Bronchopulmonary embolism. Pulmonary embolism. Risk factors for pulmonary embolism

Pulmonary embolism is a complication that is often seriously life-threatening. Pulmonary infarction is a consequence of blockage of the pulmonary artery. This condition manifests itself as a sudden attack of suffocation, breathing becomes shallow and rapid.

Sometimes there is a dull pain in the chest and severe anxiety. Fever and cough may also occur. The symptoms of a pulmonary infarction are quite similar to those of a myocardial infarction.

Causes of pulmonary embolism and pulmonary infarction

Pulmonary embolism is formed when there is a sudden closure of the pulmonary artery duct or its branches. The pulmonary artery, which is divided into left and right, ensures the delivery of venous blood from the right ventricle of the heart to the lungs, where the blood releases unnecessary gases and is saturated with oxygen.

Lung tissue under...

Blockage in the pulmonary artery, as a rule, is a consequence of deep vein thrombosis, mainly in the lower extremities. For a clot to form, the clot must separate from the walls of the veins and travel through the bloodstream to the right side of the heart and then to the pulmonary artery. If pulmonary embolism occurs during deep vein thrombosis, it is referred to as venous thromboembolism.

Pulmonary embolism accounts for about 7% of hospital deaths in the United States. The mortality rate from this disease reaches 30%.

Increased risk of pulmonary artery blockage occurs in people who have a tendency to form blood clots in blood vessels, i.e. those who:

• lie in bed for a long time: this is a very significant risk factor for deep vein thrombosis and pulmonary embolism, so doctors always try to get patients back on their feet after surgery as quickly as possible;
• suffer from heart muscle failure or a blood disease that facilitates the clotting process;
• are obese;
• have undergone major surgery, especially in the lower extremities and abdominal area;
• suffer from malignant cancer;
• have a common infection;
• have recently suffered a severe injury, especially multiple organ trauma or a fracture of the pelvis, the nearest part of the femur and other long bones of the lower extremities, spinal cord injury associated with paralysis of the lower extremities and prolonged immobility;
• have an increased tendency to form blood clots, congenital or acquired;
• suffer from Crohn's disease or ulcerative colitis;
• have a family history of pulmonary embolism;
• have varicose veins of the lower extremities (varicose veins themselves are not a risk factor, but they increase the impact of other risk factors for thrombosis).

Additionally, the risk increases if these factors occur in a person over 40 years of age. In addition, pregnant women and women in the postpartum period are a special risk group. An increase in blood clotting can also occur in persons taking medications, as well as hormonal methods of contraception (especially in combination with smoking). The risk increases when using hormone replacement therapy (pills) or taking selective estrogen receptor modulators, for example, tamoxifen, raloxifene.

Until recently, pulmonary embolism was divided into massive, submassive and non-massive. For some time now, a new and improved classification of this disease has been in use. Embolism is now classified as a high-risk disease (the risk of death is estimated to be greater than 15%) and a low-risk disease. Low-risk embolism is divided into intermediate-risk conditions, when the risk of death is 3-15%, and low-risk pulmonary embolism, with a probability of death below 1%.

In addition to blood clots, cause pulmonary artery blockage can also:

• amniotic fluid (for example, after premature placental abruption);
• air (for example, when a catheter is inserted into a vein or removed);
• adipose tissue (for example, after a long bone fracture);
• tumor masses (for example, with kidney cancer or stomach cancer);
• foreign body (for example, material used for vascular embolization).

Symptoms and diagnosis of pulmonary embolism and pulmonary infarction

Pulmonary embolism manifests itself, as a rule, through sudden severe chest pain (in about half of patients), shortness of breath (in more than 80% of patients), and accelerated breathing (in 60% of patients). In addition, sometimes there are problems with consciousness or even fainting (short-term loss of consciousness). Some patients experience increased heart rate (above 100 beats per minute).

In more severe cases, when a large branch of the artery is blocked, a drop in blood pressure (hypotension) and even shock can occur. Sometimes a cough is observed (quite dry in case of embolism and with bloody discharge in case of pulmonary infarction). In addition, during pulmonary embolism, fever, hemoptysis (in 7%), sweating, and a feeling of fear may occur. If such signs occur, it is necessary to call an ambulance as quickly as possible.

Sometimes diagnosing an embolism is quite difficult, since the symptoms listed above also appear with other diseases, such as pneumonia or a heart attack. Symptoms can also be mild and this can be misleading. Meanwhile, pulmonary embolism is a life-threatening condition and requires strictly hospital treatment. Many people who have a pulmonary artery blockage die. In cases where death does not occur, the risk of re-embolism increases, such people should be constantly under the supervision of a doctor.

If clinical manifestations suggest pulmonary embolism, ultrasound examination of the veins of the lower extremities is also recommended. If this study reveals the presence of blood clots in the venous system of the lower extremities, this almost 100% confirms the diagnosis.

Pulmonary embolism must always be distinguished, first of all, from:

• lung diseases, i.e. asthma, chronic obstructive pulmonary disease (exacerbation), pleural pneumothorax, inflammation of the lungs and pleura, acute respiratory failure syndrome;
• diseases of the cardiovascular system, such as myocardial infarction, heart failure;
• neuralgia of the intercostal nerve.

Diagnosing pulmonary embolism is sometimes very difficult. The Wellsa test was created to help doctors. It is presented below. For the approval of each of the specified diseases a certain number of points is awarded:

• Previous history of deep vein inflammation or pulmonary embolism (1.5 points).
• Recent surgery or immobilization (1.5 points).
• Malignant tumor (1 point).
• Hemoptysis (1 point).
• Heart rate above 100 beats/min (1.5 points).
• Symptoms of deep vein inflammation (3 points).
• The likelihood of other diagnoses is lower than pulmonary embolism (3 points).
  • 0-1: clinical pulmonary embolism is unlikely;
  • 2-6: intermediate probability of clinical pulmonary embolism;
  • greater than or equal to 7: high probability of clinical pulmonary embolism.

Treatment of pulmonary embolism

The treatment method for pulmonary embolism depends on the severity of the disease. In the most severe cases associated with a high risk of death, it is used thrombolytic therapy or treatment with drugs that activate the dissolution of blood clots.

The most commonly used are alteplase or streptokinase. These drugs are administered intravenously during the acute phase of the disease. After their introduction, heparin is usually added, that is, the substance prevents blood clotting.

After stabilizing the patient's condition, another type of drug is given - acenocoumarol. This drug works by slowing the production of clotting factors in the liver. This leads to a decrease. This drug is then used continuously, sometimes until the end of life.

In less severe cases of embolism, at the first stage it is enough heparin treatment, without thrombolytic drugs, the use of which is associated with a risk of serious complications (intracranial bleeding in 3%).

In addition, invasive methods are sometimes used to treat pulmonary embolism: embolectomy or installation of a filter in the main inferior vein. An embolectomy involves physically removing blood clots from the pulmonary arteries. This procedure is used only in cases where the pulmonary embolism is very severe and there are contraindications to classical therapy, for example, bleeding from internal organs or previous history of bleeding.

Embolectomy is also performed in cases where thrombolytic therapy has proven ineffective. To be able to perform an embolectomy, the use of cardiopulmonary bypass systems is required. But, since this procedure is burdensome for the body, it is decided upon only in extreme cases.

The filter is inserted into the main inferior vein to block the passage of embolic material from the lower extremities to the heart and lungs. Used in patients with confirmed deep vein thrombosis of the lower extremities, in whom thrombolysis cannot be used because there are critical contraindications or thrombolytic therapy is ineffective.

Complication of pulmonary embolism - pulmonary infarction

When it comes to blockage of the branches of the pulmonary artery, pulmonary infarction can occur. This complication affects 10-15% of patients with pulmonary embolism. Pulmonary infarction occurs when small cardiopulmonary vessels (with a diameter of less than 3 mm) are blocked and in the presence of associated additional factors (as discussed below). A pulmonary infarction is a focus of necrosis in the lung tissue that occurs due to insufficient oxygen supply to a given “area” - similar to a myocardial infarction.

This is a rare complication of pulmonary embolism because the lungs are vascularized through two systems - pulmonary circulation and branches of the bronchial artery. When one of the oxygen delivery systems fails, the other at least partially compensates for the decrease in oxygen delivery. In practice, pulmonary infarction usually occurs in older people who also suffer from left ventricular failure, as well as in those whose lungs already suffer from some kind of disease: cancer, atelectasis, pneumothorax, inflammation.

If a pulmonary embolism is complicated by a pulmonary infarction, symptoms of the latter appear within a few hours. This is severe chest pain (especially during inhalation) and cough, often with bloody discharge. Sometimes fever occurs. The area of ​​necrosis is usually located on the periphery of the lungs, mainly within the lower left or right lobe. In more than half of the cases there is more than one.

Treatment of pulmonary infarction consists primarily of eliminating pulmonary embolism. It is necessary to supply oxygen and prevent infection of dead tissue.

It is worth remembering about other possible causes of pulmonary infarction, such as:

• inflammatory vascular diseases;
• infections within blood vessels;
• a blockage caused by cancer cells that may have entered the blood vessels.

Symptoms of a pulmonary infarction may resemble a heart attack. In any case, they should not be underestimated.

Modern medicine has a wide range of tools for diagnosing and treating acute venous thrombosis and pulmonary embolism. Nevertheless, it should be remembered that the main way to combat this most dangerous complication is prevention, carried out jointly by doctors and patients. The fight against excess weight, uncontrolled use of hormonal drugs, smoking, physical inactivity, conscious and active implementation of medical recommendations can significantly reduce the frequency of tragedies and misfortunes caused by this disease.

Pulmonary thromboembolism is one of the most serious and dangerous diseases to which humanity annually pays tribute with the death of many, many thousands of patients. In the United States of America, three patients died last year from AIDS, which American society has poured enormous resources into fighting. At the same time, in this country, according to the American Medical Association, up to 650,000 cases of pulmonary embolism are observed annually. About a third of them end in the death of the patient.

Pulmonary embolism: what it is, prevention and treatment

• What is pulmonary embolism?

In the Russian Federation, according to experts, about 100,000 people die annually from pulmonary embolism. Thus, this disease claims more lives than car accidents, regional conflicts and criminal incidents combined.

What is pulmonary embolism?

Let us recall some information from the school anatomy course. The human heart consists of a right and left section, each of which includes an atrium and a ventricle, separated by valves that allow blood to flow in only one direction. These departments do not communicate directly with each other. Venous blood (with a low oxygen content) enters the right atrium through the superior and inferior vena cava. The blood then enters the right ventricle, which contracts and pumps it into the pulmonary trunk. The trunk soon divides into the right and left pulmonary arteries, which carry blood to both lungs.

The arteries, in turn, break up into lobar and segmental branches, which are further divided into arterioles and capillaries. In the lungs, venous blood is cleared of carbon dioxide and, enriched with oxygen, becomes arterial. It enters the left atrium through the pulmonary veins and then into the left ventricle. From there, under high pressure, the blood is pushed into the aorta, then goes through the arteries to all organs. The arteries branch into smaller and smaller ones and eventually become capillaries.

The speed of blood flow and its pressure by this time are significantly reduced. Oxygen and nutrients enter the tissues through the walls of the capillaries from the blood, and carbon dioxide, water and other metabolic products enter the blood. After passing through the network of capillaries, the blood becomes venous. The capillaries merge into venules, then into increasingly larger veins, and eventually the two largest veins - the superior and inferior vena cava - flow into the right atrium. As long as we are alive, this cycle repeats itself over and over again.

Pulmonary embolism is called a disease in which dense blood clots (thrombi), formed in the main veins, break away from the vessel wall, enter the right side of the heart with the blood flow and then into the pulmonary arteries. A thrombus that migrates through the vessels is called an embolus.

As a result of pulmonary embolism(especially massive, which means blockage of at least one of the main pulmonary arteries) the work of the heart, pulmonary blood flow and gas exchange are catastrophically disrupted. In this case, the right ventricle is, as it were, “choked” with blood entering through the vena cava, which it is not able to pump through the pulmonary arterial bed closed by a thrombus. The patient experiences severe suffocation, chest pain, and severe weakness. The upper half of the body becomes blue, blood pressure drops, and a rapid death is very likely.

Fortunately, large (massive) thromboemboli do not always reach the lungs. If their size is small, they disrupt blood flow only in the lobar or segmental pulmonary arteries, which is manifested by symptoms of pulmonary infarction (chest pain, aggravated by breathing, cough, hemoptysis, increased body temperature). Sometimes such “minor” embolism may not manifest itself at all until repeated episodes lead to more severe changes in pulmonary blood flow.

Pulmonary embolism is not an independent disease that suddenly develops in the midst of complete health. It is necessarily preceded by the occurrence of venous thrombosis. Blood clots formed in the inferior vena cava basin are especially dangerous: in the deep veins of the pelvis and lower extremities. The fight against pulmonary embolism should begin at the distant frontiers - with treatment, or better yet, with the prevention of venous thrombosis.

Why do blood clots occur in veins?

The causes of intravascular thrombus formation were formulated back in the middle of the 18th century by the outstanding German pathologist Rudolf Virchow, who proposed the term “embolism”. A thrombus is formed as a result of damage to the vascular wall, slowing blood flow and changes in the composition of the blood itself. Sometimes one reason is enough. If all three are present, thrombus formation is inevitable.

Veins are quite delicate and easily wounded anatomical formations. Their walls are much thinner than those of arteries of the same diameter. Blood pressure in the veins is much lower, so the middle (muscular) layer is less developed. Veins are less resistant to external compression and injury; they are easily involved in the inflammatory process even without the participation of microorganisms. In addition, the veins have valves, damage to which and stagnation of blood in the area where they are located contribute to the formation of blood clots.

Much more complicated than in arteries, the movement of blood through veins is also carried out. Blood is pushed through the arteries by powerful contractions of the left ventricle. From the legs and lower half of the torso, blood returns to the heart from the bottom up, against gravity.

What contributes to this difficult process? First of all, muscle work. Their regular contractions during walking and exercise cause compression of the deep veins. The valves present in the veins allow blood to flow only to the heart. This mechanism, called the muscular-venous pump, essentially acts as a second peripheral venous heart. It is very important for the normal functioning of blood circulation. The negative pressure that occurs in the chest cavity during respiratory movements of the diaphragm and chest walls, as well as the transmitting pulsation of the arteries lying next to the veins, help return blood to the heart.

Maintaining blood in a liquid state is ensured by the simultaneous operation of a huge number of complex biochemical mechanisms. They maintain a precise balance between the coagulation and anticoagulation systems of the blood. There are a large number of typical situations, well known to doctors, in which venous blood flow is simultaneously disrupted and the coagulation system is activated.

For example, during any surgical operation, a large amount of tissue thromboplastin, a substance that stimulates blood clotting, enters the bloodstream from the tissues. The more severe and extensive the operation, the greater the release of this substance. The same thing happens with any injury.

This mechanism was formed in ancient times, and without it humanity, as a biological species, simply would not have survived. Otherwise, any injury to our distant ancestors, and to us, would have ended in death from bleeding. The body, as an integral system, is indifferent to what caused the wound - the claws of a saber-toothed tiger or a surgeon's scalpel. In any case, the blood clotting potential is rapidly activated. But this protective mechanism can often play a negative role, since it creates the preconditions for the formation of blood clots in the venous system in operated patients.

On the first day after surgery, it is difficult for the patient to get up, move and walk. This means that the work of the muscular-venous pump is turned off and venous blood flow slows down. In case of injuries, in addition, it is necessary to apply plaster casts, skeletal traction, and connect bone fragments with metal pins, which sharply limits the patient’s physical activity and contributes to the occurrence of thrombosis. Its incidence after surgical operations on the abdominal organs can reach 25-40%. With hip fractures, knee and hip replacements, thrombosis in the deep veins of the legs develops in 60-70% of patients.

The most serious problem is venous thromboembolic complications during pregnancy. Even in economically developed countries, such as the USA, France, Japan, Switzerland, where they have learned to successfully deal with many of the complications, pulmonary embolism has taken one of the first places in the structure of maternal mortality.

The fact is that a woman’s body itself prepares in advance for childbirth, and therefore for blood loss. Already from the early stages of pregnancy, the blood coagulation system is activated. The tone of the veins decreases due to the general softening of the connective tissue. The inferior vena cava and iliac veins are compressed by the growing uterus. Consequently, all components of Virchow's triad are present, and thrombosis easily occurs. Even obstetricians and gynecologists do not always notice this danger, often regarding swelling of the lower extremities (one of the main signs of thrombosis) as a complication of pregnancy associated with impaired renal function.

Acute venous thrombosis may complicate the use of hormonal contraceptives. These drugs seem to deceive the woman’s body, “convincing” it that pregnancy has already occurred, and hemostasis naturally reacts by activating the coagulation system. Although pharmacologists try to reduce the hormone content, primarily estrogens, in these drugs, the incidence of venous thrombosis (and therefore the possibility of pulmonary embolism) in women taking hormonal contraceptives is at least 3-4 times higher than in those taking hormonal contraceptives. who doesn't accept them. The risk of blood clots is especially high in women who smoke, since nicotine releases thromboxane, a powerful blood clotting factor. Excess weight also actively promotes thrombus formation.

Venous thrombosis is a common complication of neoplasms, both malignant and benign. Patients with tumors usually have increased blood clotting. This is apparently due to the fact that the patient’s body prepares in advance for the future disintegration of the growing tumor. Often, venous thrombosis acts as the first clinical sign of the onset of a cancer process.

Even a long flight in a cramped airplane seat, with legs bent at the knees, and forced inactivity, can provoke vein thrombosis (“economy class syndrome”).

Thus, any surgical intervention, any injury, pregnancy, childbirth, any disease associated with the patient’s immobility, circulatory failure, can be complicated by venous thrombosis and pulmonary embolism. This is precisely what explains such a high incidence of venous thromboembolic complications, even in countries with well-developed medicine.

The insidiousness of venous thrombosis also lies in the fact that its clinical manifestations do not cause the patient a feeling of great distress. Swelling of the leg, pain, usually of a moderate nature, and slight cyanosis of the limb do not frighten patients, and sometimes they do not even consider it necessary to see a doctor. In this case, without any warning, a blood clot can break away from the vein wall in a few seconds, turn into an embolus and cause severe thromboembolism of the pulmonary arteries with an unpredictable outcome. That is why pulmonary embolism is perceived as a “bolt from the blue” not only by patients, but also by doctors.

Fortunately, not every venous thrombosis is complicated by thromboembolism, although their number is very high. So-called floating blood clots are dangerous. This is a variant of thrombosis when the top of the thrombus is washed with blood on three sides and is fixed to the wall of the vein only at one point at the base. The thrombus sways in the bloodstream with any sudden movement, coughing, straining, easily breaks off and “flies” into the pulmonary artery. It is impossible to find out which thrombus threatens pulmonary embolism and which does not during a routine examination of the patient. This requires special instrumental research methods.

Prevention and treatment of thrombosis

So, the fight against deadly thromboembolism of the pulmonary arteries is primarily a fight against acute venous thrombosis. Of course, it is much more effective to prevent thrombosis than to treat it. That is why the problem of preventing venous thromboembolic complications is now attracting the attention of doctors of various specialties, pharmacologists, pathophysiologists and biochemists. This is why surgeons, oncologists, gynecologists, physical therapy doctors so persistently try to get their patients out of bed the next day after surgery, or even on the same day, in order to take a few steps around the ward (often hearing accusations from their patients of all the deadly sins ). In this case, the common phrase “movement is life” comes to mind very opportunely. That is why low-traumatic endoscopic operations are of such interest among surgeons, and active methods of treating injuries among traumatologists.

Of the pharmacological agents that prevent thrombosis, the so-called low molecular weight heparins, administered in prophylactic doses before surgery and in the first days after it, have proven themselves to be the best. The integrated use of physical and pharmacological measures can reduce the number of pulmonary embolisms by 5-7 times, although, unfortunately, it does not completely eliminate them.

If thrombosis of the main veins has already developed, then doctors direct all efforts primarily to preventing pulmonary embolism. Previous attempts to remove the thrombus completely turned out to be futile, since against the background of altered hemostasis, a new thrombus appears on the inflamed vein wall, more friable and even more dangerous. Venous thrombosis does not threaten the vitality of the leg, since the arteries that pass through the blood flow regularly bring oxygen and nutrients. Venous gangrene is a very rare complication; it develops if blood clots close absolutely all veins, both deep and subcutaneous. Therefore, simultaneously with antithrombotic therapy aimed at preventing the growth and spread of a blood clot, the patient is examined to identify floating, embolic forms of venous thrombosis.

For a long time, only phlebography was used for this, that is, x-ray examination of the main veins using a contrast agent. Currently, most patients can be diagnosed using ultrasound techniques. First of all, this is an ultrasound angioscanning, which does not require venous puncture, the introduction of a toxic contrast agent and, which is very important - especially when examining pregnant women, is not associated with irradiation of the patient. At the same time, the information content of the study is not inferior to phlebography.

In cases where a floating thrombus is detected during examination, the most important thing is to prevent a possible pulmonary embolism. In specialized clinics, so-called vena cava filters are used for this purpose.

If for some reason it is not possible to install or, as surgeons say, implant a vena cava filter, you can perform plication of the inferior vena cava. This is an operation in which the lumen of the vena cava is sutured with U-shaped mechanical sutures, as a result of which one wide lumen of the vein turns into several narrow channels that allow blood to pass through and do not allow large blood clots to pass through.

But the most dangerous, often catastrophic course of the situation occurs when a pulmonary embolism has already occurred. Thromboemboli are usually large in size, and in most patients they close the pulmonary trunk or main pulmonary arteries.

For quite a long time, the only possible attempt to help these people was to perform a complex and traumatic operation - pulmonary embolectomy. In this case, the sternum was dissected, the pulmonary trunk was opened and emboli were removed from its lumen. The best results were achieved when artificial blood circulation was used during this operation, a complex and expensive procedure that did not allow such interventions to be widely performed.

Now thrombolytic therapy is increasingly used for pulmonary embolism, which allows saving previously doomed patients. A group of drugs has been created that can dissolve fibrin, the main binding component of blood clots. A catheter is inserted into the pulmonary trunk through the subclavian vein, through which a thrombolytic agent enters the thrombus.

Thrombolytics are highly effective drugs, but their use is possible only in specialized departments and is administered by highly qualified specialists with the necessary knowledge and experience.

Modern medicine has a wide range of tools for diagnosing and treating acute venous thrombosis and pulmonary embolism. Nevertheless, it should be remembered that the main way to combat this most dangerous complication is prevention, carried out jointly by doctors and patients. The fight against excess weight, uncontrolled use of hormonal drugs, smoking, physical inactivity, conscious and active implementation of medical recommendations can significantly reduce the frequency of tragedies and misfortunes caused by this disease. published.

Professor A. Kiriyenko, Associate Professor V. Andriyashkin (Russian State Medical University)

P.S. And remember, just by changing your consciousness, we are changing the world together! © econet

Pulmonary embolism (PE) - causes, diagnosis, treatment

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The site provides reference information for informational purposes only. Diagnosis and treatment of diseases must be carried out under the supervision of a specialist. All drugs have contraindications. Consultation with a specialist is required!

The concept of pulmonary embolism

Incidence and mortality from pulmonary embolism

Currently, cases of pulmonary embolism have become more frequent in the following cases:

• against the background of severe pathology;
• as a result of complex surgical intervention;
• after an injury.

Causes of pulmonary embolism

The most common disease leading to pulmonary embolism is deep vein thrombosis of the legs. Thrombosis of the leg veins is quite common, and the lack of adequate treatment and correct diagnosis of this pathological condition significantly increases the risk of developing pulmonary embolism. Thus, PE develops in 40-50% of patients with thrombosis of the femoral veins. Any surgical intervention can also be complicated by the development of pulmonary embolism.

Risk factors for developing pulmonary embolism

• age over 50 years;
• low physical activity;
• surgical interventions;
• oncological diseases;
• heart failure, including heart attack;
• childbirth that occurred with complications;
• traumatic injuries;
• taking hormonal contraceptives;
• excess body weight;
• genetic pathologies (deficiency of antithrombin III, proteins C and S, etc.).

Classification of pulmonary embolism

• site of blockage of the vessel;
• size of the blocked vessel;
• the volume of pulmonary arteries whose blood supply has ceased as a result of embolism;
• the course of the pathological condition;
• the most pronounced symptoms.

It is common to divide PE, according to the level of localization in a simplified form, into obstruction of small or large branches of the pulmonary artery.
Also, depending on the location of the thrombus, the affected sides are distinguished:

• right;
• left;
• at both sides.

Severity of pulmonary embolism

The severity of pulmonary embolism also depends on the extent of disruption of normal blood flow (hemodynamics).
The following indicators are used to reflect the severity of blood flow disorders:

• right ventricular pressure;
• pulmonary artery pressure.

The degree of disturbance of the blood supply to the lungs during pulmonary embolism
arteries

Symptoms of various types of pulmonary embolism

Signs common to all types of pulmonary embolism (mandatory):

• shortness of breath that develops suddenly, for no apparent reason;
• increase in the number of heartbeats more than 100 per minute;
• pale skin with a gray tint;
• pain localized in various parts of the chest;
• disturbance of intestinal motility;
• irritation of the peritoneum (tense abdominal wall, pain when palpating the abdomen);
• sudden blood filling of the veins of the neck and solar plexus with bulging, pulsation of the aorta;
• heart murmur;
• severely low blood pressure.

The following symptoms (optional) may develop:

• hemoptysis;
• fever;
• chest pain;
• fluid in the chest cavity;
• convulsive activity.

Characteristics of symptoms of pulmonary embolism

Pain sensations are characterized by significant polymorphism and depend on the severity of thromboembolism, the volume of affected vessels and the degree of general pathological disorders in the body. For example, blockage of the pulmonary artery trunk with pulmonary embolism will lead to the development of chest pain, which is acute, tearing in nature. This manifestation of pain is determined by compression of the nerves in the wall of the blocked vessel. Another variant of pain due to pulmonary embolism is similar to angina pectoris, when compressive, diffuse pain develops in the heart area, which can radiate to the arm, shoulder blade, etc. When a complication of pulmonary embolism develops in the form of a pulmonary infarction, the pain is localized throughout the chest, and intensifies with movements (sneezing, coughing, deep breathing). Less commonly, pain from thromboembolism is localized on the right under the ribs, in the liver area.

Circulatory failure that develops with thromboembolism can provoke the development of painful hiccups, intestinal paresis, tension in the anterior abdominal wall, as well as bulging of large superficial veins of the systemic circulation (neck, legs, etc.). The skin becomes pale in color, and a gray or ashy tint may develop; blue lips appear less frequently (mainly with massive pulmonary embolism).

In some cases, you can listen to a heart murmur in systole, as well as identify galloping arrhythmia. With the development of pulmonary infarction, as a complication of pulmonary embolism, hemoptysis may be observed in approximately 1/3 - 1/2 of patients, combined with severe pain in the chest and high fever. The temperature lasts from several days to one and a half weeks.

Severe pulmonary embolism (massive) is accompanied by cerebrovascular accidents with symptoms of central origin - fainting, dizziness, convulsions, hiccups or coma.

In some cases, symptoms of acute renal failure are associated with disorders caused by pulmonary embolism.

The symptoms described above are not specific to pulmonary embolism, therefore, to make a correct diagnosis, it is important to collect the entire medical history, paying special attention to the presence of pathologies leading to vascular thrombosis. However, pulmonary embolism is necessarily accompanied by the development of shortness of breath, an increase in heart rate (tachycardia), increased breathing, and pain in the chest area. If these four symptoms are absent, then the person does not have pulmonary embolism. All other symptoms must be considered together, taking into account the presence of deep vein thrombosis or a previous heart attack, which should put the doctor and close relatives of the patient on alert regarding the high risk of developing pulmonary embolism.

Complications of pulmonary embolism

The main complications of pulmonary embolism are as follows:

• pulmonary infarction;
• paradoxical embolism of large vessels;
• chronic increase in pressure in the blood vessels of the lungs.

Pulmonary embolism causes serious pathological changes, leading to disability and serious disturbances in the functioning of organs and systems.

The main pathologies that develop as a result of pulmonary embolism:

• pulmonary infarction;
• empyema;
• pneumothorax;
• acute renal failure.

Pulmonary infarction is complicated by pulmonary embolism due to a combination of several factors:

• blockage of a vessel by a thrombus;
• decrease in blood supply to the lung area due to a decrease in that in the bronchial tree;
• disruption of the normal passage of air through the bronchi;
• the presence of cardiovascular pathology (heart failure, mitral valve stenosis);
• presence of chronic obstructive pulmonary disease (COPD).

• sharp chest pain;
• hemoptysis;
• dyspnea;
• a crunching sound when breathing (crepitus);
• moist wheezing over the affected area of ​​the lung;
• fever.

Pleurisy (inflammation of the pleura) is a complication of pulmonary infarction, which is caused by the leakage of pathological fluid from the affected area of ​​the organ. The amount of sweated fluid is usually small, but sufficient to involve the pleura in the inflammatory process.

In the lung in the area where the infarction develops, the affected tissue undergoes decay with the formation of an abscess (abscess), which evolves into a large cavity (cavity) or pleural empyema. Such an abscess can open, and its contents, consisting of tissue decay products, enter the pleural cavity or the lumen of the bronchus, through which it is removed to the outside. If pulmonary embolism was preceded by the presence of a chronic infection of the bronchi or lungs, the area of ​​damage due to the infarction will be larger.

Pneumothorax, pleural empyema, or abscess develop rarely after pulmonary infarction caused by PE.

Pathogenesis of pulmonary embolism

Blockage of the vessels of the lung leads to the development of various respiratory disorders and circulatory pathologies. The cessation of blood supply to an area of ​​the lung occurs due to blockage of the vessel. As a result of blockage by a blood clot, blood cannot pass further than this section of the vessel. Therefore, the entire lung that is left without blood supply forms the so-called “dead space”. The entire area of ​​the “dead space” of the lung collapses, and the lumen of the corresponding bronchi narrows greatly. Forced dysfunction with disruption of the normal nutrition of the respiratory organs is aggravated by a decrease in the synthesis of a special substance - surfactant, which maintains the alveoli of the lung in a non-collapsed state. Impaired ventilation, nutrition, and a small amount of surfactant - all these factors are key in the development of pulmonary atelectasis, which can fully develop within 1-2 days after pulmonary embolism.

Blockage of the pulmonary artery also significantly reduces the area of ​​normal, actively functioning vessels. Moreover, small blood clots clog small vessels, and large ones clog large branches of the pulmonary artery. This phenomenon leads to an increase in working pressure in the pulmonary circle, as well as to the development of heart failure of the cor pulmonale type.

Often, the immediate consequences of vascular blockage are accompanied by the effects of reflex and neurohumoral regulatory mechanisms. The whole complex of factors together leads to the development of severe cardiovascular disorders that do not correspond to the volume of the affected vessels. These reflex and humoral mechanisms of self-regulation include, first of all, a sharp constriction of blood vessels under the influence of biologically active substances (serotonin, thromboxane, histamine).

Thrombosis in the veins of the legs develops based on the presence of three main factors, combined into a complex called Virchow's triad.

Virchow's Triad includes:

• area of ​​damaged inner wall of the vessel;
• decreased blood flow speed in the veins;
• hypercoagulation syndrome.

Sufficiently “fresh” blood clots in the pulmonary vessels can be dissolved, and with little effort. Such dissolution of a blood clot (lysis), as a rule, begins from the moment it is fixed in a vessel with a blockage of the latter, and this process takes place within one and a half to two weeks. As the blood clot dissolves and normal blood supply to the lung area is restored, the organ is restored. That is, a complete recovery is possible with restoration of the functions of the respiratory organ after suffering a pulmonary embolism.

Recurrent pulmonary embolism is a blockage of small branches of the pulmonary artery.

Course, causes, symptoms, diagnosis, complications Unfortunately, pulmonary embolism can recur several times throughout life. Such repeated episodes of this pathological condition are called recurrent pulmonary embolism. 10-30% of patients who have already suffered from this pathology are susceptible to recurrent pulmonary embolism. Typically, one person can experience a varying number of episodes of pulmonary embolism, ranging from 2 to 20. A large number of episodes of pulmonary embolism experienced are usually represented by blockage of the small branches of the pulmonary artery. Thus, the recurrent form of pulmonary embolism is morphologically a blockage of the small branches of the pulmonary artery. Such multiple episodes of occlusion of small vessels usually lead subsequently to embolization of large branches of the pulmonary artery, which forms a massive pulmonary embolism.

The development of recurrent pulmonary embolism is facilitated by the presence of chronic diseases of the cardiovascular and respiratory systems, as well as oncological pathologies and surgical interventions on the abdominal organs. Recurrent pulmonary embolism usually does not have clear clinical signs, which causes its mild course. Therefore, this condition is rarely correctly diagnosed, since in most cases unexpressed signs are mistaken for symptoms of other diseases. Thus, recurrent pulmonary embolism is difficult to diagnose.

Most often, recurrent pulmonary embolism is disguised as a number of other diseases. Typically this pathology is expressed in the following conditions:

• recurrent pneumonia occurring for an unknown reason;
• pleurisy that lasts for several days;
• fainting conditions;
• cardiovascular collapse;
• attacks of suffocation;
• increased heart rate;
• labored breathing;
• elevated temperature that is not relieved by antibacterial drugs;
• heart failure in the absence of chronic heart or lung diseases.

• pneumosclerosis (replacement of lung tissue with connective tissue);
• emphysema;
• increased pressure in the pulmonary circulation (pulmonary hypertension);
• heart failure.

Diagnosis of pulmonary embolism

• mandatory, which are prescribed to all patients with a presumable diagnosis of pulmonary embolism to confirm it (ECG, X-ray, echocardiography, lung scintigraphy, ultrasound of leg veins);
• additional ones, which are carried out if necessary (angiopulmonography, ileocavagraphy, pressure in the ventricles, atria and pulmonary artery).

Among the laboratory parameters, with pulmonary embolism the values ​​of the following change:

• increase in bilirubin concentration;
• an increase in the total number of white blood cells (leukocytosis);
• increased erythrocyte sedimentation rate (ESR);
• an increase in the concentration of fibrinogen degradation products in the blood plasma (mainly D-dimers).

Thus, X-ray changes appear quite rarely and are not strictly specific, that is, characteristic of pulmonary embolism. Therefore, X-ray in the diagnosis of pulmonary embolism does not allow making the correct diagnosis, but can help distinguish the disease from other pathologies that have the same symptoms (for example, lobar pneumonia, pneumothorax, pleurisy, pericarditis, aortic aneurysm).

An informative method for diagnosing pulmonary embolism is an electrocardiogram, and changes in it reflect the severity of the disease. The combination of a certain ECG pattern with a medical history allows you to diagnose PE with high accuracy.

Echocardiography will help determine the exact location in the heart, shape, size and volume of the blood clot that caused PE.

The lung perfusion scintigraphy method reveals a large array of diagnostic criteria, so this study can be used as a screening test for the detection of pulmonary embolism. Scintigraphy allows you to obtain a “picture” of the pulmonary vessels, which has clearly demarcated areas of circulatory disturbance, but it is impossible to determine the exact location of the artery blockage. Unfortunately, scintigraphy has a relatively high diagnostic value only for confirming pulmonary embolism caused by obstruction of large branches of the pulmonary artery. PE associated with obstruction of small branches of the pulmonary artery is not detected by scintigraphy.

To diagnose PE with higher accuracy, it is necessary to compare data from several examination methods, for example, the results of scintigraphy and x-rays, as well as take into account anamnestic data indicating the presence or absence of thrombotic diseases.

The most reliable, specific and sensitive method for diagnosing pulmonary embolism is angiography. Visually, an angiogram reveals an empty vessel, which is expressed in a sharp break in the course of the artery.

Urgent care for pulmonary embolism

The package of urgent assistance measures includes the following measures:

• bed rest;
• installation of a catheter in the central vein, through which medications are administered and venous pressure is measured;
• administration of heparin up to 10,000 units intravenously;
• oxygen mask or administration of oxygen through a catheter in the nose;
• constant injection of dopamine, rheopolyglucin and antibiotics into the vein if necessary.

Treatment of pulmonary embolism

• heparin;
• fraxiparine;
• streptokinase;
• urokinase;
• tissue plasminogen activator.

Streptokinase and urokinase are administered intravenously overnight, on average once a month. Tissue plasminogen activator is also used intravenously, with a single dose administered over several hours.

Thrombolytic therapy cannot be carried out after surgery, or in the presence of diseases that are potentially dangerous for bleeding (for example, peptic ulcer). In general, it must be remembered that thrombolytic drugs increase the risk of bleeding.

Surgical treatment of pulmonary embolism
Surgical treatment of pulmonary embolism is performed when more than half of the lungs are affected. The treatment is as follows: using a special technique, the clot is removed from the vessel to remove the obstacle to the blood flow. Complex surgical intervention is indicated only for blockage of large branches or the trunk of the pulmonary artery, since it is necessary to restore blood flow throughout almost the entire area of ​​the lungs.

Prevention of pulmonary embolism

Prevention of pulmonary embolism is carried out in people at high risk of developing the pathology.

It is advisable to prevent pulmonary embolism in the following categories of people:

• over 40 years old;
• suffered a heart attack or stroke;
• excess body weight;
• surgeries on the abdominal, pelvic, leg and chest organs;
• a past episode of deep vein thrombosis or pulmonary embolism.

• Ultrasound of leg veins;
• tight leg bandaging;
• compression of the leg veins with special cuffs;
• regular injection of heparin under the skin, fraxiparin or rheopolyglucin into a vein;
• ligation of large veins of the legs;
• implantation of special vena cava filters of various modifications (for example, Mobin-Uddin, Greenfield, “Gunther’s tulip”, “hourglass”, etc.).

Thus, pulmonary embolism is a very serious pathological condition that can result in death or disability. Due to the seriousness of the disease, it is necessary, if there is the slightest suspicion of pulmonary embolism, to consult a doctor or call an ambulance in a serious condition. If there has been an episode of pulmonary embolism, or there are risk factors, alertness regarding this pathology should be maximum. Always keep in mind that it is easier to prevent a disease than to treat it, so do not neglect preventive measures.

Pulmonary embolism is a condition characterized by blockage of the pulmonary artery or its branches by blood clots. In terms of its prevalence, the disease ranks third after coronary heart disease and stroke.

Peculiarities

The development of embolism is caused by blockage of the pulmonary artery due to the separation and movement of a blood clot from the site of its initial formation. The consequences depend on the size and number of detached emboli and the general condition of the circulatory system. Blockage of blood flow by large clots leads to disruption of gas exchange and the development of hypoxia. The pressure in the pulmonary arteries increases and the load on the right ventricle of the heart increases.

In addition to blood clots, blood vessels can clog:

• air bubbles;
• drops of fat (formed by bone fractures, intravenous administration of oily solutions);
• tumor particles;
• foreign bodies.

The most common source of blood clots is the veins of the lower extremities., less often - the hands and the right side of the heart.

The prevalence of the pathology is quite high and amounts to 1 case per thousand people. Men are at higher risk, especially in old age.

Causes

Cardiologists name the main causes of the disease:

• impaired blood flow (varicose veins, cysts, tumors, excessive blood viscosity) - stagnation of blood in the extremities significantly increases the likelihood of blood clots forming and breaking off;
• increased blood clotting;
• inflammation of the venous walls.

Additional risk factors are:

• the presence of cardiovascular diseases - myocardial infarction, arrhythmia, mitral disease, heart failure;
• low physical activity;
• prolonged bed rest;
• postoperative period;
• pregnancy and childbirth;
• smoking;
• taking birth control pills;
• oncological diseases - cancer of the pancreas, stomach, lungs;
• installation of a pacemaker.

Also at increased risk are people suffering from hypertension and a number of diseases of the gastrointestinal tract (peptic ulcer, colitis), undergoing treatment with hormones and chemotherapy.

Classification

The following types of embolism are distinguished:

• massive– manifests itself in damage to more than half the volume of the vascular bed. Accompanied by a decrease in blood pressure and shock;
• submassive– from 30 to 50% of the volume is affected. There is blockage of several segmental arteries. The patient exhibits symptoms of heart failure;
• non-massive– pathological phenomena involve less than 30% of the vascular bed. Manifestations of the disease are minimal.

The development of the clinical picture allows us to describe the following forms of the disease:

• lightning fast– develops when a blood clot blocks the main trunk of an artery or both of its branches. The condition is characterized by a rapid drop in pressure and the development of respiratory failure. Death occurs within minutes;
• acute– occurs in case of blockage of the main, lobar or segmental branches by blood clots. Within 3–5 days, patients develop respiratory and heart failure, and a pulmonary infarction occurs;
• subacute– diagnosed with obstruction of large and medium-sized vessels, lasts several weeks, often recurs;
• chronic– manifests itself in repeated blockages of blood vessels by blood clots and the occurrence of recurrent pleurisy and heart attacks. Occurs mainly in the postoperative period, as well as in patients with cancer and cardiac diseases.

Symptoms of pulmonary embolism

Experts do not identify specific manifestations unique to this disease. The main symptoms include:

• chest pain that increases with inhalation and movement;
• cough with possible discharge of bloody sputum;
• decreased blood pressure;
• temperature increase;
• formation of cold sweat;
• pale skin;
• loss of consciousness.

With the development of embolism in the small branches of the pulmonary arteries, the patient may develop nonspecific symptoms (rare cough, slight increase in temperature), or any symptoms may be absent at all.

The severity of symptoms does not always thoroughly reflect the true situation of pathology development. Thus, when a small vessel is blocked, a person may experience unbearable pain, while when the pulmonary artery is damaged, only slight shortness of breath may occur.

The manifestations of pulmonary embolism largely coincide with the symptoms of pneumonia, myocardial infarction, and heart failure. This is the main danger of the condition, since in the absence of timely medical care, the disease can be fatal.

Diagnostics

Making a diagnosis is fraught with certain difficulties, since the disease does not have specific symptoms, and standard studies are carried out mainly to exclude other pathologies.

If the development of embolism is suspected, the following examinations are carried out:

• electrocardiography– allows you to exclude myocardial infarction and confirm the fact of embolism using indirect signs;
• radiography– reveals the presence of fractures, pneumonia, pulmonary edema, pneumothorax.

Currently the most informative are:

• echocardiography– allows you to detect disturbances in the functioning of the right ventricle, identify blood clots in the heart cavity;
• CT scan– allows you to identify emboli of any size in the pulmonary artery and their location;
• magnetic resonance tomography is used to detect blood clots in the branches of arteries;
• angiopulmonography– is based on the injection of a special colored solution into the pulmonary artery, which allows you to thoroughly determine the position and size of the clot;
• level determinationd-dimer, an increase in which indicates recent thrombus formation;
• ultrasonography(Doppler and compression) allows you to detect the presence of blood clots in the lower extremities.

Treatment

A patient diagnosed with pulmonary embolism should be immediately admitted to the emergency room or intensive care unit.

In case of cardiac arrest, cardiopulmonary resuscitation measures are performed - defibrillation, chest compressions. With the development of oxygen starvation, oxygen therapy is carried out using masks and nasal catheters, and in difficult situations - artificial ventilation. With a significant decrease in blood pressure, intravenous administration of adrenaline, dopamine, and saline solution is indicated.

Further treatment involves anticoagulant therapy. To suppress thrombin production, a single dose of heparin is prescribed in a dosage of 5,000 to 10,000 units intravenously, followed by a maintenance drip (up to 1,500 units per hour). The duration of the therapeutic course is 5–10 days.

As an alternative, subcutaneous injections of low molecular weight heparin - enoxaparin, dalteparin or fondaparinux - are offered. They are highly effective and safer. The dosage is selected individually, taking into account the patient’s body weight and his individual characteristics.

On the second day after the start of treatment, the patient is prescribed warfarin, which suppresses the synthesis of proteins necessary for coagulation in the blood. The drug is taken in tablet form once a day, 5 or 7.5 mg. The duration of warfarin therapy is at least 3 months.

Thrombolytic therapy is performed to restore blood flow and dissolve clots. The most effective drugs are:

• streptokinase– quickly removes newly formed blood clots. It is administered intravenously over 2 hours at a dosage of 1,500,000 IU or in 2 stages - 250,000 IU for 30 minutes, and then 100,000 IU/hour during the day;
• urokinase– activates the clot-destroying enzyme plasmin. 3 million IU is administered intravenously over 2 hours;
• alterplase– also helps break down blood clots. This drug is hypoallergenic. It is prescribed intravenously in a single dose of 100 mg.

When carrying out thrombolytic therapy, there is a high probability of bleeding, which is recorded in 13% of patients.

An alternative treatment method involves surgical removal of the blood clot. 2 types of operations are performed:

1. embolectomy– removal of the blood clot directly;
2. thromboendarterectomy– removal of part of an artery with an embolus attached to it.

Carrying out these operations is fraught with many difficulties. It is necessary to cool the patient's body to 28°C, completely open the chest, connect the artificial circulation system and then cut out the clot.

If a significant risk of complications is identified or if there are strong contraindications to drug treatment, the installation of vena cava filters, which are special meshes for catching detached blood clots and preventing them from entering directly into the pulmonary artery, is indicated.

Vava filters are inserted through the femoral, subclavian or jugular veins through a puncture in the skin. The operation lasts no more than an hour, complications, as a rule, do not arise. This manipulation can be performed both after the development of pulmonary embolism and as a preventive measure.

Complications

The most serious consequences of pulmonary embolism include:

• pneumonia;
• pleurisy;
• abscess and gangrene of the lung.

Failure to provide timely medical care can lead to death. Currently, with adequate treatment, mortality does not exceed 10%.

Prevention

In order to most likely avoid the occurrence of pulmonary embolism, you should follow several simple rules:

• adhere to the principles of healthy eating;
• during long journeys or flights, when staying in a fixed position for a long time, it is necessary to perform a set of exercises for the lower extremities;
• in the postoperative period, an early resumption of physical activity is recommended;
• if there are risk factors for blood clots, wearing compression tights or stockings is recommended;
• massage and pneumomassage helps improve blood circulation and drainage of lymph from the lower extremities.

Knowing the common symptoms of pulmonary embolism will help differentiate it from other diseases and immediately seek help from specialists who will prescribe appropriate treatment. Compliance with preventive measures will help maintain health and avoid serious complications.

Find out what experts think about pulmonary embolism from the video.

Some facts about pulmonary embolism:

• PE is not an independent disease - it is a complication of venous thrombosis (most often of the lower limb, but in general a fragment of a thrombus can enter the pulmonary artery from any vein).
• PE ranks third in prevalence among all causes of death (second only to stroke and coronary heart disease).
• In the United States, there are approximately 650,000 cases of pulmonary embolism and 350,000 associated deaths each year.
• This pathology ranks 1-2 among all causes of death in older people.
• The prevalence of pulmonary embolism in the world is 1 case per 1000 people per year.
• 70% of patients who died from pulmonary embolism were not diagnosed in time.
• About 32% of patients with pulmonary embolism die.
• 10% of patients die in the first hour after the development of this condition.
• With timely treatment, mortality from pulmonary embolism is greatly reduced - up to 8%.

Features of the structure of the circulatory system

1. Systemic circulation begins with the largest artery in the body - the aorta. It carries arterial, oxygenated blood from the left ventricle of the heart to the organs. Throughout its entire length, the aorta gives off branches, and in the lower part it divides into two iliac arteries, supplying blood to the pelvis and legs. Blood, poor in oxygen and saturated with carbon dioxide (venous blood), is collected from organs into venous vessels, which, gradually connecting, form the superior (collects blood from the upper part of the body) and inferior (collects blood from the lower part of the body) vena cava. They flow into the right atrium.


2. Pulmonary circulation begins from the right ventricle, which receives blood from the right atrium. The pulmonary artery departs from it - it carries venous blood to the lungs. In the pulmonary alveoli, venous blood releases carbon dioxide, is saturated with oxygen and turns into arterial blood. It returns to the left atrium through four pulmonary veins flowing into it. Blood then flows from the atrium into the left ventricle and into the systemic circulation.

   Normally, microthrombi constantly form in the veins, but they quickly collapse. There is a delicate dynamic balance. When it is disrupted, a blood clot begins to grow on the venous wall. Over time, it becomes more loose and mobile. Its fragment comes off and begins to migrate with the bloodstream.

   In pulmonary embolism, the detached fragment of the thrombus first reaches the inferior vena cava of the right atrium, then enters the right ventricle, and from there into the pulmonary artery. Depending on the diameter, the embolus clogs either the artery itself or one of its branches (larger or smaller).

Causes of pulmonary embolism

• stagnation of blood in the veins– the slower it flows, the higher the likelihood of a blood clot forming;
• increased blood clotting;
• inflammation of the venous wall– this also contributes to the formation of blood clots.

But there are many factors, each of which increases the likelihood of this condition:

Violation	Causes
Stagnation of blood in the veins
Prolonged stay in an immobilized state– in this case, the functioning of the cardiovascular system is disrupted, venous stagnation occurs, and the risk of blood clots and pulmonary embolism increases.
Increased blood clotting
Increased blood viscosity, resulting in impaired blood flow and an increased risk of blood clots.
Damage to the vascular wall

What happens in the body during pulmonary embolism?

The right ventricle dilates, and insufficient blood flows into the left. Because of this, blood pressure drops. The likelihood of severe complications is high. The larger the vessel is blocked by the embolus, the more pronounced these disorders are.

With pulmonary embolism, the flow of blood to the lungs is disrupted, so the entire body begins to experience oxygen starvation. The frequency and depth of breathing reflexively increases, and the lumen of the bronchi narrows.

Symptoms of pulmonary embolism

Main symptoms of pulmonary embolism:

• , which intensify during a deep breath;
• , during which sputum with blood may come out (if a hemorrhage has occurred in the lung);
• decreased blood pressure (in severe cases – below 90 and 40 mmHg);
• frequent (100 beats per minute) weak pulse;
• cold clammy sweat;
• pallor, gray skin tone;
• body up to 38°C;
• loss of consciousness;
• bluishness of the skin.

If a patient with pulmonary embolism is not provided with emergency medical care, death may occur.

Symptoms of pulmonary embolism can closely resemble myocardial infarction, pneumonia. In some cases, if thromboembolism has not been identified, chronic thromboembolic pulmonary hypertension develops (increased pressure in the pulmonary artery). It manifests itself in the form of shortness of breath during physical exertion, weakness, and fatigue.

Possible complications of pulmonary embolism:

• cardiac arrest and sudden death;
• pulmonary infarction with subsequent development of an inflammatory process (pneumonia);
• (inflammation of the pleura - a film of connective tissue that covers the lungs and lines the inside of the chest);
• relapse - thromboembolism can occur again, and the risk of death of the patient is also high.

How to determine the likelihood of pulmonary embolism before the examination?

At the moment, special scales have been developed to assess the likelihood of pulmonary embolism in a patient.

Geneva scale (revised):

• 11 points or more– high probability of pulmonary embolism;
• 4-10 points– average probability;
• 3 points or less– low probability.

• 7 points or more– high probability of pulmonary embolism;
• 2-6 points– average probability;
• 0-1 points– low probability.

• 4 points or more- high probability;
• up to 4 points– low probability.

Diagnosis of pulmonary embolism

Study title	Description
Electrocardiography ()	Electrocardiography is a recording of electrical impulses that occur during heart activity in the form of a curve. During an ECG, the following changes can be detected:: increased heart rate; signs of right atrium overload; signs of overload and oxygen starvation of the right ventricle; disruption of the conduction of electrical impulses in the wall of the right ventricle; sometimes atrial fibrillation (atrial fibrillation) is detected. Similar changes can be detected in other diseases, for example, during pneumonia and during a severe attack of bronchial asthma. Sometimes the electrocardiogram of a patient with pulmonary embolism does not show any pathological changes at all.
chest	Signs that can be detected on radiographs:
Computed tomography (CT)	If pulmonary embolism is suspected, spiral CT angiography is performed. The patient is given an intravenous contrast agent and scanned. Using this method, you can accurately determine the location of the thrombus and the affected branch of the pulmonary artery.
Magnetic resonance imaging (MRI)	The study helps visualize the branches of the pulmonary artery and detect a thrombus.
Angiopulmonography	X-ray contrast study, during which a solution of a contrast agent is injected into the pulmonary artery. Pulmonary angiography is considered the “gold standard” in the diagnosis of pulmonary embolism. The photographs show vessels stained with contrast, and one of them breaks off abruptly - there is a blood clot in this place.
(echocardiography)	Signs that can be detected by ultrasound examination of the heart:
Ultrasound examination of veins	Ultrasound scanning of veins helps to identify the vessel that became the source of thromboembolism. If necessary, ultrasound can be supplemented with Doppler ultrasound, which helps assess the intensity of blood flow. If the doctor presses the ultrasound sensor on the vein, but it does not collapse, then this is a sign that there is a blood clot in its lumen.
Scintigraphy	If pulmonary embolism is suspected, ventilation-perfusion scintigraphy is performed. The information content of this method is 90%. It is used in cases where the patient has contraindications to computed tomography. Scintigraphy reveals areas of the lung into which air enters, but at the same time the blood flow to them is impaired.
Determination of d-dimer levels	D-dimer is a substance that is formed during the breakdown of fibrin (a protein that plays a key role in the blood clotting process). An increase in d-dimer levels in the blood indicates recent blood clot formation. Increased levels of d-dimers are detected in 90% of patients with pulmonary embolism. But it is also found in a number of other diseases. Therefore, the results of this study cannot be relied upon alone. If the level of d-dimers in the blood is within normal limits, this often allows us to exclude pulmonary embolism.

Treatment

Drug treatment of pulmonary embolism

Measures taken for massive pulmonary embolism

• Heart failure. Carry out cardiopulmonary resuscitation (indirect cardiac massage, artificial ventilation, defibrillation).
• Hypoxia(low oxygen content in the body) as a result of respiratory failure. Oxygen therapy is carried out - the patient inhales a gas mixture enriched with oxygen (40%-70%). It is given through a mask or through a catheter inserted into the nose.
• Severe respiratory distress and severe hypoxia. Perform artificial ventilation.
• Hypotension (low blood pressure). The patient is injected intravenously through a dropper with various saline solutions. They use drugs that cause a narrowing of the lumen of blood vessels and an increase in blood pressure: dopamine, dobutamine, adrenaline.

Surgical treatment of pulmonary embolism

• massive thromboembolism;
• deterioration of the patient's condition despite conservative treatment;
• thromboembolism of the pulmonary artery itself or its large branches;
• a sharp restriction of blood flow to the lungs, accompanied by a violation of general circulation;
• chronic recurrent pulmonary embolism;
• a sharp decrease in blood pressure;

• Embolectomy– embolus removal. This surgical intervention is performed in most cases of acute pulmonary embolism.
• Thrombendarterectomy– removal of the inner wall of the artery with the plaque attached to it. Used for chronic pulmonary embolism.

Often with PE, as a result of increased pressure in the pulmonary artery, the right ventricle and tricuspid valve are stretched. In this case, the surgeon additionally performs heart surgery—plasty of the tricuspid valve.

Installation of a vena cava filter

Installation of a vena cava filter can be carried out when pulmonary embolism has already occurred, or in advance. This is an endovascular intervention - it does not require making an incision in the skin. The doctor makes a puncture in the skin and inserts a special catheter through the jugular vein (in the neck), subclavian vein (in the collarbone) or the great saphenous vein (in the thigh).

Typically, the intervention is performed under light anesthesia, and the patient does not experience pain or discomfort. Installing a vena cava filter takes about an hour. The surgeon passes a catheter through the veins and, after it reaches the desired location, inserts a mesh into the lumen of the vein, which immediately straightens and secures. After this, the catheter is removed. Sutures are not placed at the intervention site. The patient is prescribed bed rest for 1-2 days.

Prevention

What's the prognosis?

1. 24% of patients with pulmonary embolism die within a year.
2. 30% of patients in whom pulmonary embolism was not detected and not treated in a timely manner die within a year.


3. With repeated thromboembolism, 45% of patients die.
4. The main causes of death in the first two weeks after the occurrence of pulmonary embolism are complications of the cardiovascular system and pneumonia.

What is pulmonary embolism? Pulmonary embolism, in layman's terms, is explained by blockage of an artery or its branches in the lung by an embolus. A substance called an embolus is nothing more than part of a blood clot that can form in the hip and lower extremity vessels. Blockage of the lungs, heart or other organs occurs when the embolus partially or completely ruptures and blocks the lumen of the vessel. The consequences of pulmonary embolism are severe; in 25% of the total number of those affected by this pathology, patients do not survive.

Classification of thromboembolism

Systematization of pulmonary embolism is carried out taking into account many factors. Depending on the manifestations, variations in the course of the disease state, the severity of symptoms of pulmonary embolism and other features, grouping is performed.

PE classification:

Causes of thromboembolism

There are many causes of pulmonary embolism. But all of them, one way or another, stem from several main sources of the pathological condition.

The main causes of pulmonary embolism:

• Increased blood flow viscosity.
• Increased blood clotting.
• Stagnation of blood substance in the veins.
• Systemic inflammatory processes in the venous walls (viral and bacterial infections).
• Damage to the vessel wall (endovascular surgical interventions, venous replacement).

The increase in the viscosity of blood fluid is due to certain processes occurring in the body. Often banal dehydration leads to such sad consequences. Another, more serious health problem is erythrocytosis.

An increase in the coagulability of the blood substance is often explained by an increase in the amount of fibrinogen protein, which is responsible for this process. Blood tumors such as polycythemia greatly increase the level of red blood cells and platelets. Taking certain medications promotes increased blood clotting.

During pregnancy, thrombus formation often increases.

Stagnation of blood flow in the veins is observed in individuals prone to obesity. Diabetes mellitus leads to impaired fat metabolism and the deposition of cholesterol in the form of plaques on the walls of blood vessels. Often the causes of pulmonary embolism lie in heart failure. People who already have varicose veins of the lower extremities are prone to thrombosis. Heavy smokers constantly experience vascular spasms throughout the day; over time, this bad habit leads to severe vascular disorders. Physical inactivity or being forced to be in an immobilized position (postoperative period, disability, after a heart attack and other conditions).

Pathologies leading to pulmonary embolism:

• Thrombosis of the superficial, internal and cava veins.
• Intravascular formation of blood clots (thrombophilia) with pathology of hemostasis.
• Oncological processes and, as a consequence, products of cellular decay.
• Antiphospholipid syndrome, characterized by the production of antibodies to platelet phospholipids. The condition is characterized by increased thrombus formation.
• Diseases of the cardiovascular and respiratory systems, leading to thrombosis and pulmonary embolism.

The causes of pulmonary embolism are explained by age. Before 30 years of age, especially in the absence of specific pathologies, thrombosis and associated consequences, such as pulmonary embolism, are not observed. From which we can conclude that pulmonary embolism is one of the consequences of pathologies of old age.

Symptoms of thromboembolism

Among the signs of pulmonary embolism, there are general ones, characteristic of several pathologies, and specific ones. Thromboembolism of small branches of the pulmonary artery has a weak or completely asymptomatic manifestation; usually, the patient notes a slight increase in body temperature and a persistent cough.

Other symptoms of pulmonary embolism:

• Pain in the sternum, worsening with a deep breath.
• Pale, bluish or gray tint of the skin.
• The appearance of cold perspiration together with sticky sweat.
• Severe decrease in blood pressure.
• Increased heart rate.
• Difficulty breathing, lack of air, shortness of breath.
• Comatose state, fainting, convulsions.
• Sputum with blood during coughing, occurs with hemorrhage.

Pulmonary embolism symptoms can be very similar to myocardial infarction syndrome, a pulmonary pathology. In circumstances where pulmonary embolism has not been identified for any reason. Then there is a possibility that the pathological condition will become chronic with the development of hypertension (increased tension in the pulmonary artery). It is possible to suspect the transition of pulmonary embolism to a chronic form by shortness of breath that appears with any type of pulmonary embolism. Chronic pulmonary embolism is also usually accompanied by constant weakness and severe fatigue.

All of the above symptoms of pulmonary embolism are not specific. But, despite this fact, warning signs similar to pulmonary embolism should not be ignored. It is necessary to urgently call emergency help or consult a doctor at your place of residence. Even if the symptoms of pulmonary embolism are not confirmed, in any case a diagnosis will be needed to find out what was the source of the health deviation.

Thromboembolic disease syndrome can lead to serious complications, including chronic increase in arterial pressure in the lung, pulmonary or renal failure, heart attack, pleurisy or pneumonia, lung abscess and other serious pathologies.

Methods for diagnosing thromboembolism

Diagnosis of pulmonary embolism is divided into mandatory and auxiliary methods. Mandatory diagnostic measures include: ECG, echocardiography, X-ray, scintigraphy, ultrasound of the veins of the lower extremities. PE may include ileocavography, angiopulmonography, measurement of pressure in the atria, ventricles, and pulmonary artery.

Another time-tested method of diagnosis is taking an anamnesis. The information provided by the patient will greatly contribute to drawing up the correct clinical picture. If thromboembolism is clearly suspected, the symptoms expressed by the patient can indicate the degree of development of the pathology, which will determine the measures taken in relation to a specific clinical case of PE. And also, interviewing the person who filed the complaints is useful for obtaining information about previously suffered pathologies with or without surgical intervention.

Especially if the diseases are related to or can affect the development of thromboembolism.

Laboratory diagnosis of pulmonary embolism is effective due to the simplicity, accessibility of the procedure and the speed of obtaining analysis results.

The following indicators indicate thromboembolism syndrome in a blood test:

• Exceeding the total number of leukocytes.
• Increased accumulation of bilirubin.
• Raising the ESR indicator.
• Excessive concentration of the consequences of fibrinogen degradation in the plasma of the blood substance.

Among the mandatory diagnostic methods for pulmonary thromboembolism, the most informative and reliable are the electrocardiogram, echocardiography and antiography. An ECG, especially in combination with a blood test and a study of the collected anamnesis, will make it possible to make the most accurate conclusion, and with clarification of the category of thromboembolism severity. Echocardiography, in turn, will help clarify all the parameters of the blood clot, and in addition its specific location. Antiography is a specific diagnostic method and allows you to obtain a complete overview of the vessels to detect blood clots and identify pulmonary embolism.

Perfusion scintigraphy of the respiratory system is used as a screening test. One thing, scintigraphy allows you to determine the blockage of only the main arteries in the lung; this method is not intended for examining small branches. There is also no way to accurately diagnose thromboembolism using X-rays. This method can only help distinguish PE from other diseases.

Treatment of thromboembolism

First of all, when diagnosing pulmonary thromboembolism, the patient must be provided with emergency care. Urgent measures should be aimed at resuscitation procedures.

The procedure for resuscitation measures for thromboembolism (carried out by medical personnel):

• The patient should be placed in bed or on a flat surface.
• Release tightness from clothing (unbutton the collar, loosen the belt or belt at the waist).
• Provide free access of oxygen to the room.
• Install a central venous catheter, through which the required medications are administered and blood pressure is measured.
• Inject intravenously the direct-acting anticoagulant agent heparin at a dosage of 10,000 units.
• Introduce oxygen through a catheter in the nose or use an oxygen mask.
• Continuous venous infusion of rheopolyglucin (the drug restores blood flow), dopamine (a neurotransmitter hormone), antibiotics to prevent sepsis and other drugs at the discretion of the resuscitation team.

Subsequently, urgent measures were taken to restore pulmonary blood supply, prevent the development of blood poisoning and the formation of hypertension in the lung. It is necessary to move on to the main treatment of thromboembolism, aimed at resolving the blood clot. Pulmonary embolism syndrome is treated by surgically removing the clot. If the patient's condition allows, then thrombolytic therapy can be used. It involves taking a course, and sometimes more than one, of taking special medications, the action of which is aimed at the complete elimination of thrombus formation in the artery of the lung and throughout the body.

Treatment of pulmonary embolism is carried out with the following drugs:

• Clexane or its analogues.
• Novoparin (Heparin).
• Fraxiparine.
• Streptase.
• Plasminogen.

Treatment of pulmonary embolism is not a quick process. The main thing is not to waste precious time and try in every possible way to avoid death. It is better, of course, not to bring your condition to catastrophic consequences. The fact is that a certain category of people is prone to the formation of blood clots and, accordingly, pulmonary thromboembolism. As a rule, the risk group includes people who have crossed the 50-year age limit, are overweight, and have not given up bad habits. Such persons need to take preventive measures against thromboembolism of the pulmonary arteries.

Pulmonary embolism (translated from Greek as injection, insertion) is a severe complication of the respiratory and circulatory system, usually occurring in hospitalized patients. It is manifested by blockage by an embolus of the pulmonary artery or its branches that deliver blood from the heart to the lungs.

Causes and pathogenesis of embolism

Most often, a pulmonary embolism is caused by a blood clot. A thrombus is a pathological formation that is not found in a healthy body. It is a clot of glued platelets, plasma proteins and fibrinogen. As a rule, it occurs in the veins of the lower extremities and is provoked by:

• Staying in the same body position for a long time in disabled people who are bedridden, truck drivers and all people with sedentary work.
• Chronic diseases of the cardiovascular system that do not provide proper blood circulation in the periphery (hypertension, rheumatic carditis, arrhythmias with paroxysmal ventricular flutter, ischemic heart disease with acute myocardial infarction, cardiomyopathies, etc.).
• Varicose veins, thrombophlebitis.
• Childbirth and pregnancy.
• Oncological diseases.
• Recently undergone abdominal surgery and a long-term installed venous catheter.
• Sepsis, severe, debilitating chronic infections.
• Taking combined oral contraceptives.
• Systemic diseases (diabetes mellitus, metabolic syndrome).

The resulting thrombus breaks away from the vascular wall and begins to move along the bloodstream. Having passed from the periphery to the central veins, it reaches the heart, moving freely in the cavities of its chambers. Finally, it enters the pulmonary artery, which carries venous blood into the vessels of the lungs for oxygenation. The small diameter of the vessels does not allow the blood clot to move further; the pulmonary artery itself or its smaller branches become blocked. The symptoms of pulmonary embolism depend on the level and location of the lesion.

Clinical picture

Pulmonary embolism always develops suddenly. It is usually preceded by some action: coughing, straining, change in body position, etc.

If the blockage occurs with a small blood clot at the level of the small vessels of the lungs, shortness of breath becomes the main symptom of the disease. Very frequent and intermittent breathing, anxiety, fear of death, sometimes sharp pain in the chest, fainting, convulsions require immediate help.

There are small (switching off up to 25% of all vessels in the pulmonary circulation), submassive (up to 50%) and massive (up to 75%) forms of pulmonary embolism.

When the main trunk of the pulmonary artery is blocked, fatal symptoms caused by poor circulation and heart failure develop almost instantly. Suddenly severe cyanosis occurs and the person dies.

In addition to hemodynamic disturbances, pulmonary embolism causes infarction (death) of the lung. It has the following symptoms:

• chest pain that gets worse with inhalation and exhalation;
• paroxysmal cough;
• separation of sputum with blood;
• temperature increase.

All these manifestations are observed several hours after the onset of the disease, last three to five days and, with a favorable outcome, gradually disappear.

Diagnosis and treatment

Often the fact of pulmonary embolism is noted at the autopsy of a patient who died due to acute coronary syndrome. Due to the nonspecificity of symptoms and the critical condition of the patient, diagnostic studies are limited to a general examination and assessment of the condition. Then, when vital signs stabilize, doctors prescribe the following tests:

• general urine and blood tests;
• electrocardiography to study the biopotentials of the heart muscle;
• echocardiography for visual monitoring of hemodynamics and possible detection of emboli;
• angiography, which allows one to judge the location and extent of pulmonary vascular occlusion;
• perfusion scanning is one of the most reliable methods for diagnosing pulmonary embolism; it involves introducing special markers into the vascular bed that determine disturbances in the blood flow.

First aid for patients who have developed a pulmonary embolism is to call an ambulance and prompt hospitalization. Treatment of patients with pulmonary embolism is aimed at maintaining vital functions and restoring hemodynamics.

• connection to mechanical ventilation in the absence of spontaneous breathing, pulmonary infarction;
• oxygen therapy;
• anticoagulants: prevent the adhesion of blood cells, gradually eliminating the symptoms of blockage.

Maintaining body functions should be most effective in the first 12–14 hours of the disease, until the blood clot is resolved. Then a maintenance dose of anticoagulants is prescribed for up to 6 months under the supervision of general tests and a coagulogram.

In some cases, pulmonary embolism requires surgical treatment and an embolectomy (removal of a blood clot). In case of a heart attack, the affected lobe of the lungs is removed according to indications.

Measures to prevent pulmonary embolism for people with one or more risk factors:

• treatment of the underlying disease, healthy lifestyle, normalization of nutrition, sports, breathing exercises;
• for sedentary work - regular five minutes of physical activity;
• during long flights - drinking plenty of water, walking around the aircraft cabin to stretch your legs;
• for non-ambulatory patients - massage and exercise therapy on the lower extremities;
• early verticalization of patients who have suffered a stroke or myocardial infarction;
• during surgery, childbirth - use of compression stockings, which stimulate blood flow through the veins and prevent blood clots;
• after surgery - also wearing stockings, early activation, physical exercise;
• according to indications, prescribing anticoagulants (Heparin, Dextran), which thin the blood and prevent platelets from sticking together.

Unfortunately, the mortality rate from pulmonary embolism remains high. With occlusion of main vessels, the mortality rate reaches 30%.

Persons who received timely medical care should be observed by a local doctor for a long time. These patients are at high risk of recurrence of pulmonary vascular obstruction, so low doses of anticoagulant drugs are indicated for them. Patients may also experience progression of arterial hypertension.

Compliance with preventive measures, timely qualified medical care and further regular medical supervision are vital for patients with pulmonary embolism. These measures save life and prevent the development of complications of pulmonary embolism.

With fulminant pulmonary embolism, coronary circulatory failure with myocardial ischemia, decreased cardiac output, and cardiogenic shock develops over time.

The annual incidence of pulmonary embolism is 150-200 cases per 100,000 population, making it an emergency treatment and associated with a mortality rate of up to 11% in the first two weeks.

Most emboli are detached blood clots from peripheral veins (in more than 70% of cases, phlebothrombosis of the veins of the pelvis and lower extremities). Less commonly, a cardiac clot forms or the clots come from the superior vena cava.

Causes of pulmonary embolism

Risk factors include:

• Immobilization (surgery, accident/trauma, serious illness, neurological or internal organs, e.g. stroke, severe renal failure)
• Hypercoagulability, thrombophilia, previous venous thromboembolism
• Central venous catheter
• Pacemaker probes
• Malignant diseases, chemotherapy
• Heart failure
• Obesity
• Pregnancy
• Smoking
• Medications.

Symptoms and signs of pulmonary embolism

• Acute or sudden dyspnea, tachypnea
• Pleural pain, chest pain, angina complaints
• Hypoxemia
• Palpitation, tachycardia
• Arterial hypotension, shock
• Cyanosis
• Cough (partially also hemoptysis)
• Syncope
• Swollen neck veins

From a clinical point of view, it is necessary to distinguish between patients with high and low risk (hemodynamically stable = normotensive), since this is important for further diagnostic and therapeutic measures and for prognosis.

Diagnosis of pulmonary embolism

In hemodynamically unstable patients with suspected pulmonary embolism, the diagnosis should be confirmed as quickly as possible rather than simply undergoing extensive diagnostic testing before initiating therapy.

For this purpose they serve:

• Parameters of the cardiovascular system: tachycardia, arterial hypotension up to shock
• Imaging methods:
  • The “gold standard” for making (or excluding) the diagnosis of pulmonary embolism is a spiral CT scan of the lungs with a contrast agent (sensitivity up to 95%)
  • the alternative method of lung scintigraphy has lost its importance and is still used only in special situations
  • X-rays reveal only (if at all) nonspecific changes, such as atelectasis or infiltrates
• Blood gas analysis: hypoxemia
• Echocardiography plays an important role in emergency diagnosis! Depending on the degree of pulmonary embolism, signs of acute strain on the right ventricle or right ventricular dysfunction (dilatation, hypokinesia, paradoxical septal movements) are revealed, and sometimes the detection of floating blood clots in the right cavities of the heart.
• Laboratory data:
  • - D-dimers: indicators > 500 µg/l with fibrinolysis. A positive result is initially nonspecific; a negative result is quite likely to rule out pulmonary embolism.
  • sometimes troponin is elevated as a sign of myocardial ischemia.
  • Natriuretic peptide levels may increase with ventricular dilatation and are associated with worse outcome
• Ultrasound of the veins of the lower extremities

Differential diagnosis of pulmonary embolism

• Myocardial infarction
• Angina pectoris
• Heart failure
• Pneumothorax
• Pulmonary edema
• Bronchial asthma
• Pneumonia
• Pleurisy
• Intercostal neuralgia
• Aortic dissection
• Hydro- or hemopericardium.

Treatment of pulmonary embolism

If there is a high risk of hemodynamic instability or shock, thrombolysis therapy (or, if lytic therapy is contraindicated, surgical or endovascular embolectomy) should be started immediately. For hemodynamic instability, catecholamines are used. In hemodynamically stable patients (normotensive = low risk), early therapy with low molecular weight heparins or fondaparinux, adjusted to the patient's weight, is recommended.

The best therapeutic strategy for normotensive patients with right ventricular dysfunction has not yet been determined

Secondary prevention is provided by early anticoagulation with vitamin K antagonists (eg, Marcumar), initially cross-linked with heparin, until MHO is consistently in the therapeutic range between 2.0 and 3.0. In patients with secondary pulmonary embolism in whom the risk factor has been eliminated or treated, it is recommended that anticoagulation be continued for at least three months.

In case of “idiopathic” pulmonary embolism and unproblematic or stable anticoagulation, such therapy should be continued continuously.

Pulmonary embolism is a serious disease that requires immediate hospitalization, regardless of the form in which it manifests itself. You should know the possible symptoms of this disease, as well as measures to prevent it.

A common pathology of the cardiovascular system is pulmonary embolism, which has the generally accepted abbreviation PE. Pulmonary artery thrombosis involves blockage of both the main pulmonary artery and its branches by a blood clot. The primary site of thrombus formation is the veins of the lower extremities or pelvis, which are then carried through the bloodstream into the lungs.

The broader concept of “pulmonary embolism” implies blockage of the pulmonary artery not only by a thrombus, that is, a dense blood clot, but also by various other substances called an embolus.

Symptoms

Pulmonary embolism almost always has an acute onset, often coinciding with physical stress. An embolism can cause immediate death or cause varying symptoms depending on the size and level of the clot.

The following manifestations can be considered the primary symptoms of arterial embolism in the lungs:

• causeless debilitating weakness;
• uncharacteristic sweating;
• dry cough.

After some time, characteristic symptoms of pulmonary artery thrombosis appear, such as:

• the occurrence of shortness of breath and asthma attacks,
• fast shallow breathing;
• pain in the chest;
• with a deep breath, acute (pleural) pain is possible;
• increased body temperature;
• cough that produces foamy pink mucus - blood in the sputum.

However, these signs are not characteristic only of pulmonary embolism, which makes diagnosis extremely difficult, and pulmonary embolism may be accompanied by completely different manifestations:

• dizziness, fainting;
• nausea, vomiting;
• unconscious feeling of anxiety;
• increased sweating;
• cyanosis - blueness of the skin;
• tachycardia;
• epileptic seizures;
• signs of cerebral edema;
• swelling of the lower extremities and others.

In the case of extensive hemorrhage into the lung, the patient exhibits staining of the sclera and epidermis, characteristic of jaundice.

Causes of the disease

The most common cause of pulmonary embolism is a blood clot. And the most typical geography of origin is the veins of the pelvis or legs. For a blood clot to form, the venous blood flow must slow down, which occurs when the patient is stationary for a long time. In this case, with the start of movement, there is a threat of a blood clot breaking off, and the venous blood flow will quickly transfer the blood clot to the lungs.

Other variants of embolism - a fat particle and amniotic fluid (amniotic fluid) - are quite rare. They are capable of creating a blockage of small blood vessels in the lungs - arterioles or capillaries. In case of blockage of a significant number of small vessels, acute respiratory distress syndrome develops.

It is quite difficult to establish the cause of the formation of a blood clot, but the following factors often provoke the process:

• surgical intervention;
• injuries and damage to large veins of the chest;
• prolonged immobility associated with the patient’s condition;
• fracture of leg bones, fatty mass during fractures, when particles of bone marrow are carried into the circulatory system, where they can cause blockage;
• amniotic fluid;
• foreign bodies entered into the body as a result of injury;
• tumor cells as fragments of an overgrown malignant tumor;
• oil solutions for subcutaneous or intramuscular injections, when the needle enters a blood vessel;
• obesity and significant excess of optimal weight;
• increase in blood clotting rate;
• use of contraceptives.

Such a high mortality rate is due to the difficulties of diagnosis and the speed of the disease - most patients die almost in the first hours.

Research by pathologists shows that up to 80% of cases of pulmonary artery thrombosis are not diagnosed at all, which is explained by the polymorphism of the clinical picture. Studying the changes occurring in the vessels helps to study the processes occurring during pulmonary embolism. The essence of the process is clearly shown in the following pathological preparations:

• microscopic specimen showing stasis in the capillaries of the brain, the sludge phenomenon is clearly visible;
• microscopic specimen showing a mixed thrombus attached to the vein wall;
• a microslide on which the forming blood clot is clearly visible;
• microscopic specimen showing fat embolism of blood vessels in the lung;
• microscopic specimen showing destruction in lung tissue during hemorrhagic infarction.

In case of minor damage to the arteries, the remaining ones can cope with the blood supply to that part of the lung tissue where blood does not flow due to an embolus (thrombus or fatty particle), then tissue necrosis can be avoided.

Diagnostics

Examination of a patient with suspected thromboembolism has certain goals:

• confirm or refute the presence of embolism, since therapeutic measures are very aggressive and are used only with a confirmed diagnosis;
• determine the extent of the lesion;
• identify the localization of blood clots - especially important if surgical intervention is necessary;
• identify the source of the embolus to prevent relapse.

Due to the fact that pulmonary embolism occurs either asymptomatically or with symptoms characteristic of a number of other diseases, diagnosis of embolism of one or both lungs is carried out using instrumental methods.

CT scan

A reliable and reliable method that allows you to detect the presence of embolism and exclude other causes of lung pathology, such as inflammation, tumor or edema.

Perfusion scan

Pulmonary embolism can be excluded using this method. The method allows you to identify the presence of disturbances in the blood flow; scanning is carried out against the background of intravenous use of markers (albumin macrospheres, 997c) and is one of the most reliable methods for diagnosing pulmonary embolism.

Angiography

Angiography of pulmonary vessels is used to obtain information about the nature, extent, localization of occlusion and the possibility of re-embolism. The survey results are highly accurate.

Electrocardiography

The technique makes it possible to determine pulmonary embolism in cases of significant thrombus size. However, the results are not reliable enough in the case of organic age-related pathologies of the coronary arteries.

Echocardiography

The technique allows you to detect emboli in the arteries of the lungs and heart cavities. And also determine the cause of paradoxical embolism through the severity of hemodynamic disorders. However, this method, even with a negative result, cannot be a criterion for excluding the diagnosis of pulmonary embolism.

The use of instrumental diagnostic methods should be carried out comprehensively to increase the reliability of the result.

Treatment of the disease

Pulmonary embolism, despite the severity of the disease, is quite treatable. If in an acute form there is one task - saving the patient’s life, then further treatment has a number of specific tasks:

• normalization of blood flow dynamics;
• restoration of the pulmonary artery bed;
• measures to prevent relapse.

Surgical treatment

Massive pulmonary embolism requires emergency surgical intervention - embolectomy. The operation consists of removing a blood clot and can be performed using several methods:

• with the condition of temporary occlusion of the vena cava - the operation has a mortality rate of up to 90%;
• when artificial circulation is created, the mortality rate reaches 50%.

Therapeutic measures

Pulmonary embolism in terms of severity and prognosis depends on the degree of damage to the vascular bed and the level of hemodynamic disturbances. For minor disorders, anticoagulant treatment methods are used.

Anticoagulant therapy

The body is able to neutralize minor changes in hemodynamics and a small amount of vascular obstruction due to spontaneous lysis. The main focus of treatment is to prevent the development of venous thrombosis, the source of Ebola.

For this purpose, therapy is carried out with drugs of low molecular weight heparins - the drug has a good duration of action and bioavailability. The drug is administered twice a day under the skin in the abdominal area, and constant monitoring of the hematopoietic system is not necessary. Heparin therapy is carried out under the direct supervision of the attending physician, who also prescribes a dose and dosage regimen that is adequate to the patient’s condition.

Intravenous thrombolytics

The use of thrombolytics is indicated if the pulmonary embolism is quite massive, especially in the presence of age-related changes and poor adaptation of the body.

In the case of peripheral embolism, this technique is practically not used due to the high risk of allergic and hemorrhagic complications.

Thrombolytics are administered into the bloodstream through both small and large veins; in some cases, the drug is injected directly into the body of the blood clot.

Despite its effectiveness - 90% of patients show complete or partial lysis - the method is quite dangerous and is associated with severe complications, such as bleeding or hemorrhagic complications.

For this reason, the technique is prohibited for use in a number of cases:

• postoperative patients;
• immediately after childbirth;
• traumatic injuries.

If necessary, for these categories of patients, thrombolytics can be used 10 days after surgery/birth/trauma.

After thrombolytic therapy, treatment with anticoagulants is mandatory.

Preventive measures

The best prevention of a disease such as pulmonary embolism can be considered physical and pharmacological measures to prevent thrombosis.

Physical measures to prevent embolism for inpatients include:

• reducing bed rest time;
• use of exercise equipment that simulates walking or cycling;
• limb massage;
• therapeutic exercises.

Pharmacological measures involve the use of coagulants when there is a high probability of complications. All drugs must be prescribed by the attending physician in terms of use and dosages.

The use of preventive measures to prevent the formation of venous blood clots will help to significantly reduce the percentage of pulmonary embolism