Effects of N95 Masks on Cerebral Oxygen Saturation and End-Tidal Carbon Dioxide Partial Pressure in Healthcare Workers

 Healthcare workers must wear masks throughout their shifts, especially those in operating rooms for long periods.

 This study evaluated the effects of wearing N95 masks on blood and cerebral oxygen saturation levels for three hours.

 The present case-control study enrolled 20 operating room workers wearing N95 masks. Their blood oxygen saturation (SaO2), end-tidal carbon dioxide partial pressure (PETCO2), and right- and left-sided cerebral oxygenation (rSO2) were measured in the beginning (0 h) and after wearing N95 masks for one and three hours.

 Wearing a mask affected PETCO2, rSO2, and pulse rate and caused fatigue and lightheadedness in some cases. The participants' mean PETCO2 increased significantly, from 32 mmHg before putting on a mask to 38 mmHg after wearing it for three hours (P < 0.05). No significant change was observed in the participants' mean rSO2, though changes in their rSO2 levels were recorded (P > 0.05).

 We showed evidence of changes in different physiology parameters due to using masks for 1 to 3 h. Notably, wearing an N95 mask increased end-tidal carbon dioxide partial pressure and decreased cerebral oxygen saturation in individual cases, not all cases.