Examination of the Effects of 4-Hour Nonvalved Filtering Facepiece Respirator Use on Blood Gas Values of Health Care Professionals: A Before and After Study

Nonvalved filtering facepiece respirators are frequently used by nurses, paramedics, and other health care personnel who intervene in suspected and diagnosed patients with COVID-19, especially during the pandemic with high respiratory transmission.The main finding of this article is that continuous nonvalved filtering facepiece respirator use for 4 hours was not associated with impairment in blood gas and peripheral SpO2 levels during nonexertional clinical work in the emergency department. A statistically significant increase was observed in pH values, which remained within physiological limits and may not have clinical significance.Recommendations for translating the findings of this paper into emergency clinical practice include the following: continuous 4-hour use of nonvalved filtering facepiece respirators does not appear to have a negative impact on clinician respiratory physiology.