The second gas effect was proposed by Epstein et al.
They described this situation as the supramaximal second gas effect. However, Lin and Wang (21) criticized the supramaximal second gas effect as a non-existent phenomenon; they claimed that the study conducted by Watanabe et al.
Evaluating the second gas effect of [N.sub.2]O by keeping all these parameters constant is difficult.
(14) in which they did not accept the second gas effect, the ventilation parameters were not kept constant, and the cardiac effects of [N.sub.2]O were ignored.
Those who defend that it shortens the induction period have suggested that [N.sub.2]O accomplishes this by the second gas effect and the previously shown additive effects (11,18,19,30).
The results of this study showed that, with the addition of [N.sub.2]O, the sevoflurane induction was accelerated, and the intubation without administering muscle relaxant was facilitated, suggesting that [N.sub.2]O plays a significant role in the process of sevoflurane uptake to the body (second gas effect) in adults, also.
Magnitude of the second gas effect on arterial sevoflurane partial pressure.
Large volume [N.sub.2]O uptake alone does not explain the second gas effect of [N.sub.2]O on sevoflurane during constant inspired ventilation.
An additional explanation for the second gas effect: a concentrating effect.
(14.) Sun XG, Su F, Shi YQ, Lee C The "second gas effect" is not a valid concept.
It was reported that the addition of [N.sub.2]O during induction was beneficial due to the concentration and second gas effects (1-3).