For a study, researchers sought to evaluate how well a non-rebreather mask and low-flow nasal cannula (NRB + NC) perform in improving oxygenation in individuals with hypoxemic respiratory failure (HRF) caused by COVID-19 to a high-flow nasal cannula (HFNC).

From June 1 to August 31, 2021, the retrospective investigation was carried out in the emergency rooms of two tertiary hospitals. Patients who required NRB + NC or HFNC and were consecutive >18 years old and admitted for COVID-19-related HRF (defined by World Health Organization criteria as confirmed COVID-19 pneumonia with respiratory rate > 30 breaths/min, severe respiratory distress, or peripheral oxygen saturation <90% on room air) were screened for enrollment. The primary result was an increase in arterial partial pressure of oxygen (PaO2) after two hours. Intubation rate, days without a ventilator, hospital stay duration, and 28-day mortality were considered secondary outcomes. Inverse probability of treatment weighting (IPTW) was used in linear regression to analyze the data based on the propensity score.

About 52 (47.3%) of the 110 patients that were recruited received NRB + NC treatment, whereas 58 (52.7%) received HFNC. Two hours after the start of NRB + NC & HFNC, the patients’ PaO2, PaO2/FIO2 ratio, and respiratory rate were significantly improved. IPTW adjustments were not statistically different between the two groups after PaO2 improvement (adjusted mean ratio [MR] 2.81; 95% CI -5.82 to 11.43; P=.524), intubation rate (adjusted OR 1.76; 95% CI 0.44 to 6.92; P=.423), ventilator-free days (adjusted MR 0.00; 95% CI -8.84 to 8.85; P=.999), hospital length of stay (adjusted MR 3.04; 95% CI -2.62 to 8.69; P=.293), & 28-day mortality (adjusted OR 0.68; 95% CI 0.15 to 2.98; P=.608).

HFNC might be advantageous in COVID-19 HRF. Given the similar improvement in oxygenation at 2 hours and the lack of significant differences in long-term outcomes, NRB + NC is a competitive alternative, particularly in resource-constrained settings. A powered randomized controlled trial must be conducted to examine the efficacy of NRB + NC.