RT Journal Article
SR Electronic
T1 In COPD, Nocturnal Noninvasive Ventilation Reduces the F<sub>IO<sub>2</sub></sub> Delivered Compared With Long-Term Oxygen Therapy at the Same Flow
JF Respiratory Care
FD American Association for Respiratory Care
SP 1897
OP 1903
DO 10.4187/respcare.07570
VO 65
IS 12
A1 Michael Cardinale
A1 Pierre-Julien Cungi
A1 Pierre Esnault
A1 Olivier Castagna
A1 Cédric Nguyen
A1 Erwan Daranda
A1 Julien Bordes
A1 Jean-Michel Arnal
A1 Eric Meaudre
A1 Philippe Goutorbe
YR 2020
UL http://rc.rcjournal.com/content/65/12/1897.abstract
AB BACKGROUND: Nocturnal noninvasive ventilation is recommended for patients with hypercapnic COPD. Long-term oxygen therapy improves survival in patients with hypoxemic disease. However, leaks during noninvasive ventilation are likely to reduce the fraction of inspired oxygen.OBJECTIVES: To compare nocturnal inspired O2 fractions during noninvasive ventilation with daytime pharyngeal inspired O2 fractions during nasal cannula oxygen therapy (with the same O2 flow) in patients with COPD at home (ie, real-life conditions).METHODS: This single-center prospective observational study included 14 subjects with COPD who received long-term O2 therapy. We analyzed pharyngeal inspired O2 fractions in the evening, with a nasopharyngeal probe (sidestream gas analyzer). The O2 flow was measured with a precision flow meter, at the usual flow. Then, the same O2 flow was implemented for noninvasive ventilation with a study’s home ventilator. The all-night noninvasive ventilation parameters were delivered in pressure mode with a single-limb leaking circuit. Daytime and nighttime inspired O2 fractions were compared.RESULTS: The mean ± SD daytime pharyngeal inspired O2 fraction, measured with normobaric basal O2 flow, 0.308 ± 0.026%, was significantly higher than the mean ± SD nighttime inspired O2 fraction, measured during noninvasive ventilation (0.251 ± 0.011; P &lt; .001).CONCLUSIONS: The nighttime inspired O2 fraction decreased with a modern noninvasive ventilation pattern, pressure target, and intentional leaks. This partial lack of O2 therapy is likely to be harmful. It might explain the poor results in all but 2 randomized controlled trials on long-term noninvasive ventilation in COPD. (ClinicalTrials.gov registration NCT02599246.)