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

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. 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. 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). 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. 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.