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

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 (PaCO), 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 (3M Aura) 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 PaCO (the baseline value: 29.3 mm Hg, the max. value: 38.9 mm Hg) and a continuous decrease in partial pressure of oxygen (PaO, 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.