Long-term effects of oxygen-enriched high-flow nasal cannula treatment in COPD patients with chronic hypoxemic respiratory failure

Abstract

Background

This study investigated the long-term effects of humidified high-flow nasal cannula (HFNC) in COPD patients with chronic hypoxemic respiratory failure treated with long-term oxygen therapy (LTOT).

Patients and methods

A total of 200 patients were randomized into usual care ± HFNC. At inclusion, acute exacerbation of COPD (AECOPD) and hospital admissions 1 year before inclusion, modified Medical Research Council (mMRC) score, St George’s Respiratory Questionnaire (SGRQ), forced expiratory volume in 1 second (FEV₁), 6-minute walk test (6MWT) and arterial carbon dioxide (PaCO₂) were recorded. Patients completed phone interviews at 1, 3 and 9 months assessing mMRC score and AECOPD since the last contact. At on-site visits (6 and 12 months), mMRC, number of AECOPD since last contact and SGRQ were registered and FEV₁, FEV₁%, PaCO₂ and, at 12 months, 6MWT were reassessed. Hospital admissions during the study period were obtained from hospital records. Hours of the use of HFNC were retrieved from the high-flow device.

Results

The average daily use of HFNC was 6 hours/day. The HFNC group had a lower AECOPD rate (3.12 versus 4.95/patient/year, p<0.001). Modeled hospital admission rates were 0.79 versus 1.39/patient/year for 12- versus 1-month use of HFNC, respectively (p<0.001). The HFNC group had improved mMRC scores from 3 months onward (p<0.001) and improved SGRQ at 6 and 12 months (p=0.002, p=0.033) and PaCO₂ (p=0.005) and 6MWT (p=0.005) at 12 months. There was no difference in all-cause mortality.

Conclusion

HFNC treatment reduced AECOPD, hospital admissions and symptoms in COPD patients with hypoxic failure.

Keywords:

• COPD
• high-flow heated and humidified oxygen
• HFNC
• exacerbation
• AECOPD
• modified Medical Research Council score
• mMRC score
• 6-minute walk test
• 6MWT

Acknowledgments

We thank Jens Kure, Sales Manager at Home Care, Linde Healthcare, Denmark, and employees for technical support and supportive care of our study population. Fisher & Paykel Healthcare delivered the AIRVO HFNC devices and contributed to the funding of this study, as did the North Jutland Region, Denmark. Data are exclusively authors’ property.

Author contributions

Line Hust Storgaard participated in conception and design, data collection and drafting the manuscript for important intellectual content. Hans-Ulrich Hockey participated in conception and design, analysis and interpretation and drafting the manuscript for important intellectual content. Birgitte Schantz Laursen participated in conception and design and drafting the manuscript for important intellectual content. Ulla Møller Weinreich participated in conception and design, data collection, analysis and interpretation and drafting the manuscript for important intellectual content. All authors contributed toward data analysis, drafting and revising the paper and agree to be accountable for all aspects of the work.

Disclosure

Hans-Ulrich Hockey received remuneration from Fisher & Paykel, who also contributed equipment and some administration costs. The authors report no other conflicts of interest in this work.