Effects of nitrous oxide inhalation on brain potentials evoked by auditory and noxious dental stimulation.

1. Effects of inhaling nitrous oxide in oxygen were observed in subjects undergoing noxious dental (N=10) or nonnoxious auditory (N=10) stimulation. Evoked potentials (EPs), 100-500 msec poststimulus, were recorded at vertex, and peak-to-peak amplitudes as well as peak latencies were quantified. 2. Both dental and auditory EPs were reduced by 33% nitrous oxide in oxygen concentration and a dose-related effect was seen in the auditory modality when the concentration was increased to 50%. 3. These observations demonstrate that nitrous oxide inhalation has a broad impact on neurophysiological function in addition to behaviorally determined analgesia.