Table 2.

Central and carotid chemoreceptor reflex responses

	Control	COPD
Transient hyperoxia
Baseline ${\dot{V}}_{\mathrm{E}}$ (L min−1)	7.88 ± 0.51	8.41 ± 0.83
Nadir (15 s) ${\dot{V}}_{\mathrm{E}}$ (L min−1)	7.76 ± 0.61	6.16 ± 0.61
Nadir (15 s) change in ${\dot{V}}_{\mathrm{E}}$ from baseline (L min−1)	0.12 ± 0.46	2.25 ± 0.59*
Hyperoxic hypercapnic ventilatory response
Δ${\dot{V}}_{\mathrm{E}}$/Δ$P_{\mathrm{ETC}{\mathrm{O}}_2}$ slope (L min−1 mmHg−1)	1.22 ± 0.27	0.93 ± 0.18
Hypoxic ventilatory response
Δ${\dot{V}}_{\mathrm{E}}$/ΔS pO 2 slope (L min−1 %−1)	0.04 ± 0.03	0.23 ± 0.08*

Data are presented as means ± SEM. $P_{\mathrm{ETC}{\mathrm{O}}_2}$: partial pressure of carbon dioxide; S _{pO 2}: oxygen saturation measured by pulse oximeter; ${\dot{V}}_{\mathrm{E}}$: minute ventilation. ^* P < 0.05 between groups