High-flow nasal cannula versus conventional oxygen therapy in acute COPD exacerbation with mild hypercapnia: a multicenter randomized controlled trial

Abstract

Background High-flow nasal cannula (HFNC) can improve ventilatory function in patients with acute COPD exacerbation. However, its effect on clinical outcomes remains uncertain. Methods This randomized controlled trial was conducted from July 2017 to December 2020 in 16 tertiary hospitals in China. Patients with acute COPD exacerbation with mild hypercapnia (pH ≥ 7.35 and arterial partial pressure of carbon dioxide > 45 mmHg) were randomly assigned to either HFNC or conventional oxygen therapy. The primary outcome was the proportion of patients who met the criteria for intubation during hospitalization. Secondary outcomes included treatment failure (intolerance and need for non-invasive or invasive ventilation), length of hospital stay, hospital cost, mortality, and readmission at day 90. Results Among 337 randomized patients (median age, 70.0 years; 280 men [83.1%]; median pH 7.399; arterial partial pressure of carbon dioxide 51 mmHg), 330 completed the trial. 4/158 patients on HFNC and 1/172 patient on conventional oxygen therapy met the criteria for intubation (P = 0.198). Patients progressed to NPPV in both groups were comparable (15 [9.5%] in the HFNC group vs. 22 [12.8%] in the conventional oxygen therapy group; P = 0.343). Compared with conventional oxygen therapy, HFNC yielded a significantly longer median length of hospital stay (9.0 [interquartile range, 7.0–13.0] vs. 8.0 [interquartile range, 7.0–11.0] days) and a higher median hospital cost (approximately $2298 [interquartile range, $1613–$3782] vs. $2005 [interquartile range, $1439–$2968]). There were no significant differences in other secondary outcomes between groups. Conclusions In this multi-center randomized controlled study, HFNC compared to conventional oxygen therapy did not reduce need for intubation among acute COPD exacerbation patients with mild hypercapnia. The future studies should focus on patients with acute COPD exacerbation with respiratory acidosis (pH < 7.35). However, because the primary outcome rate was well below expected, the study was underpowered to show a meaningful difference between the two treatment groups. Trial registration: NCT03003559. Registered on December 28, 2016.

Global Initiative for Chronic Obstructive Lung Disease 2023 Report: GOLD Executive Summary

“…High-flow nasal therapy (HFNT) delivers heated and humidified air-oxygen blends via special devices at rates up to 8 L/min in infants and up to 60 L/min in adults (141). HFNT has been associated with decreased respiratory rate and effort, improved lung mechanics and gas exchange, prolonged time to next exacerbation and improved health-related quality of life scores in COPD patients with acute (or chronic) hypercapnia (142)(143)(144), but did not prevent intubation in hospitalized patients with ECOPD (145). In fact, the European Respiratory Society (ERS) recommends ventilatory support before using HFNT in hypercapnic ECOPD (146).…”

Global Initiative for Chronic Obstructive Lung Disease 2023 Report: GOLD Executive Summary

“…High-flow nasal therapy (HFNT) delivers heated and humidified air-oxygen blends via special devices at rates up to 8 L/min in infants and up to 60 L/min in adults (141). HFNT has been associated with decreased respiratory rate and effort, improved lung mechanics and gas exchange, prolonged time to next exacerbation and improved healthrelated quality of life scores in COPD patients with acute (or chronic) hypercapnia (142)(143)(144), but did not prevent intubation in hospitalized patients with ECOPD (145). In fact, the European Respiratory Society (ERS) recommends ventilatory support before using HFNT in hypercapnic ECOPD (146).…”

High‑flow nasal cannula is not more effective than conventional oxygen therapy for acute exacerbation of COPD with mild hypercapnia: we are not sure

“…We read with great interest the article published in Critical Care by Xia et al entitled “High-flow nasal cannula versus conventional oxygen therapy in acute COPD exacerbation with mild hypercapnia: a multicenter randomized controlled trial” [ 1 ]. In this randomized controlled trial, the authors aimed to compare conventional oxygen therapy (COT) and high-flow nasal cannula (HFNC) in hospitalized patients with acute exacerbations of chronic obstructive pulmonary disease (COPD) and mild hypercapnia (pH ≥ 7.35, PaCO 2 > 45 mmHg).…”