Table 1.
Summary of hypercapnia paradigm parameter values derived from pulse oximetry, capnography, and iTRUST MRI in 10 subjects.
| Parameter | Baseline (0–5 min) | Hypercapnia (7.5–10 min) | Change (%) | P-value |
|---|---|---|---|---|
| EtCO2 | 38.5 (2.9) | 50.1 (2.1) | 30.5 (5.5) | <0.0001 |
| Ya | 97.7 (0.6) | 98.3 (0.7) | 0.6 (0.6) | <0.01 |
| tCBF | 45.7 (6.0) | 70.1 (11.4) | 53.0 (12.7) | <0.0001 |
| Yv-SBO | 66.7 (5.1) | 77.2 (4.8) | 15.9 (2.8) | <0.0001 |
| Yv-T2 | 62.3 (3.1) | 78.4 (3.5) | 25.8 (3.7) | <0.0001 |
| AVO2D-SBO | 31.1 (4.8) | 21.1 (4.4) | − 32.5 (4.7) | <0.0001 |
| AVO2D-T2 | 35.4 (2.9) | 19.9 (3.0) | − 43.8 (5.9) | <0.0001 |
| CMRO2-SBO | 123.4 (18.7) | 127.9 (25.7) | 3.3 (9.7) | 0.31 |
| CMRO2-T2 | 140.4 (9.7) | 120.0 (9.5) | − 14.6 (3.6) | <0.0001 |
Parentheses indicate the standard deviations of parameter values across subjects. P-values are based on one-sample Student's t-tests of the percent changes from baseline to hyper-capnia. AVO2D is the arteriovenous oxygen difference, equal to Ya – Yv.