Nitrogen Narcosis - History

History

French researcher Victor T. Junod was the first to describe symptoms of narcosis in 1834, noting "the functions of the brain are activated, imagination is lively, thoughts have a peculiar charm and, in some persons, symptoms of intoxication are present." Junod suggested that narcosis resulted from pressure causing increased blood flow and hence stimulating nerve centers. Walter Moxon (1836–1886), a prominent Victorian physician, hypothesized in 1881 that pressure forced blood to inaccessible parts of the body and the stagnant blood then resulted in emotional changes. The first report of anesthetic potency being related to lipid solubility was published by Hans H. Meyer in 1899, entitled Zur Theorie der Alkoholnarkose. Two years later a similar theory was published independently by Charles Ernest Overton. What became known as the Meyer-Overton Hypothesis is illustrated in the diagram to the right.

In 1939, Albert R. Behnke and O. D. Yarborough demonstrated that gases other than nitrogen also could cause narcosis. For an inert gas the narcotic potency was found to be proportional to its lipid solubility. As hydrogen has only 0.55 the solubility of nitrogen, deep diving experiments using hydrox were conducted by Arne Zetterström between 1943 and 1945. Jacques-Yves Cousteau in 1953 famously described it as "l’ivresse des grandes profondeurs" or the "rapture of the deep".

Further research into the possible mechanisms of narcosis by anesthetic action led to the "minimum alveolar concentration" concept in 1965. This measures the relative concentration of different gases required to prevent motor response in 50% of subjects in response to stimulus, and shows similar results for anesthetic potency as the measurements of lipid solubility. The (NOAA) Diving Manual was revised to recommend treating oxygen as if it were as narcotic as nitrogen, following research by Christian J. Lambertsen et al. in 1977 and 1978.