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As more jurisdictions mandate facial coverings in public, questions have arisen about whether it’s safe for everyone — including those with lung disease — to wear masks. Stories about people who claim to be unable to wear masks because of breathing problems are appearing in the news with increasing frequency, and patients are starting to call their doctors to request medical exemptions to public mask requirements.

To address these issues, Medscape spoke with the chief medical officer of the American Lung Association, Dr Albert Rizzo.

The CDC recommendations on mask wearing say, “Cloth face coverings should not be placed on young children under age 2, anyone who has trouble breathing, or is unconscious, incapacitated, or otherwise unable to remove the mask without assistance.”

Does this language suggest that there indeed is a subset of the adult population with lung disease who shouldn’t wear masks?

It makes sense to say that if it makes you uncomfortable to wear a mask because it affects your breathing, you should think twice about getting in a situation where you would have to wear a mask.

I’ve told many of my high-risk patients, “The best way to avoid getting COVID-19 is to stay home and stay away from sick people, especially if you feel that you are not going to be able to wear a mask or facial covering of some sort.”

The reason that some people have trouble with a mask is that they haven’t tried the right style of mask — by that I mean how tightly it fits and the material it’s made out of. Sometimes it really is just that people with lung disease don’t like to have anything covering their faces. Many of these patients feel better where there is air blowing across their faces — they will have a fan blowing even in the middle of winter because they feel more comfortable.

I won’t say it’s all in their heads, but sometimes it’s a matter of desensitizing themselves to wearing a mask. I liken it to people who have sleep apnea. We often have to desensitize them to wearing a mask for sleeping. We tell them to put it on while they are watching TV — don’t hook it up to anything yet, just get used to having something on your face.

I’ve told my patients the same thing about masks for COVID-19. Put on the mask, see how it feels. If you become uncomfortable breathing with it on, take it off, but maybe you can handle it for a half hour or 45 minutes. Find out how much time you have for a trip to the grocery store based on how comfortable you are wearing it at home.

It’s a matter of training the patient, giving them options of how to get comfortable with it, and then making them realize that they have to weigh the benefits and risks of wearing the mask and feeling out of breath versus going out in public and being potentially exposed to coronavirus. And the bottom line is, anybody who is wearing a mask and starts to feel uncomfortable, they can take the mask off.

You mentioned different types of masks. Is there a type of mask that is typically more breathable that clinicians can recommend to patients with lung disease?

First, I remind patients who think they will have trouble breathing with a mask on that they are choosing a mask not so much to protect themselves — that would take an N95 mask to filter out the virus. The mask is worn so that when they cough or drink or speak, they aren’t sending respiratory droplets out into the environment. Even when we speak, respiratory droplets can easily go out as far as 6 feet, or further with coughing or sneezing. With facial coverings, we try to keep those respiratory droplets from getting out and infecting others.

So when choosing a mask, you don’t have to worry as much about a tight-fitting mask. I recommend a loose-fitting mask that covers the nose and mouth and isn’t going to fall off but isn’t so tight around the ears and neck to make them feel uncomfortable. Even though it doesn’t really protect the wearer, it is cutting down on the ability to breathe in droplets ― maybe not microscopic particles, but it’s better than nothing.

Is a face shield a reasonable alternative for someone who feels they can’t breathe with a mask on?

Yes. I’m surprised that face shields don’t get more attention. I’ve tried them out, and they are actually more comfortable than masks. They do impede the spilling out of droplets into the public, but they are not as close fitting to the face as a mask. If you want to protect others, the face shield should be adequate. It is not as good at preventing you from breathing in viral particles.

Some people have claimed that wearing a mask makes them hyperventilate and feel like they are going to pass out, or the mask causes them to become hypoxic. Are these valid concerns?

We get two questions about masks from patients who feel that they are short of breath or are worried about wearing a mask. One is whether their oxygen level is dropping. It’s usually not that. It’s usually because they feel that the mask is an impediment to getting air in. Their oxygen levels are stable.

The other question is whether the mask causes CO2 retention. For the mask to trap enough exhaled CO2 and for us to breathe enough of that CO2 back in to raise our CO2 level, it has to be a pretty tight-fitting mask. With the type of masks we are suggesting that people wear, that’s very unlikely to occur.

What can clinicians do to reassure patients with some type of lung disease that they can safely wear masks?

There are a few things they can do right in the office. Have them put the mask on for a few minutes and make sure they feel comfortable with it. With an oximeter, patients can see that their oxygen levels don’t change when they are breathing through the mask for a period of time.

You can’t really measure CO2 retention that easily, but most patients with chronic obstructive pulmonary disease or pulmonary fibrosis don’t have an elevated CO2 at baseline. A little more education is helpful in those situations. In most cases, they aren’t going to retain enough CO2 to have problems wearing a mask.

Only a small percentage of patients with lung disease are CO2 retainers, and many of those patients are being seen by pulmonary specialists. Those are the patients you might want to be more cautious with, to make sure they aren’t wearing anything that is tight fitting or that makes them work harder to breathe. It’s not that the mask is causing CO2 retention, but the increased work of breathing may make it harder to exhale the CO2.

Does a mask interfere with supplemental oxygen in any way?

Supplemental oxygen is typically supplied through a nasal cannula, so 100% oxygen is still getting to the nasal passages and entrained down into the airway, so it shouldn’t be a problem.

Some of the resistance to wearing masks has come from people with asthma. Is it safe for patients with asthma to wear masks, or should these patients be exempt from wearing masks?

In general, the breathing of people with mild asthma, both young and old, should not be impeded by the wearing of facial coverings. The concerns about oxygen and carbon dioxide among patients with more severe lung disease should not play a role in asthma.

Since younger adults with COVID-19 seem to have fewer or no symptoms and may actually be carrying the virus unknowingly, this should be the main population who should wear masks to prevent transmission to others.

Exemptions for mask wearing for mild asthma should be discouraged and dealt with on a case-by-case basis if there is a particular concern for that individual.

How do you respond if a patient asks you for a formal medical exemption to wearing a mask?

We’ve been asked to do a lot of letter writing for patients around going back to work as well as the issue of wearing masks. The discussion usually revolves around trying to avoid going somewhere where you would have to wear a mask if it makes you feel uncomfortable.

I do not recommend automatically exempting individuals from wearing masks, even many of my pulmonary patients. There needs to be an understanding by the patient regarding the purpose of the mask and the overall advice to stay out of situations where social distancing is not being practiced. If you can take the time to discuss options as mentioned above — mask styles, desensitization, etc — the patient usually understands and will try wearing a mask.

On a case-by-case basis, some individuals may need to be exempted, but I feel this is a small number. I prefer my high-risk (older, chronic disease, etc) patients do everything they can to avoid infection — handwashing, mask wearing, and socially distancing.

They should also realize that even with a note, it is not going to help if they are in the middle of the grocery store and someone confronts them about not wearing a mask. It may help as they enter a store that says “masks required” and they can show it to someone monitoring the door. But I’m not really sure in what situations having that note is going to be helpful if confrontations occur.

Patients are also asking how safe is it for them to go back to work and be out in public. I tell them, nothing is going to be 100% safe. Until we have an effective vaccine, we are all going to have to weigh the potential risks of going to an area where social distancing isn’t maintained, people aren’t wearing face masks, and you can’t wash your hands as much as you’d like to. That’s going to be a struggle for all of us to get back out into situations where people interact socially.

Albert A. Rizzo, MD, is chief medical officer for the American Lung Association, chief of the Section of Pulmonary and Critical Care Medicine at the Christiana Care Health System in Newark, Delaware, and a member of Christiana Care Pulmonary Associates. He is board certified in internal medicine, pulmonary medicine, critical care medicine, and sleep medicine and is a clinical assistant professor of medicine at Thomas Jefferson University Medical School.