title: Does inert gas narcosis have an influence on perception of pain?
abstract: The effect of an increased nitrogen partial pressure under hyperbaric conditions is known as nitrogen narcosis (NN). At an ambient pressure of about 4 bar, reduced cognitive performance as well as euphoric effects are reported. We examined the effect of NN on pain perception. 22 subjects completed an experimental (50 meters = 6 bar) and a simulated control dive (0 m = 1 bar) in a hyperbaric chamber. Before and during each dive a standardized cold pressure test was performed. The intensity of pain perceived was assessed with the help of a visual analogue scale; additionally, subjects assessed the subjective effect of NN. The study showed that the perceived pain intensity is significantly reduced under nitrogen narcosis conditions (F1.21 = 5.167, p < 0.034) when compared to the perceived pain intensity under the control dive conditions (F1.21 = 0.836, p = 0.371). A connection between perceived pain intensity and subjects experience of the NN was not found under the experimental dive condition (r = 0.287, p = 0.195). We could show that even relatively moderate hyperbaric conditions may have an influence on the perception of pain. The results are highly relevant since nitrogen narcosis occurs in divers as well as in medical personnel or construction workers, working under hyperbaric conditions.
authors.affiliation: German Armed Forces Hospital, Research Center of Psychotraumatology, Berlin, Germany. jenskowalski@bundeswehr.org
authors.forename: Jens T
authors.initials: JT
authors.lastname: Kowalski
authors.forename: Saskia
authors.initials: S
authors.lastname: Seidack
authors.forename: Florentin
authors.initials: F
authors.lastname: Klein
authors.forename: Alexander
authors.initials: A
authors.lastname: Varn
authors.forename: Stefan
authors.initials: S
authors.lastname: Röttger
authors.forename: Wateru
authors.initials: W
authors.lastname: Kähler
authors.forename: Wolf Dieter
authors.initials: WD
authors.lastname: Gerber
authors.forename: Andreas
authors.initials: A
authors.lastname: Koch
mesh_terms: D000328:Adult; D001273:Atmosphere Exposure Chambers; D003080:Cold Temperature; D004242:Diving / Q000502:physiology; D005260:Female; D005858:Germany; D006801:Humans; D007222:Inert Gas Narcosis / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement / Q000379:methods*; D058748:Pain Perception / Q000502:physiology*; D055815:Young Adult