Implications of face mask use on body composition assessment by air-displacement plethysmography.

BACKGROUND & AIMS: The BOD POD (COSMED USA Inc., Concord, CA) is a common instrument used to assess body composition by employing air displacement plethysmography and whole-body densitometry to determine body volume. This instrument requires isothermal conditions during testing; therefore, the introduction of outside isothermal air can impact testing results. With the COVID-19 pandemic introducing face mask mandates, it is unknown whether the use of a face mask during BOD POD testing may lead to erroneous measurement by introducing isothermal air. Thus, the purpose of this cross-sectional study was to investigate the impact of wearing a surgical face mask compared to not wearing a surgical face mask on body composition assessment among adults. METHODS: During testing, female subjects were required to wear a swimsuit or form-fitting lycra shorts and a sports bra and male subjects were required to wear form-fitting lycra shorts. American Society for Testing and Materials (ASTM) level one surgical face masks (bacterial and particulate filtration efficiency of 95%) and standard swim caps were provided by researchers. Variables of interest included percent body fat, body fat, percent lean body mass, and lean body mass. Participants (n = 33) completed one test wearing a mask and one test without a mask back-to-back with conditions held constant. Dependent-sample sign tests, Bland-Altman Plots, and Passing-Bablok regression analyses were used to test mask-on versus mask-off differences and agreement between variables of interest. RESULTS: There were no significant median differences in any body composition results between face mask use and non-face mask use using dependent-sample sign tests. Bland-Altman Plots demonstrated acceptable agreement between mask usage and non-mask usage. No significant differences were seen in the slopes of the variables using Passing-Bablok regression. CONCLUSIONS: Results suggest that wearing a face mask does not appreciably impact body composition results. Therefore, ASTM level 1 disposable surgical face mask does not introduce a significant amount of isothermal air during BOD POD testing.

Feasibility of structured light Plethysmography (SLP) in patients with coronavirus disease 2019 (COVID-19).

As a result of the COVID-19 pandemic, most institutions have changed the way patients are assessed or investigated. Using novel non-contact technology, it is possible to continuously monitor the lung function of peri-operative patients undergoing cardiothoracic procedures. Primarily, this results in increased patient surveillance, and therefore, safety. Many centres, globally, are starting to use structured light plethysmography (SLP) technology, providing a non-aerosol generating procedure in place of traditional spirometry. While more evidence is needed, our clinical usage; previous and on-going studies; demonstrate definite potential that SLP is a valuable tool.