effects of n95 masks on cerebral oxygen saturation and end-tidal carbon dioxide partial pressure in healthcare workers

Background: healthcare workers must wear masks throughout their shifts, especially those in operating rooms for long periods. objectives: this study evaluated the effects of wearing n95 masks on blood and cerebral oxygen saturation levels for three hours. methods: 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 regional oxygen saturation (rso2) were measured in the beginning (0 h) and after wearing n95 masks for one and three hours. esults: 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). conclusions: 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.