The effect of high concentration oxygen therapy on PaCO2 in acute and chronic respiratory disorders.

There is evidence that the potential for high concentration oxygen therapy to increase PaCO2 is not limited to stable and acute exacerbations of COPD, but also to other acute respiratory disorders with abnormal gas exchange such as asthma and pneumonia, and chronic respiratory conditions with hypercapnia such as obesity hypoventilation syndrome. This evidence forms the basis of consensus guidelines which recommend that oxygen therapy is titrated in COPD and other respiratory conditions, to ensure the maximal benefits of oxygen therapy are achieved while reducing the potential for harm due to hyperoxia.