Response

Abstract

To the Editor:We thank Garcia-Talavera and colleagues for their interest in our article published in CHEST (September 2008).1Drummond MB Blackford AL Benditt JO et al.Continuous oxygen use in nonhypoxemic emphysema patients identifies a high-risk subset of patients.Chest. 2008; 134: 497-506Abstract Full Text Full Text PDF PubMed Scopus (39) Google Scholar Our retrospective analysis of the National Emphysema Treatment Trial (NETT) demonstrated that participants with resting normoxia and exercise desaturation had worse disease severity and survival than those without exercise desaturation, despite the use of continuous supplemental oxygen. Garcia-Talavera and colleagues commented that the indication for oxygen therapy was not fully described in our report. Per the NETT protocol, exercise desaturation was determined by a treadmill walking test conducted prior to the 6-min walk test, not by monitoring during the 6-min walk test. The time to desaturation on the treadmill test was collected; however, we did not analyze these data.Importantly, participants in the NETT could receive oxygen prescriptions through rehabilitation centers or their primary care physician, thus making it difficult to collect specific information on the indications for oxygen therapy. In this sense, the NETT mimicked the challenges of monitoring oxygen prescription in the course of routine clinical practice, where oxygen therapy can be initiated by many different health-care providers.Studies such as that performed by Garcia-Talavera and colleagues2Garcia-Talavera I Hernandez Garcia C Casanova C et al.Time to desaturation in the 6-min walking distance test predicts 24-hours oximetry in COPD patients with a Po2 between 60 and 70 mm Hg.Respir Med. 2008; 102: 1026-1032Abstract Full Text Full Text PDF PubMed Scopus (30) Google Scholar will advance our understanding of the role of oxygen therapy in patients who fall outside of established indications. The findings of our analysis emphasize the need for prospective clinical trials to characterize the factors that predict which COPD patients may benefit from supplemental oxygen. From such studies we may eventually refine our current indications for oxygen therapy. To the Editor: We thank Garcia-Talavera and colleagues for their interest in our article published in CHEST (September 2008).1Drummond MB Blackford AL Benditt JO et al.Continuous oxygen use in nonhypoxemic emphysema patients identifies a high-risk subset of patients.Chest. 2008; 134: 497-506Abstract Full Text Full Text PDF PubMed Scopus (39) Google Scholar Our retrospective analysis of the National Emphysema Treatment Trial (NETT) demonstrated that participants with resting normoxia and exercise desaturation had worse disease severity and survival than those without exercise desaturation, despite the use of continuous supplemental oxygen. Garcia-Talavera and colleagues commented that the indication for oxygen therapy was not fully described in our report. Per the NETT protocol, exercise desaturation was determined by a treadmill walking test conducted prior to the 6-min walk test, not by monitoring during the 6-min walk test. The time to desaturation on the treadmill test was collected; however, we did not analyze these data. Importantly, participants in the NETT could receive oxygen prescriptions through rehabilitation centers or their primary care physician, thus making it difficult to collect specific information on the indications for oxygen therapy. In this sense, the NETT mimicked the challenges of monitoring oxygen prescription in the course of routine clinical practice, where oxygen therapy can be initiated by many different health-care providers. Studies such as that performed by Garcia-Talavera and colleagues2Garcia-Talavera I Hernandez Garcia C Casanova C et al.Time to desaturation in the 6-min walking distance test predicts 24-hours oximetry in COPD patients with a Po2 between 60 and 70 mm Hg.Respir Med. 2008; 102: 1026-1032Abstract Full Text Full Text PDF PubMed Scopus (30) Google Scholar will advance our understanding of the role of oxygen therapy in patients who fall outside of established indications. The findings of our analysis emphasize the need for prospective clinical trials to characterize the factors that predict which COPD patients may benefit from supplemental oxygen. From such studies we may eventually refine our current indications for oxygen therapy.