Contents
What is pulmonary edema?
Pulmonary edema is a severe pathological condition associated with a massive release of non-inflammatory transudate from the capillaries into the interstitium of the lungs, then into the alveoli. The process leads to a decrease in the functions of the alveoli and a violation of gas exchange, hypoxia develops. The gas composition of the blood changes significantly, the concentration of carbon dioxide increases. Along with hypoxia, severe depression of the functions of the central nervous system occurs. Exceeding the normal (physiological) level of interstitial fluid leads to edema.
The interstitium contains: lymphatic vessels, connective tissue elements, intercellular fluid, blood vessels. The entire system is covered by the visceral pleura. The branched hollow tubules and tubes are the complex that makes up the lungs. The entire complex is immersed in the interstitium. The interstitium is formed by plasma leaving the blood vessels. The plasma is then reabsorbed back into the lymphatic vessels that empty into the vena cava. According to this mechanism, the intercellular fluid delivers oxygen and necessary nutrients to the cells, removes metabolic products.
Violation of the amount and outflow of interstitial fluid leads to pulmonary edema:
when an increase in hydrostatic pressure in the blood vessels of the lungs caused an increase in interstitial fluid, hydrostatic edema occurs;
the increase was due to excessive plasma filtration (for example: with the activity of inflammatory mediators), membrane edema occurs.
Assessment of
Depending on the rate of transition of the interstitial stage of edema to the alveolar stage, the patient’s condition is assessed. In the case of chronic diseases, edema develops more gradually, more often at night. Such edema is well stopped by drugs. Edema associated with mitral valve defects, myocardial infarction, and damage to the lung parenchyma grows rapidly. The condition is rapidly deteriorating. Edema in an acute form leaves very little time to react.
Prognosis of the disease
The prognosis of pulmonary edema is unfavorable. It depends on the reasons that actually caused the edema. If the edema is non-cardiogenic, it responds well to treatment. Cardiogenic edema is difficult to stop. After prolonged treatment after cardiogenic edema, the survival rate for a year is 50%. With a lightning-fast form, it is often not possible to save a person.
With toxic edema, the prognosis is very serious. Favorable prognosis when taking large doses of diuretics. It depends on the individual reaction of the body.
Diagnostics
The picture of any type of pulmonary edema is bright. Therefore, the diagnosis is simple. For adequate therapy, it is necessary to determine the causes that caused the edema. Symptoms depend on the form of edema. The lightning-fast form is characterized by rapidly increasing suffocation and respiratory arrest. The acute form has more pronounced symptoms, in contrast to the subacute and protracted.
Symptoms of pulmonary edema
The main symptoms of pulmonary edema include:
frequent coughing;
increasing hoarseness;
cyanosis (face and mucous membranes acquire a bluish tint);
increasing suffocation;
tightness in the chest, pain of a pressing nature;
increased breathing;
dizziness, weakness;
bubbling rales are heard;
with increasing cough – foamy pink sputum;
when the condition worsens, sputum is discharged from the nose;
the person is frightened, the mind may be confused;
perspiration, sweat cold and clammy;
fear of death;
increased heart rate up to 200 beats per minute. It can easily turn into life-threatening bradycardia;
drop or jump in blood pressure.
By itself, pulmonary edema is a disease that does not occur on its own. Many pathologies can lead to edema, sometimes not at all associated with diseases of the bronchopulmonary and other systems.
Causes of pulmonary edema
Causes of pulmonary edema include:
Sepsis. Usually it is the penetration into the bloodstream of exogenous or endogenous toxins;
Pneumonia;
Overdose of certain (NSAIDs, cytostatics) drugs;
Radiation damage to the lungs;
Overdose of narcotic substances;
Myocardial infarction, heart disease, ischemia, hypertension, any heart disease in the stage of decompensation;
Stagnation in the right circle of blood circulation that occurs with bronchial asthma, emphysema and other pulmonary diseases;
A sharp or chronic decrease in protein in the blood. Hypoalbuminemia occurs with cirrhosis of the liver, nephrotic syndrome and other pathologies of the kidneys;
Infusions in large volumes without forced diuresis;
Poisoning with toxic gases;
Poisons;
Aspiration of the stomach;
Shock with serious injuries;
Enteropathy;
Being at high altitude;
Acute hemorrhagic pancreatitis.
Types of pulmonary edema
There are two types of pulmonary edema: cardiogenic and non-cardiogenic. There is also a 3rd group of pulmonary edema (refers to non-cardiogenic) – toxic edema.
Cardiogenic edema (cardiac edema)
Cardiogenic edema is always caused by acute left ventricular failure, obligatory stagnation of blood in the lungs. Myocardial infarction, heart defects, angina pectoris, arterial hypertension, left ventricular failure are the main causes of cardiogenic edema. To link pulmonary edema with chronic or acute heart failure, lung capillary pressure is measured. In the case of a cardiogenic type of edema, the pressure rises above 30 mm Hg. Art. Cardiogenic edema provokes extravasation of fluid into the interstitial space, further into the alveoli. Attacks of interstitial edema are observed at night (paroxysmal dyspnea). The patient is out of breath. Auscultation reveals harsh breathing. Breathing is increased on exhalation. Choking is the main symptom of alveolar edema.
Cardiogenic edema is characterized by the following symptoms:
suffocation;
growing cough;
inspiratory dyspnea. The patient is characterized by a sitting position, in the prone position, shortness of breath increases;
hyperhydration of tissues (swelling);
dry whistling, turning into moist gurgling rales;
separation of pink foamy sputum;
acrocyanosis;
unstable blood pressure. It’s hard to bring it down. A decrease below normal can lead to bradycardia and death;
tachycardia;
severe pain behind the sternum or in the chest area;
fear of death;
On the electrocardiogram, hypertrophy of the left atrium and ventricle is read, sometimes blockade of the left leg of the His bundle.
Hemodynamic conditions of cardiogenic edema
violation of the systole of the left ventricle;
diastolic dysfunction;
systolic dysfunction.
The leading cause of cardiogenic edema is left ventricular dysfunction.
Cardiogenic edema should be differentiated from non-cardiogenic edema. With a non-cardiogenic form of edema, changes in the cardiogram are less pronounced. Cardiogenic edema proceeds more rapidly. The time for emergency care is less than with other types of edema. The lethal outcome is more often with cardiogenic edema.
Toxic pulmonary edema
Toxic edema has certain specific features that promote differentiation. There is a period here when there is no edema itself yet, there are only reflex reactions of the body to irritation. Burns of lung tissues, burns of the respiratory tract cause reflex spasm. This is a combination of symptoms of damage to the respiratory organs and the resorptive effects of toxic substances (poisons). Toxic edema can develop regardless of the dose of medication that caused it.
Medicines that can cause pulmonary edema:
narcotic analgesics;
many cytostatics;
diuretics;
radiopaque preparations;
non-steroidal anti-inflammatory drugs.
Risk factors for the occurrence of toxic edema are advanced age, prolonged smoking.
Has 2 forms developed and abortive. There is a so-called “silent” edema. It can be detected on x-ray examination of the lungs. There is practically no definite clinical picture in such edema.
characterized by periodicity. Has 4 periods:
reflex disorders. It is characterized by symptoms of irritation of the mucous membranes: lacrimation, cough, shortness of breath. The period is dangerous by stopping breathing and cardiac activity;
Latent period of subsidence of irritations. May last 4-24 hours. Characterized by clinical well-being. Careful examination may show signs of impending edema: bradycardia, emphysema;
Direct pulmonary edema. The course is sometimes slow, up to 24 hours. Most often, the symptoms increase in 4-6 hours. During this period, the temperature rises, there is neutrophilic leukocytosis in the blood count, there is a danger of collapse. The developed form of toxic edema has a fourth period of completed edema. The completed period has “blue hypoxemia”. Cyanosis of the skin and mucous membranes. The completed period increases the respiratory rate to 50-60 times per minute. The bubbling breath is heard in the distance, sputum mixed with blood. Increases blood clotting. gaseous acidosis develops. “Gray” hypoxemia is characterized by a more severe course. Vascular complications join. The skin takes on a pale grayish tint. The limbs get cold. Thready pulse and falling to critical values of arterial pressure. This condition is facilitated by physical activity or improper transportation of the patient;
Complications. When leaving the period of direct pulmonary edema, there is a risk of developing secondary edema. It is associated with left ventricular failure. Pneumonia, pneumosclerosis, emphysema are common complications of drug-induced toxic edema. At the end of the 3rd week, a “secondary” edema may occur against the background of acute heart failure. Rarely there is an exacerbation of latent tuberculosis and other chronic diseases. Depression, drowsiness, asthenia.
With rapid and effective therapy, a period of reverse development of edema occurs. It does not apply to the main periods of toxic edema. It all depends on the quality of the assistance provided. Cough and shortness of breath decrease, cyanosis decreases, wheezing in the lungs disappears. On x-ray, the disappearance of large, then small foci is noticeable. The picture of peripheral blood is normalized. The recovery period after toxic edema can be several weeks.
In rare cases, toxic edema can be caused by taking tocolytics. Edema can be catalyzed by: large volumes of intravenous fluid, recent treatment with glucocorticoids, multiple pregnancy, anemia, unstable hemodynamics in a woman.
Clinical manifestations of the disease:
The key symptom is respiratory failure;
severe shortness of breath;
Cough;
severe chest pain;
Cyanosis of the skin and mucous membranes;
Arterial hypotension in combination with tachycardia.
From cardiogenic edema, toxic edema differs in a protracted course and the content of a small amount of protein in the fluid. The size of the heart does not change (rarely changes). Venous pressure is often within the normal range.
Diagnosis of toxic edema is not difficult. An exception is bronchorrhea in case of FOS poisoning.
Non-cardiogenic pulmonary edema
Occurs due to increased vascular permeability and high fluid filtration through the wall of the pulmonary capillaries. With a large amount of fluid, the work of blood vessels deteriorates. The fluid begins to fill the alveoli and gas exchange is disturbed.
Causes of non-cardiogenic edema:
renal artery stenosis;
pheochromocytoma;
massive renal failure, hyperalbuminemia;
exudative enteropathy;
pneumothorax can cause unilateral non-cardiogenic pulmonary edema;
severe attack of bronchial asthma;
inflammatory diseases of the lungs;
pneumosclerosis;
sepsis;
aspiration of gastric contents;
cancerous lymphangitis;
shock, especially with sepsis, aspiration and pancreatic necrosis;
cirrhosis of the liver;
radiation;
inhalation of toxic substances;
lungs’ cancer;
large transfusions of drug solutions;
in elderly patients who take acetylsalicylic acid preparations for a long time;
drug addict.
For a clear distinction between edema, the following measures should be taken:
study the history of the patient;
apply methods of direct measurement of central hemodynamics;
radiography;
to assess the affected area in myocardial ischemia (enzyme tests, ECG).
For differentiation of non-cardiogenic edema, the main indicator will be the measurement of wedge pressure. Normal cardiac output, positive results of wedge pressure indicate the non-cardiogenic nature of the edema.
Sequelae of pulmonary edema
When the edema is stopped, it is too early to finish the treatment. After an extremely severe condition of pulmonary edema, serious complications often occur:
accession of a secondary infection. The most common is pneumonia. Against the background of reduced immunity, even bronchitis can lead to adverse complications. Pneumonia against the background of pulmonary edema is difficult to treat;
hypoxia, characteristic of pulmonary edema, affects the vital organs. The most serious effects can affect the brain and cardiovascular system – the effects of edema may be irreversible. Violation of cerebral circulation, cardiosclerosis, heart failure without powerful pharmacological support lead to death;
ischemic damage to many organs and systems of the body;
pneumofibrosis, segmental atelectasis.
Emergency care for pulmonary edema
Required for every patient with signs of pulmonary edema. Highlights of emergency care:
the patient needs to be given a semi-sitting position;
aspiration (removal) of foam from the upper respiratory tract. Aspiration is performed by inhaling oxygen through 33% ethanol;
urgent inhalation of oxygen (oxygen therapy);
elimination of acute pain syndrome with the help of neuroleptics;
restoration of heart rhythm;
correction of electrolyte balance;
normalization of acid-base balance;
normalization of hydrostatic pressure in the pulmonary circulation. Narcotic analgesics are used. They depress the respiratory center, relieve tachycardia, reduce venous blood flow, lower blood pressure, reduce anxiety and fear of death;
vasodilators – lower vascular tone, intrathoracic blood volume. Nitroglycerin preparations facilitate the outflow of blood from the lungs, acting on peripheral vascular resistance;
imposition of venous tourniquets on the lower extremities. The procedure is necessary to reduce the CTC – an old effective method;
the appointment of diuretics for dehydration of the lungs;
the appointment of cardiac glycosides to increase myocardial contractility;
immediate hospitalization.
Major complications after emergency care
These complications include:
development of a lightning-fast form of edema;
intense foam production can provoke airway obstruction;
depression (oppression) of breathing;
tachyarrhythmia, asystole;
angio pain. Such pain is characterized by an unbearable pain syndrome, the patient may experience a pain shock that worsens the prognosis;
inability to stabilize blood pressure. Often, pulmonary edema occurs against the background of low and high blood pressure, which can alternate within a large amplitude. The vessels will not be able to withstand such a load for a long time and the patient’s condition worsens;
increase in pulmonary edema against the background of high blood pressure.
Treatment of pulmonary edema
It boils down to one thing – the swelling should be removed as soon as possible. Then, after intensive therapy of the pulmonary edema itself, funds are prescribed to treat the disease that provoked the edema.
Algorithm for the treatment of pulmonary edema
The treatment algorithm itself can be divided into 7 stages:
sedative therapy;
foam extinguishing;
vasodilator therapy;
diuretics;
cardiac glycosides in cardiogenic edema and glucocorticoids in non-cardiogenic;
blood exfusion;
after relief of edema – hospitalization for the treatment of the underlying disease.
For relief of 80% of cases of pulmonary edema, morphine hydrochloride, furosemide and nitroglycerin are sufficient.
Then the treatment of the underlying disease begins:
in case of liver cirrhosis, hyperalbuminemia, a course of hepatoprotectors is prescribed;
if the edema is provoked by pancreatic necrosis, drugs are prescribed that depress the pancreas, then stimulate the healing of necrosis, along with powerful enzyme therapy;
complex therapy of myocardial infarction;
with bronchopulmonary diseases, a course of antibiotics is needed;
with a severe asthma attack, glucocorticosteroids, mucolytics, expectorants, bronchodilators are prescribed;
in case of toxic shock, antihistamines are prescribed;
The prognosis after suffering pulmonary edema is rarely favorable. For survival within a year, it is necessary to be under observation. Effective therapy of the underlying disease that caused pulmonary edema significantly improves the patient’s quality of life and prognosis.
Therapy of pulmonary edema is primarily reduced to the actual removal of the edema itself. Therapy in the hospital is aimed at treating the disease that provoked the edema.