Smoke inhalation injury, also known as inhalation injury, is a leading cause of death. Smoke inhalation injury describes the damage caused to the respiratory tract and lung tissue when smoke or chemicals are inhaled and passed through the airway.
Smoke inhalation is associated with burn injuries and pulmonary complications. Over a 10-year period in the United States, inhalation injury was responsible for 77 percent of deaths caused by fires while the majority of these deaths were the result of carbon monoxide poisoning.
This article discusses the causes, clinical features, and health consequences of smoke inhalation.
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Inhalation injury is caused by breathing in toxic substances such as smoke, chemical irritants, and poisonous gases. Extreme heat can also cause damage to the airway. Toxic substances produced by combustion or pyrolysis are some of the most common causes of inhalation injury and pulmonary complications, with carbon monoxide and hydrogen cyanide among the most dangerous.
Carbon monoxide poisoning
Carbon monoxide is a colorless, odorless gas often referred to as the “silent killer” due to the fact that it is imperceptible but deadly. Symptoms of carbon monoxide poisoning include headache, dizziness, nausea, and fainting. High levels of carbon monoxide can cause slowed respiration, coma, and death.
Hydrogen cyanide poisoning
Hydrogen cyanide is the gaseous form of Cyanide. It is a colorless gas with an odor similar to that of bitter almonds. It is commonly produced during house fires when natural and synthetic fibers such as wool, silk, and nylon are partially burned. The symptoms of hydrogen cyanide poisoning include headache, anxiety, confusion, abdominal pain, hypertension, flushed skin, and tachycardia (abnormally rapid heart rate). Hydrogen cyanide poisoning can cause seizures, coma, and death.
Smoke inhalation and heat can cause thermal injury to the upper airway, which is the area above the vocal cords. Upper-airway injury can manifest as erythema (abnormally red skin), edema (swelling), and ulcerations, as well as distortion and compression of the airway. Fluid therapy may be required to treat burn shock associated with such injuries.
The tracheobronchial tree can be injured by smoke chemicals, as well as toxic inhalation of noxious gases, liquids, and direct airway fire. Symptoms include persistent coughing and wheezing and soot-containing mucus.
Pneumonia is not a direct result of smoke inhalation, but it is a possible complication. If inhalation injury is not properly treated and the airway is not cleared, airway obstruction and lung collapse can occur and lead to pneumonia.
Symptoms and diagnosis
Smoke inhalation injury is suspected when a patient has a history of exposure to smoke, heat, or chemical substances, as well as supporting symptoms. Factors such as the duration of smoke exposure, whether exposure took place in a confined space, and whether there was a loss of consciousness are all taken into account when diagnosing and treating inhalation injury. The possibility of carbon monoxide poisoning is always suspected until it can be excluded using the relevant tests.
Diagnosis of inhalation injury involves visually examining the airways for signs of smoke inhalation, such as blistering, edema, and ulceration. This can be done through nasopharyngoscopy or direct laryngoscopy.
Symptoms associated with smoke inhalation include:
- Breathing difficulty
- Shortness of breath
- Persistent cough
- Mucus production
- Facial burns
Hospitalization is often required for treating smoke inhalation. Airway management is a key part of initial management for inhalation injuries. This may involve endotracheal intubation or, in more serious cases, placement of a tracheostomy. Pulmonary hygiene may also be implemented to clear the airways of mucus and to prevent inflammation.
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