Table 3.
Steady‐state ventilatory responses
| Normoxia | Hypoxia | Δ | Delta (%) | |
|---|---|---|---|---|
| Respiratory rate (breaths·min−1) | ||||
| Saline | 14 ± 1 | 14 ± 1 | 0 ± 0 | −1 ± 2 |
| Dopamine | 13 ± 1 | 14 ± 1 | 1 ± 1 | 7 ± 4 |
| Tidal volume (mL) | ||||
| Saline | 559 ± 62 | 814 ± 61* | 256 ± 27 | 54 ± 8 |
| Dopamine | 530 ± 42 | 727 ± 54* | 197 ± 30 | 40 ± 6 |
| Minute ventilation (L·min−1) | ||||
| Saline | 7.8 ± 0.8 | 11.3 ± 0.8* | 3.4 ± 0.4 | 51 ± 8 |
| Dopamine | 6.8 ± 0.4 | 10.0 ± 0.7* | 3.2 ± 0.5 | 49 ± 8 |
| Inspiratory time (sec) | ||||
| Saline | 2.3 ± 0.2 | 2.1 ± 0.2* | −0.2 ± 0.1 | −10 ± 5 |
| Dopamine | 2.6 ± 0.2 | 2.3 ± 0.3 | −0.3 ± 0.2 | −11 ± 7 |
| End‐tidal CO2 (mmHg) | ||||
| Saline | 41 ± 1 | 37 ± 1* | −4 ± 1 | −10 ± 1 |
| Dopamine | 44 ± 1 | 40 ± 1* | −4 ± 1 | −9 ± 1 |
| Inspired O2 (%) | ||||
| Saline | 21 | 13.9 ± 0.3* | −8.1 ± 0.3 | −37 ± 1 |
| Dopamine | 21 | 15.1 ± 0.4* | −6.6 ± 0.3† | −30 ± 2† |
| SpO2 (%) | ||||
| Saline | 99 ± 0 | 84 ± 1* | −14 ± 1 | −14 ± 1 |
| Dopamine | 98 ± 0 | 84 ± 1* | −14 ± 1 | −14 ± 1 |
Data are reported as mean ± SEM from n = 15 unless otherwise noted (inspiratory time, n = 13).
*P < 0.05 versus Normoxia, † P < 0.05 versus Saline.