Physiologic Effects and Symptoms Associated with Extended-Use Medical Mask and N95 Respirators

Ann Work Expo Health. 2021 Aug 5;65(7):862-867. doi: 10.1093/annweh/wxab010.

Abstract

Objectives: Compliance and tolerance of facemasks for extended periods are legitimate concerns. The goal of this study was to identify the physiologic and symptomatic effects of extended-use N95 filtering facepiece respirator (N95) compared with medical masks. We hypothesized that hospital personnel wearing medical masks alone would report fewer subjective complaints compared with personnel wearing an N95 with or without overlying medical mask.

Methods: This was a nonrandomized cohort study of hospital-based healthcare personnel at a single tertiary center wearing a medical mask alone or N95 with or without overlying medical mask during routine clinical activity. Potential subjects were consented and asked to complete a structured survey, including a 10-point Likert scale for subjective symptoms: headache, lightheadedness, breathlessness, facial bruising, facial irritation, mental fatigue, physical fatigue, and yawning. Study investigators also obtained vital signs on the participants. Results between subjects wearing a medical mask and subjects wearing an N95 were compared. A sample of 144 subjects, 72 in each mask cohort, was needed to detect a 20% difference in a composite outcome of headache, shortness of breath, or lightheadedness between groups with an alpha of 0.05 and power of 0.8.

Results: We enrolled 72 subjects in each group. There were no differences in baseline demographics. Overall 77% of the cohort reported subjective symptoms while donning a mask. There was no difference in the composite outcome, no difference recorded symptoms except facial bruising, and no difference in physiologic measures between groups.

Conclusions: Most medical mask and N95 users reported symptoms during mask use. However, there was no difference in the symptom proportion or severity in either user.

Keywords: N95; PPE; facemasks; medical mask.

Publication types

  • Clinical Trial

MeSH terms

  • COVID-19*
  • Cohort Studies
  • Humans
  • Masks
  • N95 Respirators
  • Occupational Exposure*
  • SARS-CoV-2