This review looks at the potential causes, diagnoses, and possible treatments for three asphyxiant gases: carbon monoxide, hydrogen cyanide, and hydrogen sulfide, Exposure to these gases can lead to central nervous system depression, unconsciousness, and death due to tissue hypoxia. These gases are among the most common causes of fatalities related to toxic gas poisoning, with carbon monoxide responsible for 36% and hydrogen sulfide 7.7%. It is necessary to remove victims affected by poisoning immediately from the source of the toxic gas, administer oxygen, and assess their stability. As symptoms of these gases can differ widely, ranging from broad and unspecific to highly morbid, and may require different levels of care, the correct diagnosis should also rely on inferences from the patient history and the context of the admission, including evidence of fire and chemical reactions. Normobaric oxygen and hyperbaric oxygen are the two main treatments for carbon monoxide, although studies have been inconclusive in regards to the effectiveness of hyperbaric oxygen. The Cyanokit (containing hydroxocobalamin) is considered to be more effective for hydrogen cyanide when compared with the Cyanide Antidote Kit due to the former’s low toxicity and high effectiveness. Hydrogen sulfide is often used as a suicide agent, the mortality of which is close to 100%. Figures show the mechanisms by which the asphyxiant gases carry out their negative effects on the human body. Tables show the half-life of carboxyhemoglobin with oxygen therapy and a comparison between the Cyanide Antidote Kit and the Cyanokit.
This review contains 3 figures, 13 tables, and 44 references.
Keywords: Inhalation, poisoning, carbon monoxide, cyanide, methemoglobin, carboxyhemoglobin, hydrogen sulfide, smoke
Oxidation Treatment of Dilute Hydrogen Cyanide. On the Formation of Carbon Monoxide and Carbon Dioxide.