Pulmonary edema is a very serious pathological condition in which the fluid content in the lung tissue exceeds the normal level due to an increase in the difference between hydrostatic and colloid osmotic pressures in the capillaries of the lungs. As a result, there is a sharp violation of gas exchange, a change in the gas composition of the blood, the development of hypoxia and severe suppression of the central nervous system.
Signs and types of pulmonary edema
The main signs of pulmonary edema are:
- cyanosis;
- shortness of breath ;
- increasing suffocation;
- cough with the release of frothy bloody sputum;
- strong wheezing .
Depending on the trigger mechanisms, there are two types of pulmonary edema:
- Hydrostatic - occurs in pathologies that cause an increase in hydrostatic pressure in the blood vessels of the lungs and the release of the liquid substance of blood into the lung tissue in an amount greater than the possibility of its removal through the lymphatic vessels.
- Membranogenic - occurs in cases where certain pathological syndromes cause an increase in the permeability of the capillaries of the lungs.
In addition, depending on the causes, non-cardiogenic pulmonary edema is distinguished, as well as cardiogenic pulmonary edema associated with heart disease.
Causes of hydrostatic pulmonary edema in humans
The main factors causing pulmonary edema due to increased intracapillary pressure are:
- Various heart dysfunctions - heart rhythm disturbances, a significant increase in the volume of circulating blood, a decrease in contractility of the left ventricle, stenosis of the mitral valve, etc.
- Violation of pulmonary-venous circulation due to the narrowing of the veins, caused by a spasm of neurogenic etiology.
- Blockage of the pulmonary artery or its branches, which can be caused by the entry of blood clots into blood vessels (most often these are blood clots that form in the veins of the pelvis or lower extremities), air bubbles, fat drops (released into the blood from the bone marrow, for example, in fractures) , as well as septic emboli.
- Obstruction of the respiratory tract - due to diseases of the trachea, bronchi, lungs, as well as obstruction of airways by various foreign substances.
- Disturbance of lymph circulation due to obstruction of lymph vessels due to lung tumors, air or gas accumulation in the pleural cavity.
The causes of the membrane-induced pulmonary edema
The main causes of membrane edema are:
- Acute respiratory distress syndrome - inflammatory damage of the lungs due to direct or indirect damage to the lungs, which is most often associated with chest injuries, sepsis, pancreatitis (as a result of hemodynamic disorders).
- Aspiration syndrome - due to the throwing of the contents of the stomach into the airways, water ingress from drowning, etc.
- Intoxication syndrome - pulmonary edema due to exposure to toxic substances released by pathogenic microorganisms in various infectious diseases, as well as renal failure.
- Inhalation syndrome - poisoning with toxic gases (chlorine, phosgene, etc.),
steams of mercury, smoke, etc.
Treatment of pulmonary edema
The tactics of treating pulmonary edema are determined by the causes that caused it. However, even before the patient is transported to a medical institution, urgent measures must be taken. Patients are taken to special intensive care units, which are equipped with diagnostic equipment. Therapeutic measures are carried out under constant monitoring of hemodynamic parameters and characteristics of external respiration. Essential medicines are introduced through the central venous access, for which the catheter is inserted into the subclavian vein.