• COPD Exacerbations
• Long Term Oxygen Therapy (LTOT)
• Idiopathic pulmonary fibrosis

On a rather cold summer afternoon 45 years ago, I found myself, a humble research fellow, in a committee room in the University of Birmingham UK surrounded by famous professors and investigators of hypoxaemic lung disease. My chief, the late Professor David Flenley, had been asked by the British Council to lecture in China and had sent me to deputise for him on the writing committee of the Medical Research Council (MRC) trial of domiciliary oxygen therapy in what we now call chronic obstructive pulmonary disease (COPD). The paper we wrote (in which the authors kindly acknowledged my role) has had significant consequences for hundreds of thousands of patients in the 44 years since its publication.1 Ours remains the only randomised placebo-controlled study of home oxygen therapy in COPD as the US Nocturnal Oxygen Therapy Trial (NOTT) compared 12 with 24 hours (in practice 17 hours) of therapy.2 The MRC study was arduous for both patients and investigators with regular arterial gas monitoring, cardiac catheterisation and exercise testing. Only 89 patients were recruited compared with 203 in the USA. However, even with this modest number of patients, there was a clear reduction in mortality with oxygen therapy and a stabilisation of the pulmonary artery pressure, the presumed mechanism …