Hypoxia is common in many chronic lung diseases. Beyond pulmonary considerations, delivery of oxygen (O2)
to the tissues and subsequent O2 utilisation is also determined by other factors including red blood cell mass
and iron status; consequently disruption to these mechanisms provides further physiological strains on an
already stressed system. O2 availability influences ventilation, regulates pulmonary blood flow and impacts
gene expression throughout the body. Deleterious effects of poor tissue oxygenation include decreased
exercise tolerance, increased cardiac strain and pulmonary hypertension in addition to pathophysiological
involvement of multiple other organs resulting in progressive frailty. Increasing inspired O2 is expensive,
disliked by patients and does not normalise tissue oxygenation; thus other strategies that improve O2 delivery
and utilisation may provide a novel therapeutic opportunity in patients with lung disease. In this review, we
focus on the rationale and possibilities for doing this by increasing haemoglobin availability or improving iron
regulation.