Effect of surgical mask and N95 respirator mask use on cerebrovascular reactivity.

Abstract

<p>Face masks are crucial parts of personal protective equipment (PPE) to reduce the risk of respiratory infections. The COVID-19 outbreak has increased healthcare workers&rsquo; use of face masks. This study aimed to evaluate changes in cerebrovascular response among healthcare workers using surgical and N95 respirator masks.&nbsp;</p>. <p>90 healthcare workers: 30 wearing surgical masks, 30 wearing N95 respirators, and 30 without masks were included. After two-hour of face mask use, the baseline mean flow velocity (MFV) and the mean breath-holding index (BHI) of the bilateral middle cerebral arteries (MCAs) were evaluated with transcranial Doppler ultrasound. The presence of de-novo headache was recorded. BHI values ​​below 0.69 were evaluated as a sign of impaired cerebrovascular reactivity (CVR).&nbsp;</p>. <p>The rate of de-novo headache was significantly higher in the N95 respirator mask group (p = 0.004). Compared to the control and surgical mask groups, the N95 respirator mask group had significantly lower values of the baseline MFV of the right MCA (p = 0.003 and p = 0.021, respectively) and mean BHI (p = 0.003 and p = 0.012, respectively). Still, only one N95 respirator mask user had a mean BHI value below 0.69.</p>. <p>Surgical masks did not signi&shy;fi&shy;cantly affect cerebral hemodynamics. Although N95 respirator mask use significantly decreased BHI values, the CVR is still within normal limits, and the development of de-novo headache is not directly associated with low CVR.&nbsp;</p>.