Blood gases, cardiac frequency(fC), blood pressure, dyspnoea and walking distance before and after the 6-min walking test (6MWT).
| Supplemental oxygen | NPPV and supplemental oxygen | Difference after 6MWT 95% CI | p-value | |
| Before 6MWT | ||||
| Pa,O2 mmHg | 72.4±5.6 | 70.7±8.1 | 0.16 | |
| Pa,CO2 mmHg | 50.4±5.7 | 50.1±7.4 | 0.64 | |
| Sa,O2 % | 95.1±1.6 | 94.7±2.1 | 0.524 | |
| pH | 7.40±0.02 | 7.40±0.03 | 0.33 | |
| fC | 89.5±12.2 | 87.6±15.7 | 0.67 | |
| SBP mmHg | 119.5±20.3 | 122.6±17.2 | 0.49 | |
| DBP mmHg | 69.8±14.4 | 70.4±12.6 | 0.85 | |
| BDS | 0 (0/0) | 0 (0/0) | 0.63 | |
| After 6MWT | ||||
| Pa,O2 mmHg | 61.6±7.9 | 81.2±12.4 | 13.3–26.0 | <0.001 |
| Pa,CO2 mmHg | 53.3±6.5 | 51.5±6.4 | -3.5– -0.1 | 0.038 |
| Sa,O2 % | 88.8±4.0 | 94.6±3.4 | 3.7–7.9 | <0.001 |
| pH | 7.37±0.03 | 7.38±0.03 | NF | 0.21 |
| fC | 102.7±14.8 | 101.5±13.3 | -10.0–7.7 | 0.79 |
| SBP mmHg | 133.7±24.2 | 137.5±19.0 | -6.3–13.9 | 0.44 |
| DBP mmHg | 75.3±15.1 | 80.6±12.1 | NF | 0.034 |
| BDS | 6 (4.5–10) | 4 (1.5–4.5) | <0.001 | |
| 6MWD m | 222.0±84.8 | 260.7±64.9 | NF | 0.027 |
Data are presented as mean±sd or median (interquartile range), unless otherwise stated. NPPV: noninvasive positive-pressure ventilation; CI: confidence interval; Pa,O2: arterial oxygen tension; Pa,CO2: arterial carbon dioxide tension; Sa,O2: oxygen saturation; SBP: systolic blood pressure; DBP: diastolic blood presure; BDS: Borg dyspnoea scale; 6MWD: 6-min walking distance; NF: normality test failed. 1 mmHg = 0.133 kPa.