Changes in the pattern reversal visual evoked potential as a function of inspired nitrous oxide concentration.
The VEP to pattern displacement was measured at different levels of inspired N2O concentrations in air in 10 normal subjects. The inspired concentrations were 10, 20, 30 and 40% N2O. Expired CO2 concentrations were also measured. Ten normal controls went through the same procedure but breathed air on each trial rather than N2O. The results showed a significant decrease at 10%, almost at 20% and again significant at 30% and 40% for the amplitude of the N65-P95 wave. The P95-N125 wave was more resistant--10% was not significant, 20% was again nearly significant and 30% and 40% were significant. There were no latency changes. Because of the wider variance between group comparisons there was a significant reduction at 40% only for the N65-P95 wave and no significant difference for the P95-N125 wave. There was some evidence that the amplitude of the early components was still significantly reduced after the end of the experiment.
D000328:Adult; D001921:Brain / Q000502:physiology; D004569:Electroencephalography; D005074:Evoked Potentials, Visual / Q000187:drug effects*; D006801:Humans; D008297:Male; D009609:Nitrous Oxide / Q000494:pharmacology*; D010100:Oxygen / Q000494:pharmacology
D009609:Nitrous Oxide; D010100:Oxygen