Table 2

Spirometric and arterial blood gas measurements

Eucapnic (n=83)Hypercapnic (n=162)
FEV1 (L)2.48±0.981.55±0.84*
FVC (L)2.92±1.121.84±0.97*
FEV1% predicted77.6±23.158.5±44.6*
FVC % predicted74.7±21.856.9±36.6*
PaO2 (kPa)9.86±1.498.15±1.36*
PaCO2 (kPa)5.43±0.387.19±0.9*
HCO3 (mmol/L1)25.5±1.931.8±3.6*
Base excess1.0±1.75.96±4.17*
Haematocrit (%)44.0±5.044.4±8.7
  • Values expressed as mean±SD.

  • *Significant difference compared with eucapnic group (p<0.001).

  • FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity; HCO3, arterial bicarbonate ion concentration; PaCO2, arterial partial pressure of carbon dioxide; PaO2, arterial partial pressure of oxygen.