Pulmonary embolism (PE) is an acute occlusion of the branches of the pulmonary artery thrombus in the veins of the systemic circulation.
Pulmonary embolism is up to 50% mortality in hospital cardiology departments of hospitals, it also is the main cause of death in postoperative patients. Sudden death in one third of cases due to pulmonary embolism. Die about 20% of patients with pulmonary embolism, and more than half of them in the first 2 hours after the onset of embolism.
The most common cause of pulmonary embolism are blood clots that have arisen in the deep veins and often in the deep veins of the lower extremities. Much less is blood clots in the veins of the pelvis, abdomen, upper extremities, the right heart. Contribute to the formation of blood clots bed rest, especially in patients with lung disease, myocardial infarction, surgery for hip fracture. And more often in patients with spinal cord injuries. Occasionally, pulmonary arterial thromboembolism may occur in healthy people who are forced for a long time position. For example, when flying on an airplane.
For the formation of a thrombus requires three conditions:
damage to the vessel wall
slowing of blood flow at this location
increase in blood clotting.
The wall of the vein can be damaged in inflammatory diseases, intravenous injections, trauma.
Conditions for the slowing of blood flow are caused by heart failure, prolonged forced position (bed rest, casts).
The reasons for increasing blood clotting are some hereditary disorders of blood coagulation, use of oral contraceptives, AIDS. Increased risk of blood clots in people with the second group of blood, pregnant women, patients with obesity.
The most dangerous blood clots, which are attached at one end to the vessel wall and the other, free, floating in the lumen of the vein. With a little effort: cough, sudden movement, straining, blood clot breaks off and with the blood flow through the vena cava, right atrium, right ventricle enters the pulmonary artery. Sometimes the clot is broken, hitting the artery walls and clogs the small branch vessels of the lungs.
Blockage of the pulmonary artery branches with a large number of blood clots leading to increased pressure in the vessels of the lungs. Increases the load on the right ventricle and congestive heart failure develops. The fall of the right ventricular pump function is insufficient blood flow into the left ventricle, decreasing the amount of blood that comes into the aorta and arteries - a sharp drop in blood pressure and shock. All this may be accompanied by right ventricular myocardial infarction, atelectasis (part wears lung tissue) in the lungs.
Depending on the volume of vascular lesions of the lungs pulmonary embolism can be:
massive - more than 50% of the vessels of the lungs, while the patient is losing consciousness, shock, drop in blood pressure, right ventricular insufficiency submassivnaya - from 30 to 50% of the vessels of the lungs - a patient's shortness of breath, normal blood pressure, right ventricular function is impaired to a lesser extent nonmassive - less than 30% is accompanied by shortness of breath, right ventricular function is not affected.
The manifestations of pulmonary embolism depend on the massiveness of the process, the state of the cardiovascular system and lungs. The most frequent manifestation of pulmonary embolism - shortness of breath and rapid breathing. Dyspnea arises suddenly. The patient feels better in the prone position. Chest pain has a different character. The patient may be severe pain or discomfort in the chest. Occasionally there is hemoptysis. You may see cyanosis - bluish color of the nose, lips, ears, or paleness. The lungs are auscultated wheezing, over an area of the heart - systolic murmur. The ECG reveals signs of acute cor pulmonale. On the echocardiogram are blood clots in the right heart and pulmonary arteries, signs of right ventricular dysfunction. On radiographs reveal changes in the lungs.
The most reliable method for diagnosing pulmonary embolism - ventilation-perfusion scintigraphy of the lungs, especially in the first day. This research vessels of the lungs with contrast agents. Apply even computed tomography and magnetic resonance imaging of light.
Treatment of pulmonary embolism.
All patients should be hospitalized in the intensive care unit. The patient is removed from the state of shock. Give oxygen through a nasal catheter. If necessary, anesthesia.
Achievement of modern medicine is the ability to dissolve a blood clot in the vessel. To do this, hold thrombolytic therapy. Intravenous drugs to dissolve blood clot (streptokinase, urokinase, tissue plasminogen activator). Then prescribe heparin to prevent the recurrence of thrombosis. Heparin was injected into a vein 7-10 days. Then hold up to 3-6 months treatment with drugs that prevent blood clotting increase (fenilin, sinkumar, warfarin) for mandatory control blood clotting.
Sometimes when plugging the main branches of the pulmonary artery is carried out the surgical removal of thrombus. Mortality in these operations is high, but lower than those without surgery.
When PE is sometimes repeated in the inferior vena cava filter is placed, called cava filter. It prevents the ingress of blood clots in the pulmonary artery.
Without treatment for pulmonary embolism kills about half of patients with timely proper treatment, deaths from pulmonary embolism is 2-8%.