Figure 2From: The effect of high concentration oxygen therapy on PaCO2 in acute and chronic respiratory disorders The change in PtCO 2 (mmHg) from baseline following breathing 100% oxygen or room air in subjects with obesity hypoventilation syndrome. The vertical lines are the mean (central horizontal line) ±1 SD for 20 min PtCO2 minus baseline. Reproduced from reference [20].Back to article page