Copyright © 2020 Albuquerque Journal
Wearing a face mask as protection against COVID-19 causes people to rebreathe carbon dioxide and other compounds that ought to get exhaled, particularly when exercising, and can cause lung damage. That’s a commonly heard rationale from some people who are reluctant to wear a face covering, and it’s also just plain wrong, according to two pulmonary medical professionals.
Dr. Denise A. Gonzales, a pulmonary critical care physician with Presbyterian Hospital, said for most people with normal lung function, wearing a mask doesn’t result in any significant increases in carbon dioxide.
“While there is a small amount of rebreathing, your body knows how to compensate and breathe a little bit faster to get that carbon dioxide out,” she said.
John Blewett, director of pulmonary services and respiratory therapy at the University of New Mexico Hospital, said there is no scientific evidence that wearing a mask causes retention and buildup of carbon dioxide.
What is known is that people who are engaged in “a high level of aerobic exercise while wearing a mask may find that the mask restricts the rapid flow of inhaled air,” he said.
What people need to be mindful of when exercising while wearing a mask is to “work out at a level where they’re keeping their heart rate in a target range, and know that it may take less time to get there” because their respiratory system is working a bit harder than it normally would without a mask, Blewett said.
In addition, exercising or normal breathing through a mask does not cause lung damage, such as pleurisy, an inflammation of the lining of the lungs, as some have suggested.
“Otherwise, I should have developed pleurisy years ago because I wear masks quite a bit at work,” Gonzales said.
People who have lung disease and get supplemental oxygen delivered through a tube, or cannula, that sits in the nostril openings, actually increase the amount of oxygen delivered by the cannula when they wear a face mask over it, Gonzales said.
That technique is used in hospitals, even on COVID patients who get oxygen through a cannula, she said.
Further, Gonzales said, athletic trainers have for years used special training masks for student athletes. These masks can be adjusted for ease or difficulty of breathing, which simulates different elevations and improves cardiovascular stamina.
Blewett suggests that people exercising for lengthy periods bring one or more spare masks to change into because masks can become wet and uncomfortable due to respiratory condensation.
Another common excuse for not wearing a mask is that the materials or fabrics from which masks are made can be irritating, as can the fragrances infused in the manufacturing of some masks or the detergents used in washing fabric masks.
This can be true, particularly for people who are asthmatic and are more sensitive to chemicals, both Gonzales and Blewett said.
Where personal protective equipment has been in short supply, some people have reported irritation after wearing masks, including disposable masks, that have been reused and sprayed with a disinfectant.
“I would recommend they switch to a mask that’s made from a woven fabric and wash it in perfume-free detergent,” Gonzales said.
According to state Health Department spokesman David Morgan, the governor’s orders regarding the wearing of masks are informed by “best practices and guidelines established by the Centers for Disease Control, and are particularly critical when social distancing is difficult.”
There are situations when wearing a mask may not be feasible, and the state recognizes that, Morgan said.
This may apply to children under age 2; people who have documented breathing conditions, such as COPD, chronic obstructive pulmonary disease; children or adults with medically documented mental health conditions or sensory sensitivities; and in situations where lip reading is essential for people who are deaf or hard of hearing and those who interact with them.
There is a growing body of science that indicates the COVID-19 virus can remain airborne, though the duration is not clear, Morgan said. “So even if someone is outside walking or bicycling on a trail alone, they could still be at risk and not even know it. That’s why the scope of the governor’s order is broad and requires that people wear a mask when outside at all times.”
Swimming is an example of an exercise that makes wearing a mask near impossible. “But even swimmers are expected to observe social distancing and maintain a physical distance from other swimmers in the water,” Morgan said.
Perhaps the most dangerous misunderstanding regarding masks is that there is no need to wear one in the first place, Gonzales and Blewett said.
The single biggest reason for a person to slip a mask over their nose and mouth is because it traps droplets of moisture, preventing them from becoming airborne and possibly infecting others, as well as provides a barrier against inhaling an infected airborne virus from others, they said.