Table 1.
Background characteristics of enrolled subjects with COPD.
| Hypercapnia | Normocapnia | p Value | |
|---|---|---|---|
| (n = 22) | (n = 102) | ||
| Age, years-old | 76.5 (68.25–80.75) | 73 (67.25–77.75) | 0.245 |
| Gender, male/female, n | 9/13 | 74/28 | 0.303 |
| Smoking history, pack-years | 55 (32.5–105.12) | 54 (39–91.87) | 0.816 |
| Hight, cm | 157.35 (151.72–168) | 161 (154.37–167.22) | 0.786 |
| Body weight, kg | 52.85 (48.17–67.25) | 57.9 (50.15–68.8) | 0.252 |
| BMI, kg/m2 | 20.88 (18.66–25.60) | 23.36 (20.11–25.74) | 0.18 |
| Body surface area, m2/kg2 | 1.53 (1.45–1.69) | 1.58 (1.47–1.75) | 0.308 |
| Arterial blood gas | |||
| pH | 7.42 (7.39–7.42) | 7.44 (7.43–7.46) | <0.001 |
| pCO2, mmHg | 46.60 (45.7–53.2) | 36.55 (35–39.7) | <0.001 |
| pO2, mmHg | 71.2 (67.8–84.52) | 84.55 (75.62–90.45) | <0.003 |
| HCO3-, mmol/L | 30 (27.97–32.52) | 24.9 (23.32–26.37) | <0.001 |
| BE, mmol/L | 4.1 (2.95–7.5) | 0.9 (−0.3–2.2) | <0.001 |
| tCO2, mmHg | 26 (24–27.7) | 30.75 (29.2–33.82) | <0.001 |