The effect of wearing an FFP3 mask (3MTM AuraTM) with an exhalation valve on gas exchange in medical staff.

ABSTRACT

OBJECTIVES: The physiological impact of wearing personal protective equipment (PPE), in particular filtering-face-piece 3 (FFP3) masks, has increasingly been gaining importance since the outbreak of coronavirus disease 2019 (COVID-19). So far, gas exchange has been examined using transcutaneously measured partial pressure of carbon dioxide (PaCO2), ergo-spirometry and impedance cardiography. MATERIAL AND METHODS: In this structured investigation, arterial blood gas analysis in a 30-year-old female resident was carried out during a 13-hour day shift on the COVID-19 Intensive Care Unit of the University Hospital of Innsbruck, Austria. An FFP3 mask (3MTM AuraTM) with an exhalation valve was continuously worn, except for 1 break of 20 min. Arterial blood samples were obtained before putting on the PPE, and after 5 h, 9 h and 13 h of working in the contaminated area. RESULTS: During the multi-hour wearing time, an increase in PaCO2 (the baseline value 29.3 mm Hg, the max. value 38.9 mm Hg) and a continuous decrease in partial pressure of oxygen (PaO2, the baseline value 102 mm Hg, the min. value 80.8 mm Hg) was detectable. CONCLUSIONS: All measured values were within the normal range, but a trend towards an insufficient gas exchange could be suspected. Int J Occup Med Environ Health. 2021;34(6)817-9.