Assessment of mask use on oxygen saturation in adults and children with asthma

Background: Mask use is recommended to reduce the transmission of severe acute respiratory syndrome coronavirus 2. The safety of mask use in adults and children with asthma is unknown. Objective: The objective of this study is to evaluate the effect of mask use on peripheral oxygen saturation (SpO₂) in those with and those without asthma. Methods: A two-stage cross-sectional study was performed. In the first stage, the SpO₂ concentration in adults and children with and without asthma was measured with the adults and children at rest during mask use. In the second stage, children years 6-17 performed a 6-minute walk test while wearing masks. The SpO₂ concentration was measured before the exercise and at 3 and 6 minutes into exercise. Subjective dyspnea was evaluated by using the Pediatric Dyspnea Scale (PDS). Results: In the first stage, SpO₂ levels in 393 subjects were analyzed. In the second stage, 50 pediatric subjects were included, 25 with and 25 without asthma. There was no difference in SpO₂ levels between those with and those without asthma in adults and children wearing masks while at rest, with median SpO₂ 98% in both groups. There was no difference in oxygen saturation or reported level of dyspnea between the children with asthma and children without asthma performing the 6-minute walk test while wearing masks. Median SpO₂ levels were at or near 99% in the asthma and non-asthma groups at all time points. Median PDS scores were similar between the asthma and non-asthma groups. Conclusion: Mask use did not affect SpO₂ in adults and children at rest or in children performing low-to-moderate intensity exercise. These findings were consistent in those with and without asthma.