In a study conducted by the National Taiwan University Hospital fifteen years ago, it was found that the use of N-95 masks in healthcare workers caused them to experience hypoxemia, a low level of oxygen in the blood, and hypercapnia, an elevation in the blood’s carbon dioxide levels. Not only did the mask create dangerously low levels of oxygen and an equally dangerous spike in carbon dioxide in the human body, the study found that “medical staff are at increased risk of getting ‘Severe acute respiratory syndrome’ (SARS) [from] wearing N95 masks….” Lastly, the study’s authors further found that “dizziness, headache, and short[ness] of breath are commonly experienced by the medical staff wearing N95 masks” and that the “ability to make correct decisions” was also likely impaired. The Physiological Impact of N95 Masks on Medical Staff, National Taiwan University Hospital (June 2005).
Studies show that headaches in medical professionals are commonly found as a result of mask-wearing, which is a sign of hypoxia: Just under 10% of the healthcare workers in one study experienced such severe symptoms that they were forced to take, on average, two full days of sick leave from their healthcare jobs, while 60% of these healthcare professionals “required use of abortive analgesics because of headache.” Headaches and the N95 Face-Mask Amongst Healthcare Providers. Lim EC1, Seet RC, Lee KH, Wilder-Smith EP, Chuah BY, Ong BK, Acta Neurologica Scandinavica, 28 Feb 2006, 113(3):199-202.
A more recent study involving 159 healthcare workers aged 21 to 35 years of age found that 81% developed headaches from wearing a face mask – which is a sign of dangerously low levels of oxygenation – and ALL healthcare workers felt like the headaches affected their work performance. Ong JJY et al. Headaches associated with personal protective equipment- A cross-sectional study among frontline healthcare workers during COVID-19. Headache 2020;60(5):864-877.
In this study, researchers examined the blood oxygen levels in 53 surgeons. They measured blood oxygenation before surgery as well as at the end of surgeries. The researchers found that the mask reduced the blood oxygen levels significantly. The longer the duration of wearing the mask, the greater the fall in blood oxygen levels. Bader A et al. Preliminary report on surgical mask induced deoxygenation during major surgery. Neurocirugia 2008;19:12-126.