nurses wearing face masks
© Susan Merrell
Prolonged wearing of a surgical face mask, made compulsory in many settings in many countries during the Covid years, reduces cognitive function and increases reaction time in addition to increasing shortness of breath and fatigue. These are the findings of a study published in Nurse Education in Practice, an international peer reviewed journal, on September 15th 2023.

The study, carried out in Turkey and titled 'The effect of prolonged use of surgical masks during face-to-face teaching on cognitive and physiological parameters of nursing students: a cross-sectional and descriptive study' involved 61 nursing students who volunteered to participate in the study. The sample size was determined to be adequate for the study using the statistical method of power analysis. Information was collected on cognitive fatigue and dyspnoea (shortness of breath) using a self-administered questionnaire and cognitive reaction time was measured objectively using an app. Body temperature and blood oxygen saturation were also measured.

The students were asked to complete the questionnaires and measure the above parameters at the start of a five-hour class and to repeat the process at the end. Surgical face masks were worn for the duration of the class. With the exception of blood oxygen saturation, all the remaining parameters were adversely and statistically significantly affected over the course of the class.

At the end of the class, the students reported greater shortness of breath, cognitive fatigue and had demonstrably slower reaction times. They experienced a rise in body temperature which is an established correlate of physical fatigue.

The authors of the study are careful to point out that the design of their study was a pre-test/post-test where the participants were, effectively, acting as their own controls. It is possible, therefore, that alternative explanations may exist to explain the observations. For example, we do not know if or to what extent the observed changes in parameters may have taken place anyway after five hours in class. For that reason, as recommended by the authors, further study is required of these phenomena using a parallel control group who undergo the five-hour class but who are not subjected to wearing surgical face masks for the duration. The reported study was carried out under Covid restrictions, therefore, there was no possibility of incorporating a control group.

Assuming that the outcome of the study does provide evidence for the adverse effects of face masks then further study should be conducted. Furthermore, the implications of the study could be very important if transposed to clinical practice. Prolonged wearing of surgical (and even more restrictive) face masks was compulsory during Covid restrictions. The ramifications for the ability of clinicians to make the correct decisions and to act quickly in emergency situations are surely worrying.
Dr. Roger Watson is Academic Dean of Nursing at Southwest Medical University, China. He has a PhD in biochemistry. He writes in a personal capacity.

Declaration of interests: the author is Editor-in-Chief of Nurse Education in Practice.