Medical expert of the article
New publications
Lung inflammation caused by inhalation of toxic substances
Last reviewed: 23.04.2024
All iLive content is medically reviewed or fact checked to ensure as much factual accuracy as possible.
We have strict sourcing guidelines and only link to reputable media sites, academic research institutions and, whenever possible, medically peer reviewed studies. Note that the numbers in parentheses ([1], [2], etc.) are clickable links to these studies.
If you feel that any of our content is inaccurate, out-of-date, or otherwise questionable, please select it and press Ctrl + Enter.
Acute exposure to toxic substances
Short-term exposure to high concentrations of toxic gases is typical for occupational accidents, due to defects in valves or pumps in the gas tank or during gasoline transportation. In this case, a large number of people can be exposed and affected. Chlorine, phosgene, sulfur dioxide, hydrogen dioxide or sulphide, nitrogen dioxide, ozone and ammonia are among the most important gases of irritating action.
The defeat of the respiratory system is related to the size of the inhaled particles and the solubility of the gas. Most water-soluble gases (eg, chlorine, ammonia, sulfur dioxide, hydrogen chloride) immediately causes irritation of the mucous membrane, which can cause the affected to leave the affected area. Significant damage to the upper parts of the respiratory tract, distal airways and lung parenchyma occurs only when the victim can not leave the source of exposure. Less soluble gases (eg, nitrogen dioxide, phosgene, ozone) do not cause early warning symptoms and are more likely to cause severe bronchiolitis with pulmonary edema or without. With intoxication with nitrogen dioxide (which occurs in the fillers of bins and welders), there may be a delayed (up to 12 h) development of symptoms of pulmonary edema.
[8], [9], [10], [11], [12], [13]
Chronic exposure to toxic substances
Continuous or intermittent exposure to low levels of irritating gases or chemical vapors can lead to chronic bronchitis, although the role of such exposure is particularly difficult to prove in smokers.
Chronic inhalation exposure to certain agents (eg bichloromethyl ether or certain metals) causes lung cancer or other localization (eg, angiosarcoma of the liver after exposure to a vinyl chloride monomer, mesothelioma when exposed to asbestos).
Symptoms of lung damage caused by inhalation of toxic substances
Soluble irritating gases cause severe hyperemia and other manifestations of eye, nose, throat, trachea and major bronchial irritation. Cough, hemoptysis, wheezing, vomiting and shortness of breath are noted. The severity of the lesion depends on the dose. Insoluble gases cause fewer immediate symptoms, but can cause shortness of breath or cough.
The diagnosis is usually obvious from an anamnesis; The nature of care depends not on the type of inhaled substance, but rather on the symptoms. The upper respiratory tract can be blocked by swelling, secretion and / or laryngospasm. The detection of focal or drainage alveolar consolidation in chest radiography usually indicates pulmonary edema. The presence of any of these signs indicates the need for preventive endotracheal intubation.
Treatment of lung lesions caused by inhalation of toxic substances
Immediate assistance consists in removal from the source of the lesion, observation and maintenance therapy. If possible, the victim should be moved to fresh air and he must be given an additional O 2. Treatment is aimed at maintaining sufficient gas exchange, adequate oxygenation and alveolar ventilation. Severe airway obstruction requires the administration of inhaled racemic adrenaline, endotracheal intubation or tracheostomy, and artificial ventilation of the lungs, if necessary. Bronchodilators and oxygen therapy may be sufficient in less severe cases. The effectiveness of therapy with glucocorticoids (for example, prednisolone 45-60 mg once a day for 1-2 weeks) is difficult to prove, but it is often used empirically.
After an acute phase, doctors should be ready to develop a reactive airway dysfunction syndrome, obliterating bronchiolitis with or without organized pneumonia, pulmonary fibrosis and delayed ARDS. Because of the risk of ARDS, any patient with acute upper respiratory tract infection after inhalation of toxic aerosols or gases should be observed within 24 hours.
How to prevent lung damage caused by inhalation of toxic substances?
Caution in working with gases and chemicals is the most important preventative measure. The presence of adequate respiratory protection (for example, gas masks with an isolated supply of air) is also very important; rescuers without protective devices that are in a hurry to release the victim, often suffer themselves, receiving acute and chronic respiratory disease.
What prognosis are lung lesions caused by the inhalation of toxic substances?
Most people recover completely. Bacterial infections that occur frequently are the most serious complication. Some develop acute respiratory distress syndrome (ARDS), usually within 24 hours. Obliterating bronchiolitis leading to respiratory failure may develop 10-14 days after a brief exposure to ammonia, nitric oxide, sulfur dioxide and mercury. This type of lesion is manifested by a mixed obstructive and restrictive type of PDD and is detected in CT as a thickening of bronchioles and mosaic increased airiness.
Obliterating bronchiolitis with organizing pneumonia may follow if granulation tissue develops in the distal airways and alveolar ducts during the recovery period. In more rare cases, ARDS may develop with or without pulmonary fibrosis.
Sometimes severe lesions lead to reversible airway obstruction (a syndrome of reactive airway dysfunction), which lasts more than 1 year, slowly resolving in some cases. Smokers may be more susceptible to persistent toxic lung damage. The defeat of the lower respiratory tract can make breathing more difficult for a longer time, especially after exposure to ammonia, ozone, chlorine and gasoline vapors.