Abstract
BACKGROUND: During the COVID-19 pandemic, managing respiratory failure in critically ill patients has presented significant challenges. A high-flow nasal cannula (HFNC) has been established as an effective respiratory support modality, offering heated, humidified oxygen at high flow rates. However, concerns persist regarding the potential for aerosol dispersion and the risk of viral transmission, particularly in COVID-19. This study investigates the impact of surgical mask (3-ply surgical mask) placement over HFNC on oxygenation parameters in COVID-19 patients experiencing hypoxemic respiratory failure. METHODS: A retrospective analysis of clinical data from a tertiary medical facility was conducted. The study included 35 patients with confirmed COVID-19 and moderate to severe hypoxemia. Oxygenation indices such as the SpO(2)/FiO(2) (SF) ratio, flow rate, and the ratio of oxygen saturation index (ROX index) were monitored before and after the application of surgical masks over HFNC. Statistical analyses were performed to compare these parameters before and after surgical mask placement. RESULTS: The adjunctive use of surgical masks over HFNC significantly improved oxygenation parameters compared to HFNC alone. Despite these improvements, there was no significant change in heart and respiratory rates, quick sequential organ failure assessment (qSOFA) scores, or Glasgow Coma Scale (GCS) levels. Subgroup analysis showed an increase in SF ratio ranging between 5.49% and 6.04% in patients with ROX indices, but these trends were not statistically significant. CONCLUSION: This study provides preliminary evidence that surgical masks over HFNC may enhance oxygenation in critically ill COVID-19 patients with hypoxemic respiratory failure. These results underscore the potential importance of infection control measures in respiratory therapy during pandemics and suggest that further investigation in more extensive prospective studies is warranted.