Chapter 91 - Acute and Long-Term Toxicity Caused by Addictive Inhalation of Nitrous Oxide and Impact on Neuropathology

Abstract

Nitrous oxide (N2O) is used in many different areas of life. Described mechanisms of action involve mainly κ opioid receptors and N-methyl-d-aspartic acid and γ-aminobutyric acid receptors. Nitrous oxide poisonings have always been rare in the practice of forensic medicine. In addition to accidental overdoses from incorrect administration of anesthesia to a patient in a hospital, toxic effects may occur following the process of chronic abuse, which results in vitamin B12 inactivation, which causes disorders of the nervous system. Sudden death due to nitrous oxide intoxication is a result of hypoxia, which in histopathologic preparations is observed as an acute anoxemic myocardial damage, pulmonary edema, and cerebral edema, with no abnormalities in the kidneys and liver. These changes, however, are not very characteristic and can be typical of many other causes of sudden death, such as sudden asphyxiation, myocardial infarction (heart attack), hemorrhage, or carbon monoxide poisoning. It should be emphasized that in the absence of information about the circumstances of death, the autopsy, routine toxicology tests, and histopathology usually do not indicate a clear cause of death as a result of nitrous oxide abuse.