Table 2.
CPET determinations at rest and peak exercise
| Variable | Resting determinations mean ± SD, n (%) |
Peak exercise determinations mean ± SD, n (%) |
|---|---|---|
| n | 751 | 631 |
| ABG Parameters | ||
| pH | 7.42 ± 0.03 | 7.35 ± 0.05 |
| PaO2 (mmHg) | 87.8 ± 11.4 | 97.9 ± 16.9 |
| PaCO2 (mmHg) | 37.7 ± 4.2 | 34.4 ± 5.9 |
| HCO3 (meq/L) | 24.2 ± 2.2 | 18.7 ± 4.9 |
| SaO2 (%) | 94.4 ± 1.7 | 94.5 ± 2.8 |
| Hemoglobin (g/dL) | 13.9 ± 2.0 | 15.0 ± 4.0 |
| Carboxyhemoglobin (%) | 1.49 ± 0.87 | 1.23 ± 0.77 |
| A-a gradient (mmHg) | 12.8 ± 11.4 | 19.5 ± 4.0 |
| SpO2 − SaO2 (%) | 3.82 ± 2.06 | 2.63 ± 2.75 |
| Spirometry Parameters | ||
| FEV1 (L) | 2.6 ± 0.9 | 2.71 ± 1.05 |
| FEV1 (% of predicted) | 83.8 ± 20.2 | |
| FEV1 % change | −1.9 ± 21.7 | |
| FVC (L) | 3.4 ± 1.1 | 3.40 ± 1.31 |
| FVC (% of predicted) | 86.0 ± 17.9 | |
| FVC % change | −2.2 ± 21.6 | |
| Minute ventilation (L/min) | 11.8 ± 4.1 | 70.0 ± 25.0 |
| CPET Parameters | ||
| Heart rate (bpm) | 82 ± 16 | 141 ± 26 |
| Respiratory rate (rpm) | 17 ± 5 | 42 ± 10 |
| SpO2 (%) | 98.2 ± 1.8 | 97.1 ± 3.2 |
| Oxygen consumption (ml/min) | 319 ± 89 | 1760 ± 632 |
| Oxygen consumption/kg (ml/min/kg) | 3.9 ± 0.9 | 21.6 ± 8.8 |
| Oxygen pulse (ml/min/bpm) | 4.0 ± 1.2 | 12.5 ± 4.0 |
| End tidal CO2 (mmHg) | 33.2 ± 5.0 | 34.3 ± 6.6 |
Abbreviations: ABG = arterial blood gas; BMI = body mass index; CO2 = carbon dioxide; CPET = cardiopulmonary exercise testing; FEV1 = forced expiratory volume in one second; FVC = forced vital capacity; HCO3 = bicarbonate; O2 = oxygen; PaO2 = partial pressure of oxygen; PaCO2 = partial pressure of carbon dioxide; SaO2 = arterial hemoglobin oxygen saturation; SpO2 = pulse oximetry; SD = standard deviation. FEV1 and FVC % change refer to the percent variation post-exercise spirometry when compared to the resting determination.