Table 3.

Resting arterial blood gases in COPD subjects

	Absolute	Normal Range
Po2, mmHg	69.9 ± 1.8	80–100
Pco2, mmHg	41.8 ± 2.5	35–45
pH	7.427 ± 0.021	7.34–7.44
SpO2, %	92.3 ± 1.0	>95
tHb, g/dl	16.2 ± 0.1	13–16
O2 content, ml O2/dl	17.9 ± 1.2	15–22
HCO3−, mmol/l	27.0 ± 0.9	22–26

Absolute values represent means ± SE. tHb, total Hb.