Life in the Time of Coronavirus - Brought to you by Dr. MZ
PPE: What Makes Sense and What Doesn’t?
Everybody is wandering around nowadays wearing various versions of what they think is personal protective equipment (PPE). You see people in grocery stores with nitrile or latex gloves on, people wandering the halls with face shields, people on the street with bandanas, scarves, and neck gaiters, people with surgical masks hanging down around their necks, people with their noses sticking up above their surgical masks, even people with bags over their heads. People are understandably scared but are not always thinking rationally about the underlying principles that drive the correct use of PPE. Let’s lay out some basic principles that might lead to more effective use of PPE.
1) Cloth masks are not PPE. Wearing a cloth mask is NOT for your protection. Cloth masks do not protect the wearer. If they have benefit, and the Asian experience suggests that they may, it is a population-based benefit and the benefit is for others. Others are protected from the large droplets that we all emit from our nasal and oral cavities (spit and snot to put it bluntly). We emit these droplets when we breathe, talk, sneeze, laugh, sing, shout, scream, and otherwise expel air through our nose and mouth. We have been asked to wear cloth masks when we go outside. We all seem to want to believe that we are wearing these cloth masks for our own protection. This is simply not true. Wearing a cloth mask doesn’t mean you can come within 6 feet of someone without risk and it doesn’t mean you can go out in large gatherings without risk. I’ve noted that since the orders to wear a cloth mask in public were issued traffic has increased. That’s not good because it signals that people feel less afraid with masks on and believe they are at less risk. This notion is false. We wear cloth masks to protect others and if everyone does it and stays outside of large droplet range (6 feet) we will all gain some measure of protection.
2) The purpose of PPE is to protect the wearer from exposure to and subsequent infection with a pathogen (in this case SARS-CoV-2). When a healthcare provider (HCP) puts on full PPE, they are trying to protect themselves. An HCP caring for COVID-19 patients is heavily exposed to the virus especially when they are performing procedures such as intubation that make patients cough. Therefore, optimal PPE for them includes at least one gown or a TYVEK™ bunny suit, head covering, goggles and/or a face shield, an N95 mask, gloves, and shoe covers. There is a specific order and protocol that must be followed while donning all of that and HCPs should be observed as they don it to be sure that there are no mistakes in the protocol. Usually, glove cuffs are taped to the gown sleeves so that there is no break in the interphase between gown and glove. When the HCP removes the PPE, there is again a proper order and protocol for doffing the PPE and the doffing procedure must be observed for breaks in technique. The doffing procedure involves much hand washing or hand sanitizer and several sets of gloves. The really intense use of full PPE is time consuming, intricate, requires training, and consumes a lot of resources both in humans and PPE stock. Wearing full PPE is exhausting, hot, and uncomfortable. Hence the many pictures of HCPs with tired and bruised faces. Working for long periods of time in all this gear is brutal.
3) The best mask of all (short of a power-assisted air-purifying respirator (PAPR) which is battery powered and blows clean air in for the wearer to breath) is an N95 mask which is so named because it filters out 95% of particles down to 0.3 microns in size and in doing so protects the wearer. If the infectious risk is real, close, and intense, an N95 mask should be worn. N95 masks are in short supply and at this time are primarily reserved for HCPs in hospital or home healthcare settings.
4) Goggles and face shields are simply to protect your eyes and your ocular mucous membranes from body fluid splashes, e.g., sputum, oral and nasal secretions, broncho-alveolar lavage fluid, and tracheal aspirates. These body fluids are usually only encountered in hospitals during procedures although they might be a problem when inserting nasal swabs during testing. Goggles and face shields do not provide any significant protection against small aerosols and when worn properly should always be worn with a mask. Wearing a face shield alone out in public is useless.
5) From an infectious perspective, gloves are not useful except in specific circumstances and sometimes may be worse than not wearing them at all. Except in the hospital with patients all of whom have COVID-19, or when seeing patients in contact isolation in the hospital, gloves are not useful for protection and they may lead to greater exposure. Gloves become contaminated almost as soon as they are donned. If they are worn for an extended period of time, they are thoroughly contaminated. Unfortunately, people who wear gloves tend to feel that they are magically protected and they wear them for long periods of time completely forgetting to not touch their face. Gloves are not impermeable, even latex or nitrile gloves. There is a proper technique for removing gloves that ensures that the outside of the glove does not contaminate the wearer. This means carefully removing them such that the inside of the glove envelopes the entirety of the used glove. Glove removal should be followed by careful handwashing. Used gloves must be disposed of properly in the infectious waste. People who are not in the hospital and are using gloves are generally not trained to do this and are likely to contaminate themselves with their used gloves. Additionally, gloves cannot be washed and are designed for single use only. Wearing of gloves removes much of the tactile sense that we all have in our hands, including the tactile warnings that we should wash our hands and not touch our face because we just touched something that might be contaminated. In short, gloves for protection from SARS-CoV-2 outside of the hospital unless one is caring for a COVD-19 patient, are really a bust and should not be used.
6) Surgical masks are for the protection of the wearer and are about 60% effective in screening out small particle aerosols. They do also catch large droplets emitted by the wearer and so do provide some protection to others in a population sense similar to cloth masks. In a hospital or testing setting, they should be used with a face shield or goggles. For intense infectious exposure for the wearer, an N95 mask is clearly preferable. Surgical masks were designed originally to prevent a person in the operating room from expelling large respiratory droplets at close range into the surgical field (meaning the open surgical wound) and should be reserved, as much as possible for HCP use.
7) Fresh air is your friend. Small viral particles that circulate and hang in the air in aerosols are hugely diluted in the outside air. Confined and small spaces that contain viral particles in aerosol form are much more infectious. Open windows, windy weather, breezes, and outdoor spaces are all exceptionally useful in dispersing tiny viruses and lowering risk.
The principles of PPE are not difficult but effective use of PPE requires careful and rational thought. For most of us not in a hospital or home healthcare setting, all we need to know is how to wear a cloth mask and we need to understand who we are protecting. Beyond that, staying 6 feet away from others, washing our hands frequently, not touching our faces, and sheltering at home as per our respective health departments and state governments are what we should be doing.
Please feel free to send questions and concerns about COVID-19 and this pandemic to //healthcare [at] lwv-pa.org">healthcare [at] LWV-PA.org.
Stay safe and don’t forget to stay home, wear your mask in public, wash your hands frequently, stay six feet away from others, and, as much as humanly possible, don’t touch your face. This will come to an end and we will return to some version of “normal.” Just not yet…….
Dr. Margan Zajdowicz is the Co-Chair of the League of Women Voters-Pasadena Area Healthcare Committee and a retired infectious disease physician who spent many years in clinical practice and emergency preparedness and pandemic planning for the US Navy. She holds a Doctor of Medicine degree from the University of Maryland School Of Medicine and a Master of Public Health degree from Old Dominion University/Eastern Virginia School of Medicine.