Table 2.
Arterial blood gas and acid-base status.
| Arterial blood draws | |||||||
|---|---|---|---|---|---|---|---|
| 1045/1400 m |
3440 m |
3820 m |
4240 m |
||||
| Baseline | P-value | P-value | P-value | ||||
| PaO2 (mmHg) | 84.80 ± 5.35 | 48.56 ± 8.08∗ | P < 0.001 | 54.56 ± 6.23∗ | P < 0.001 | 48.38 ± 4.96∗ | P < 0.001 |
| SaO2 (%) | 96.80 ± 0.79 | 84.89 ± 7.87∗ | P = 0.032 | 88.78 ± 3.73∗ | P = 0.003 | 85.50 ± 3.66∗ | P < 0.001 |
| PaCO2 (mmHg) | 34.84 ± 4.58 | 30.23 ± 4.93∗ | P = 0.015 | 29.57 ± 3.76∗ | P = 0.016 | 29.05 ± 3.73∗ | P = 0.001 |
| Bicarbonate (mmol/L) | 23.24 ± 2.69 | 20.99 ± 3.08 | P = 0.417 | 19.48 ± 2.01∗ | P = 0.043 | 19.69 ± 2.80∗† | P = 0.021 |
| Base excess (mmol/L) | –1.20 ± 2.78 | –3.00 ± 3.08 | P = 1.000 | –4.78 ± 1.86 | P = 0.077 | –4.50 ± 3.07† | P = 1.000 |
| pH | 7.43 ± 0.02 | 7.45 ± 0.02 | P = 0.879 | 7.43 ± 0.02† | P = 1.000 | 7.44 ± 0.02 | P = 1.000 |
Changes in arterial blood values with ascent. The exact p-value comparing each altitude to baseline is provided. ∗ = denotes statistical significance from 1045/1400 m. † = Statistical significance from 3440 m. Presented as mean ± SD.