Toxic gases are those that dissolve when inhaled in the water of Atemwegschleimhaut and cause an inflammatory reaction, usually due to the release of acidic or alkaline radicals. Tear gas exposure predominantly affects the respiratory tract and causes tracheitis, bronchitis, and bronchiolitis. Other inhaled substances can be directly toxic (z. B. cyanide, carbon monoxide), or cause damage simply by displacement of O2 and eliciting an asphyxia (eg. As methane, carbon dioxide).
(Pulmonary Chemical warfare agents.) Toxic gases are those that dissolve when inhaled in the water of Atemwegschleimhaut and cause an inflammatory reaction, usually due to the release of acidic or alkaline radicals. Tear gas exposure predominantly affects the respiratory tract and causes tracheitis, bronchitis, and bronchiolitis. Other inhaled substances can be directly toxic (z. B. cyanide, carbon monoxide), or cause damage simply by displacement of O2 and eliciting an asphyxia (eg. As methane, carbon dioxide). The effects of inhaled irritants are dependent upon the extent and duration of exposure and the specific substance. Chlorine, phosgene, sulfur dioxide, chlorine or hydrogen sulfide, nitrogen dioxide, ozone and ammonia are among the most important irritant gases. Hydrogen sulfide is also a potent cytotoxin that blocks the cytochrome system and inhibits cellular respiration. A frequent exposure involves mixing ammonia with household cleaning products containing bleach; pepper spray chloramine is released. Acute exposure Acute exposure to irritative-toxic irritant gases over a short period is typical of industrial accidents caused by a defective valve or a defective pump in a gas container or during the transport of gases. However, many people may be exposed and affected. The release of methyl isocyanate from a chemical plant in Bhopal, India, killed> 2000 people in the year 1984th The extent of the damage to the respiratory tract depends on the concentration of the gas and its solubility. Readily water-soluble gases (eg. Chlorine, ammonia, sulfur dioxide, hydrogen chloride), which dissolve in the upper respiratory tract, cause immediate irritation of the mucous membranes, which can alert people to flee from the danger zone. Permanent damage of the upper respiratory tract, the distal airways and the lung parenchyma is possible only if the escape from the gas source is obstructed. Less soluble gases (eg. As nitrogen dioxide, phosgene, ozone) can be solved only when they have a good position in the airways, often until they reach the lower respiratory tract. These substances less likely to cause early warning signs (phosgene in low concentrations has a pleasant smell), more likely to cause severe bronchiolitis, and often have a delay of ? 12 hours before symptoms develop pulmonary edema. Complications The most serious immediate complication is acute respiratory distress syndrome (ARDS), which usually occurs within 24 hours. Patients with significant involvement of the lower respiratory tract can develop a bacterial infection. Ten to 14 days after acute exposure of certain substances (eg. As ammonia, nitrogen oxides, sulfur dioxide, mercury), some patients develop bronchiolitis obliterans, the progressiert to acute febrile respiratory disease. A bronchiolitis obliterans organizing pneumonia (BOOP) may result when accumulates within the body’s own repair mechanisms granulation tissue in the terminal airways and the Alveolengängen. A minority of these patients develop soluble irritant gases cause serious chemical burns and other manifestations of irritation of eyes, nose, throat, trachea and bronchi late Lungenfibrose.Symptome and discomfort. Significant cough, hemoptysis, wheezing, retching, and dyspnea are common. The upper airway can be obstructed by edema, increased secretion production or laryngospasm. The severity is generally dose-dependent. Non-soluble gases cause less acute symptoms, but can lead to dyspnea or cough. Patients who develop an acute febrile respiratory illness, have a worsening dyspnea and increased O2 Bedarf.Diagnose exposure history chest x-ray spirometry and lung volume tests Diagnosis is usually obvious by the history. Patients should perform a chest x-ray and pulse oximetry. Patchy or confluent consolidation of the alveoli in the chest x-ray is usually an indication of a pulmonary edema. Spirometry and lung volume tests are performed. Obstructive anomalies are most common, but restrictive anomalies may outweigh after exposure to high doses of chlorine. CT is used to evaluate patients with up late developing symptoms. Those with bronchiolitis obliterans, the progressiert to respiratory failure manifest a pattern of thickening of the bronchioles and a mixed mosaic of Hyperinflation.Prognose Most people recover completely, but some have permanent lung damage with reversible airway obstruction (reactive airways dysfunction syndrome) or restrictive abnormalities and pulmonary fibrosis ; Smokers are at greater risk ausgesetzt.Therapie Keep away from additional exposure and 24-hour observation bronchodilators and supplemental O2 Sometimes inhaled epinephrine racemate, endotracheal intubation and artificial respiration Treatment depends not so much by the inhaled agent, but according to the symptoms. Patients should be removed to fresh air and will also receive O2. The treatment is aimed at ensuring adequate oxygenation and ventilation of the alveoli. In milder cases Bronchodilators and O2 therapy may suffice. Severe airway obstruction is inhaled epinephrine racemate, endotracheal intubation (Restoring and Backing up the airways: Endotracheal intubation) treated or tracheostomy and artificial ventilation. The efficacy of corticosteroid treatment (eg. Prednisone 45-60 mg once daily for 1-2 weeks) is unproven, but is often used. Due to the risk of an acute febrile respiratory disease, all patients should be monitored with Atemwegsymptomen by toxic inhalation for 24 h. After treatment the acute phase doctors should focus on the development of RADS, bronchiolitis obliterans with or without organizing pneumonia, pulmonary fibrosis and acute febrile respiratory illness delayed-type achten.Prävention The most important preventive measure is proper precautions when handling gases and chemicals. The availability of adequate breathing apparatus (. Eg respirator helmets with a fan) for rescue workers is also of great importance; Helpers who rush without protective clothing offerings for help, endangering yourself. Chronic exposure low concentrated continuous or intermittent exposure to irritant gases or chemical vapors can cause chronic bronchitis, although the significance of such exposures in particular in smokers is difficult to judge. Chronic inhalation exposure with some agents (for. Example, bis [chloromethyl] ether, certain metals) causes lung and other malignant tumors (eg. B. angiosarcoma the liver by vinyl chloride monomer). Important points irritant gas exposure predominantly affects the respiratory tract and cause tracheitis, bronchitis and bronchiolitis. Complications of acute exposure to ARDS, bacterial infections, and bronchiolitis obliterans (sometimes leads to pulmonary fibrosis) include. The diagnosis of acute exposure is usually based on history obvious, but pulse oximetry, chest x-ray, spirometry and lung volume assessment should be conducted. Acute exposure should treated supportive and patient be observed for 24 hours.