TABLE 3.
Mean and standard deviation of the physiological variables. The mean and standard deviation of inter-scan and inter-block differences are reported, together with the 95% confidence intervals.
| ROI/Block | Scan 1 | Scan 2 | Inter-scan difference (scan 2—scan 1) | |
|---|---|---|---|---|
| BOLD baseline (a.u) | SGM | 340.1 ± 53.1 | 340.4 ± 50.7 | 0.4 ± 34.9 (−13.2, 13.9) |
| CGM | 328.9 ± 53.5 | 328.1 ± 49.2 | −0.9 ± 35.3 (−14.6, 12.8) | |
| GM | 336.4 ± 53.1 | 336.3 ± 49.3 | −0.1 ± 35.3 (−13.8, 13.6) | |
| NAWM | 295.4 ± 43.3 | 296.0 ± 39.9 | 0.6 ± 29.2 (−10.7, 11.9) | |
| EtCO2 baseline (mmHg) | − | 38.0 ± 3.8 | 37.7 ± 3.0 | −0.3 ± 1.3 (−1.1, 0.4) |
| EtCO2 change (mmHg) | − | 12.7 ± 1.6 | 13.6 ± 1.3 | 1.0 ± 1.0 (0.4, 1.5) |
| EtO2 baseline (mmHg) | − | 122.8 ± 5.4 | 122.9 ± 4.2 | 0.1 ± 3.4 (−1.9, 2.1) |
| EtO2 change (mmHg) | − | 14.0 ± 3.1 | 15.6 ± 2.4 | 1.6 ± 2.1 (0.4, 2.8) |
| MAP pre-CVR scan (mmHg) | − | 84.7 ± 7.7 | 85.8 ± 9.4 | 1.14 ± 8.28 (−3.64, 5.93) |
| MAP post-CVR scan (mmHg) | − | 78.6 ± 8.4 | 78.8 ± 9.2 | 0.14 ± 5.32 (−2.93, 3.21) |
| Difference in MAP (post-CVR—pre-CVR) (mmHg) | − | −6.02 ± 5.76 | −7.02 ± 6.58 | −1.00 ± 8.76 (−6.06, 4.06) |
| Heart rate (bpm) | Air | 71.6 ± 13.0 | 65.5 ± 13.7 | −6.1 ± 5.2 (−9.1, −3.1) |
| CO2 | 70.1 ± 13.1 | 65.4 ± 13.6 | −4.6 ± 5.8 (−8.0, −1.3) | |
| All | 70.9 ± 13.0 | 65.5 ± 13.6 | −5.5 ± 5.4 (−8.6, −2.4) | |
| Respiration rate (breaths per minute) | Air | 12.3 ± 3.6 | 12.4 ± 3.6 | 0.1 ± 1.0 (−0.5, 0.6) |
| CO2 | 12.4 ± 3.5 | 12.5 ± 3.5 | 0.1 ± 1.3 (−0.6, 0.9) | |
| All | 12.4 ± 3.5 | 12.4 ± 3.5 | 0.1 ± 1.0 (−0.5, 0.7) | |
| Inter-block difference in heart rate (bpm) (CO2—Air) | − | −1.5 ± 2.3 (−2.8, −0.2) | −0.1 ± 1.9 (−1.2, 1.0) | − |
| Inter-block difference in respiration rate (breaths per minute) (CO2—Air) | − | 0.1 ± 0.9 (−0.4, 0.6) | 0.0 ± 0.9 (−0.5, 0.6) | − |
Abbreviations: ROI, region of interest; BOLD, blood oxygen-level dependent; GM, grey matter; SGM, subcortical GM; CGM, cortical GM; NAWM, normal-appearing white matter; EtCO2, end-tidal carbon dioxide; EtO2, end-tidal oxygen; MAP, mean arterial pressure.