Fig. 6
A–D Summary data show respiratory frequency (A), tidal volume (B), minute ventilation (C), and inspiratory time (Ti)/expiratory time (Te) ratio (D) with 1 MAC sevoflurane, 1 MAC isoflurane, 1 ED50 propofol and 1 ED50 etomidate groups with 100% oxygen. E–H Characteristic tracings of four general anesthetics on respiratory parameters in vivo. I-L Time-course study of 1 MAC sevoflurane (I), 1 MAC isoflurane (J), 1 ED50 propofol (K) and 1 ED50 etomidate (L) on Ti and Te with 100% oxygen in vivo. Data are expressed as mean ± standard deviation. *, #, †indicate that there were significant differences compared with sevoflurane, isoflurane, and propofol groups, respectively, by one-way ANOVA (P < 0.05)