Rationale: A growing evidence base suggests a benefit of using high-flow nasal cannula oxygen therapy in the acute setting. However, the clinical benefit of domiciliary use of high-flow nasal cannula oxygen therapy in patients with chronic hypercapnic respiratory failure due to chronic obstructive pulmonary disease remains unclear.
Objectives: To evaluate the efficacy and safety of high-flow nasal cannula oxygen therapy use in patients with stable chronic obstructive pulmonary disease.
Methods: We conducted a multicenter, randomized crossover trial comparing high-flow nasal cannula oxygen therapy plus long-term oxygen therapy with long-term oxygen therapy only in 32 adults with stable hypercapnic chronic obstructive pulmonary disease. Participants were randomized to receive either 6 weeks of high-flow nasal cannula oxygen therapy/long-term oxygen therapy using the myAIRVO 2 device followed by another 6 weeks of long-term oxygen therapy only or long-term oxygen therapy only followed by high-flow nasal cannula oxygen therapy/long-term oxygen therapy. The primary outcome was the change in quality of life as assessed by St. George's Respiratory Questionnaire for chronic obstructive pulmonary disease. A linear mixed-effects model was used to account for treatment effect, time effect, allocation effect, and participant effect.
Results: Of 32 study participants, 29 completed the study. At the end of 12 weeks, high-flow nasal cannula oxygen therapy/long-term oxygen therapy treatment improved the mean total St. George's Respiratory Questionnaire for chronic obstructive pulmonary disease score compared with long-term oxygen therapy only (7.8 points; 95% confidence interval, 3.7 to 11.9; P < 0.01). Similarly, high-flow nasal cannula oxygen therapy/long-term oxygen therapy treatment improved the arterial partial pressure of carbon dioxide (adjusted treatment effect, -4.1 mm Hg; 95% confidence interval, -6.5 to -1.7 mm Hg), pH (adjusted treatment effect, +0.02; 95% confidence interval, 0.01 to 0.02), and median nocturnal transcutaneous carbon dioxide pressure (adjusted treatment effect, -5.1 mm Hg; 95% confidence interval, -8.4 to -1.8 mm Hg). High-flow nasal cannula oxygen therapy/long-term oxygen therapy treatment did not improve the arterial partial pressure of oxygen, dyspnea, spirometry, lung volume, 6-minute walk test, or physical activity. The most frequent high-flow nasal cannula oxygen therapy-related adverse event encountered was nocturnal sweating (n = 6 [20.7%]). Four severe adverse events occurred (two in each group) and were deemed unrelated to the intervention.
Conclusions: Six weeks of treatment with high-flow nasal cannula oxygen therapy improved health-related quality of life and reduced hypercapnia in patients with stable hypercapnic chronic obstructive pulmonary disease. Clinical trial registered with www.clinicaltrials.gov (NCT02545855) and www.umin/ac.jp (UMIN000017639).
Keywords: crossover studies; home care service; oxygen inhalation therapy; quality of life.