Sadaka AS, et al. - Researchers sought to determine the clinical significance of exercise response to oxygen supplementation in hypoxemic patients with obstructive lung disease. They examined chronic obstructive lung disease patients at their center. The patients who underwent a 6-minute walking test (6MWT) for ambulatory oxygen assessment and who desaturated breathing air and therefore had an additional walk test on supplemental oxygen were analyzed. Responders were defined as walking ≥26 m further with oxygen. Survival was compared in oxygen responders and nonresponders. They found acute exercise response to supplemental oxygen was not associated with long-term survival in patients with obstructive lung disease. The use of ambulatory oxygen treatment for symptomatic purposes only was supported by findings.