing pulmonary embolism (such as those with heart failure, immobility, critical illness or obesity, or who have had clots in the past) benefit from small doses ofheparineven if they are not undergoing surgery. Low-doseheparindoes not increase the frequency of severe bleeding complications, butheparincan increase minor oozing of blood from wounds. Warfarin,an anticoagulant given by mouth, can be used for people at risk of pulmonary embolism. It is used much less commonly now because people need regular blood tests to monitor the effect ofwarfarin,warfarininteracts with many drugs, foods, and supplements that people may be taking, and newer medications are safer and more effective. Direct oral anticoagulantssuch as ,rivaroxaban,apixaban,edoxaban, anddabigatraninhibit the formation of substances that enhance the body’s production of clots. These medications are effective in prevention and in general are safer thanwarfarin. Nonetheless,warfarinis still considered the best choice for some people such as those with metallic heart valves. For people who have undergone surgery—especially older people—the risk of clot formation can be reduced by Using intermittent air compression devices or wearing elastic compression stockings Doing leg exercises Getting out of bed and becoming active as soon as possible Intermittent air compression devicesare inflatable devices that go over the lower legs and inflate and deflate to provide external pressure to keep blood moving in the legs. However, these devices alone are inadequate to prevent clot formation in people who have undergone certain high risk surgeries such as hip or knee replacement surgery. Elastic compression stockingsprovide steady pressure on the blood vessels of the legs to keep blood flowing. They are likely less effective than intermittent compression devices but still may be helpful in reducing the risk of blood clots in the legs. Doing leg exercises and getting out of bed also help keep blood flowing in the legs. When people who are at high risk of developing pulmonary embolism cannot take anticoagulants due to a high risk of bleeding, a(called an inferior vena cava filter) may be placed inside a large vein between the heart and the inferior vena cava, which returns blood to the heart from the lower part of the body. A filter can trap emboli, preventing them from reaching the lungs. 