Pulmonary embolism - is clogging blood clots in the lung arteries or their branches.Thrombotic process first developed in the pelvic veins (mainly in the myometrium of uterine body and the parameters of the uterus, in the peritoneum) or the lower extremities.
Pulmonary embolism is more common in people with developmental defects of the heart valves in patients with distinct disturbances in the functioning of the cardiovascular system.The likelihood of developing this disease as a complication are patients in the acute postoperative period, especially after interventions on the small pelvis (laporatomiya of Pfannenstiel, gisteektomiya, appendectomy, etc.) and the organs of the digestive system.A large percentage of risk are patients suffering from thrombophlebitis fletbotrombozami and all sorts of locations.
Pulmonary embolism causes
Pulmonary embolism is a relatively common pathology of the cardiovascular system.On average, reveal one case per 1,000 people per year.
thromboembolism pulmonary artery branches are mainly found in the elderly.At the heart of thromboembolism is the process of thrombosis.He contributes to the so-called triad of Virchow (three factors): increased blood clotting or hypercoagulable with inhibition of fibrinolysis;endothelial damage vessel walls;poor circulation.
source thrombus formation in this disease primarily serve leg veins.In the second place, the right atrium of the heart and the right departments, and venous thrombosis of the upper extremities.Pregnant women are more likely to develop venous thrombosis, as well as women who have a long enough period of time make OK (oral contraceptives).Patients also have thrombophilia risk of pulmonary embolism.
When endothelial damage vessel walls exposed subendothelial zone, because of what begins to rise blood clotting.Causes damage to the vascular walls are being damaged during heart surgery or blood vessels (catheter insertion, stents, filters, prosthetics large veins, etc.).Not a small role in the damage of vascular endothelium belongs bacterial and viral infections (for inflammation leukocytes adhere to the endothelium, thereby causing damage to it).
Infringement occurs when blood circulation: varicose veins;destruction of veins valve apparatus after suffering phlebothrombosis;vascular compression of cysts, bone fragments at fractures, tumors of various etiologies, pregnant uterus;in violation of the venous-muscle pump.Hemolytic diseases such as polycythemia vera (increase in the number of red blood cells and hemoglobin), digidratatsiya, polycythemia, Dysproteinemia, increased fibrinogen levels, contribute to increased blood viscosity, which, in turn, slows her bloodstream.
high risk of thromboembolic pulmonary artery branches are men: obese, having a cancer with genetics on the development of varicose veins, sepsis patients suffering from antiphospholipid syndrome (a process characterized by the formation of antibodies to platelets), leading a sedentary lifestyle.
Contributing factors are: smoking, overweight, use of diuretics, wearing a long catheter into the vein.
Pulmonary embolism symptoms
Tromboembolizatsiyu pulmonary branches located cause blood clots in the vein attached to its wall in the region of its base (the floating nature of blood clots).When peeling off a blood clot is its current entering through the right heart into the pulmonary artery, the artery oblitiruya.The consequences will depend on the number and size emboli, and light from the reaction and the reaction thrombotic system.
pulmonary artery is divided into the following types: solid, in which affected more than half of the branches of the pulmonary vascular bed (embolism of the main arteries in the lungs, or pulmonary) and accompanied by a state of severe systemic hypotension or shock;submassive at which struck one third of bloodstream (embolism multiple segments of pulmonary arteries or more segments of the equity), along with symptoms of right ventricular heart failure;nonmassive at which the affected at least one third of the vascular bed of the pulmonary arteries (arteries distal embolism in the lung), with no symptoms or with minimal symptoms (pulmonary infarction).
embolism small sizes symptoms are usually absent.Large emboli also impair blood flow through the segments or even a fraction of the whole lung, because of what disturbed gas exchange and begins hypoxia.Responses in the pulmonary circulation is a narrowing of the blood vessels, which is why in the branches of pulmonary artery pressure starts to rise.Increases the load on the right ventricle of the heart due to the high vascular resistance, which causes vasoconstriction and obstruction.
Thromboembolism of small vessels of the pulmonary artery does not cause hemodynamic disorder, only 10% of cases secondary pneumonia and lung infarction.It can carry a non-specific manifestation of symptoms in the form of raising the temperature to subfebrile and cough.In some cases, symptoms may be absent.
Massive pulmonary embolism is characterized by acute right ventricular failure with the development of shock and a decrease in blood pressure below 90 mm Hg, which is not associated with cardiac arrhythmia, sepsis or hypovolemia.There may be shortness of breath, loss of consciousness and severe tachycardia.
When submassive pulmonary embolism, arterial hypotension was not observed, but in the pulmonary circulation pressure is moderately increased.At the same time there are signs of the work of the right ventricle of the heart with myocardial damage, indicating that hypertension in the pulmonary artery.
When nonmassive pulmonary thromboembolism symptoms erased or not, after a certain time (an average of 3-5 days) develops heart attack lung during breathing causes pain due to irritation of the pleura, fever up to 39 ° C or higher, cough, hemoptysis,and by X-ray examination revealed the typical shadows in the shape of a triangle.When listening to heart sounds determine the focus of the second tone of the pulmonary artery and the tricuspid valve, as well as systolic murmurs in these areas.It is considered to be a poor prognostic sign detection at askultatsii gallop rhythm and the splitting of the second tone.
diagnosis of pulmonary embolism
diagnosis of pulmonary embolism causes certain difficulties because of nonspecific symptoms and imperfect diagnostic tests.
Standard survey include: laboratory tests, electrocardiogram (ECG), chest X-ray study of the method.These methods of examination can be informative as to exclude other diseases (pneumothorax, myocardial infarction, pneumonia, pulmonary edema).
to specific and sensitive diagnostic methods embolism include: measurement of d-dimer, computed tomography (CT) of the chest, echocardiography, ventilation-perfusion scintigraphy, angiography of the pulmonary arteries and blood vessels, as well as ways to diagnose varicose and trombosticheskogo of the deep veins of the lowerextremities (ultrasound diagnosis using Doppler ultrasound, computed venography).
is important laboratory determination of the amount of d-dimer (fibrin degradation products), upon detection of an increased level of which is expected to begin development of thrombophilia (thrombotic events).But also increase of d-dimer can be observed in other disease states (purulent inflammation, tissue necrosis, etc.), because the highly sensitive method of diagnosis is not specific in the definition of PE.
instrumental method for diagnosing pulmonary thromboembolism using ECG often helps to identify pronounced sinus tachycardia, pointed P-tooth, which is a sign of an overloaded operation of the right atrium.A quarter of patients may experience symptoms of pulmonary heart, which are characterized by axis deviation to the right and syndrome Mack Ginna-White (the first abduction deep S-prong sharp Q-tooth and a negative T-tooth in the third abduction), right bundle branch block.
of the chest with the help of X-rays can detect signs of increased pressure in the pulmonary arteries, which are the nature of thromboembolic (high position of the diaphragm in the affected area, the increase in right heart, pulmonary expansion descending artery to the right, a partial depletion of vascular pattern).
During the echocardiogram reveals an extension of the right ventricle, pulmonary artery hypertension symptoms, in some cases, detect blood clots in the heart.Also, this method may be useful for identifying other cardiac pathologies.For example, a patent foramen ovale, in which there may be hemodynamic disorder that is the cause of paradoxical pulmonary embolism.
Spiral CT detects it clots in the pulmonary arteries and branches.During this procedure, the patient is injected contrast agent, then the sensor is a rotation around the patient.It is important to hold your breath for a few seconds, to clarify the location of the thrombus.
Uzi peripheral veins of the lower limbs helps to detect blood clots, which are often the cause of venous thromboembolism.Compression can be applied ultrasound, which is obtained when a cross section of the lumen of the arteries and veins and generate a sensor pressing on the skin in the area of the veins in which blood clots in the presence of the lumens is not reduced.Also they can use Doppler ultrasound, in which the blood flow rate is determined by the Doppler effect in the blood vessels.Reducing speed is a sign of the presence of a blood clot.
pulmonary vascular angiography seems most accurate method for diagnosing pulmonary embolism, but this method is invasive and has no advantage over CT.Symptoms of pulmonary embolism of a thrombus is considered contours and sharp break branch of the pulmonary artery.
Pulmonary embolism treatment
Treatment of patients with pulmonary embolism should be done in an intensive care setting.
When cardiac arrest resuscitation produce it.In the case of hypoxia using a mask or nasal cannula for oxygen therapy.In certain cases, it may require mechanical ventilation.To increase the blood pressure in arteries is performed by intravenous injection of adrenaline, dopamine, dobutamine, and brine.
With a high likelihood of developing this condition is prescribed anticoagulation therapy with prescription drugs to reduce blood viscosity and reduce the formation of blood platelets.
Apply unfractionated heparin intravenously, dalteparin sodium, low molecular weight heparin subcutaneously or Fondaparinux.
dosage of heparin is selected based on the weight of the patient and determining the APTT (activated partial thromboplastin time).A solution of sodium heparin 20,000 units / kg per 400 ml saline.solution.Initially injected jet 80 U / kg were infused after 18ed / kg / hr.After 4-6 hours APTT is determined, correction is performed again after every three hours until the desired level of APTT.
In most cases, carried out with the injection of subcutaneous low molecular weight heparin, because they are more convenient and safer to use than intravenous infusion.
low molecular weight heparin enoxaparin shows (1 mg / kg twice daily), Tinzaparin (175 U / kg 1 time per day).At the beginning of therapy with anticoagulants warfarin shows scheduled (5 mg once a day).After the end of anticoagulant therapy receiving Varfamina continue for three months.
in the treatment of pulmonary embolism plays an important role reperfusion therapy, in which the main objective is to remove the blood clot and the establishment of normal blood flow in the pulmonary arteries.Such treatment is administered to patients at high risk.Assign streptokinase with a loading dose of 250,000 units for half an hour, after 100,000 units per hour during the day.Can be applied in a dosage scheme express 1.5 million units for two hours.Also prescribed urokinase (3 million units for two hours) or alteplase (100 mg within two hours, or 0.5 mg / kg of patient body weight over 15minutes).Dangerous problem of this thrombolytic therapy is bleeding.Extensive bleeding develops in 15% of cases, of which 2% ending stroke.
thrombectomy (surgical removal of the blood clots) consider alternative treatment of pulmonary embolism at high risk when anticoagulant and thrombolytic therapy is contraindicated.With this installation method produces cava filters, which themselves represent some of the strainers.These filters capture thrombi from the vascular wall and not allow them to penetrate into the pulmonary artery.This filter is inserted through the skin into the internal jugular vein or the femoral fixing below the renal veins.
Pulmonary embolism Emergency
If you suspect signs of pulmonary thromboembolism, which may be accompanied by severe pain in the chest, coughing, coughing up blood, fainting, shortness of breath, high fever, you must immediately call an ambulance detailexplaining the symptoms of the patient.Before the arrival of the ambulance the patient is desirable to accurately put on a horizontal surface.
When pulmonary embolism emergency care in the prehospital make the appointment of a strictly horizontal position of the patient;Fentanyl anesthesia (0.005%) with 2 ml 2 ml of 0.25% droperidol or Analgin 3 ml of 50% promedol with 1 ml of 2% intravenously;intravenous heparin bolus dosage unit 10000;at the expressed signs of respiratory arrest conduct therapy of respiratory failure;for violations of the heart rate determined by listening patient, the therapy to establish a normal heart rhythm and prevention of arrhythmia;when clinical death is carried out resuscitation measures nature.
In severe or moderate pulmonary thromboembolism for infusion therapy requires urgent introduction of a catheter into a central vein.
In acute heart failure Lasix administered 5-8 ml of 1% w / w, with a strong dyspnea promedol 2% at a dosage of 1 ml / in.
For the use of oxygen therapy Eufillin 10 ml 2.5% intravenous (does not apply to high blood pressure!).
By reducing blood pressure subcutaneously Kordiamin 2 ml.
If pain with thromboembolic pulmonary artery branches flows together with the collapse, then intravenously administered Norepinephrine 1ml 0.2% glucose in 400 ml at 5 ml / min while controlling blood pressure.You can also apply Mezaton 1 ml / in, jet, slow, or corticosteroids (prednisolone 60 mg or 100 mg of hydrocortisone).
hospitalization is shown in the department with intensive therapy.
Pulmonary embolism consequences
When pulmonary embolism prognosis is usually not entirely favorable.
consequences of massive pulmonary embolism can be fatal.In these patients, sudden death can occur.
If pulmonary infarction occurs destruction of his land with the development of inflammation in the dead hearth.Also, when this kind of pathology may evolve pleuritis (inflammation of the outer shell of the lungs).Often lead to respiratory failure.