Table 2.
Respiratory and cardiac frequency ranges were determined from physiological EtCO2 and SpO2 signals
| Minimum | Peak | Maximum | ||
|---|---|---|---|---|
| Respiratory EtCO2 (Hz) | ||||
| Eyes open | n = 14 | 0.17 ± 0.06 | 0.27 ± 0.06 | 0.35 ± 0.05 |
| Eyes closed | n = 13 | 0.13 ± 0.06 | 0.24 ± 0.06 | 0.32 ± 0.05 |
| Sleep scan 1 | n = 14 | 0.17 ± 0.05 | 0.24 ± 0.04* | 0.31 ± 0.05 |
| Sleep scan 2 | n = 12 | 0.16 ± 0.05 | 0.24 ± 0.05* | 0.32 ± 0.06 |
| Cardiac SpO2 (Hz) | ||||
| Eyes open | n = 14 | 0.96 ± 0.10 | 1.07 ± 0.12 | 1.19 ± 0.16 |
| Eyes closed | n = 13 | 0.90 ± 0.12 | 1.03 ± 0.13*** | 1.19 ± 0.18 |
| Sleep scan 1 | n = 14 | 0.81 ± 0.13 | 0.94 ± 0.16** | 1.09 ± 0.17 |
| Sleep scan 2 | n = 11 | 0.82 ± 0.12 | 0.94 ± 0.16 | 1.11 ± 0.21 |
Individually determined minimum and maximum values for lower and upper edge of the power peak were used for further analysis. Respiratory rate and heart rate decreased in NREM sleep versus awake based on the power peaking value. The n values represent the number of a total of 15 subjects with an available end-tidal carbon dioxide (EtCO2) and fingertip peripheral (SpO2) signals.
*p < 0.05;
**p < 0.01;
***p < 0.001.