key: cord-0865255-hr3ykslb
authors: Carlson, John C.
title: Options for Personal Protective Equipment During the SARS-CoV-2 Pandemic Used in New Orleans, Louisiana
date: 2020-05-30
journal: J Allergy Clin Immunol Pract
DOI: 10.1016/j.jaip.2020.05.021
sha: 05df13b56e9daa94fa7ba1d4dc21359cbd8ba6b7
doc_id: 865255
cord_uid: hr3ykslb

nan

The SARS-CoV-2 pandemic has strained supplies and distribution of personal protective equipment 12 (PPE). I have helped set up a drive-through COVID testing site, a COVID treatment facility within the New 13

Orleans Convention Center, and a nursing home strike team, adapting infection prevention to settings 14 that have experienced occasional shortages of all types of PPE in an early epicenter of COVID19. These 15 are strategies that have been used to bridge PPE shortages that may be useful for other clinical settings 16 as patient clinic volumes increase and the breadth of inpatient work expands in the coming months. 17

This Editorial reviews PPE regarding the hands, clothes, eyes, and nose/mouth (Table 1) . 18

The tropism of respiratory tract pathogens make transmission of SARS-CoV-2 through skin unlikely 1 ; 20 thus, virus on hands is not directly dangerous. While RSV is introduced into the respiratory tract when 21 droplets are transferred to nose/eyes from contaminated hands 2 , the importance of fomite transmission 22 varies with different viruses 3 and the relative importance of self-inoculation in SARS-CoV-2 has yet to be 23 definitively determined. When considered as a vector, gloved hands are still able to transfer pathogens 24 between sites and do not obviate the need for proper hand hygiene 4 . In Singapore, a study of 36 25 infected healthcare workers and 50 controls found that gowns and gloves were not found to be 26 important in preventing the spread of the related virus SARS-CoV, while hand washing and N95 use 27 was. 5 In Hong Kong, comparison of 11 healthcare workers infected with SARS-CoV with uninfected 28 controls found only the use of masks (and not gowns, gloves, or handwashing) significant for infection 29 prevention in the final model. 6 Because contaminated hands and surfaces are a mechanism by which 30 some respiratory tract viruses spread 7 and, given the uncertainties of SARS-CoV-2 transmission, we 31 require gloves for patient care for known COVID19 patients. We discourage double gloving (which is 32 more appropriate for blood-borne pathogens) and the use of gloves outside of patient care to conserve 33 supply, emphasizing the need for frequent hand hygiene. The need for gloves when patients are not 34 known to have SARS-CoV-2 is unclear. We require goggles or face shields when coming within 6 feet of COVID19 patients to protect eyes from 48 airborne droplets. The most important properties of protective eyewear are transparency of the 49 material and comfortable fit that holds the shield in place. Face shields may also reduce N95 mask 50 contamination. We have found that disposable face shields in common use are easily decontaminated 51 without reducing visibility or fit through several cycles. We have used dilutions of standard household 52 bleach (1 cup in 3-gallon water bath), 70% or greater concentrations of alcohol (produced by local 53 distilleries) and quaternary ammonium (commercially used by companies routinely performing 54 decontamination of medical facilities) for decontamination of disposable face shields. The former two 55 options take longer to dry; the latter requires manual wiping to remove residue from the face shields 56 before use. These options, along with alternates are recommended by the US Environmental Protection 57

Agency for decontamination of SAS-CoV-2. 8 3D printed and laser-cut face shields work well but are less 58 4 comfortable. These have become readily available from volunteers. In our experience with a variety of 59 designs, these are best used for short patient encounters of 30 minutes or less due to the discomfort of 60 sustained use. Devices that combine respirator and eye protection may be useful when performing 61 aerosol-generating procedures but limit the user's ability to communicate with others or are not readily 62 available. Use of face shields should be considered in treating patients that are sneezing or coughing. 63 64 Nose/mouth 65 N95 masks remove 95% of droplets 0.3-0.5 microns in size. Infectious droplets are ejected into the air 66 near patients that cough, sneeze, and potentially when they speak, and we require N95s for all workers 67 entering within 6 feet of potentially infectious patients. Critical features of N95 masks are the ability to 68 filter these very small particles and the fit of the mask that prevents unfiltered air from being inspired 69 through leaks. There are similar standards globally in certifying masks (eg KN95 masks in China, FFP2 70 masks in Europe), and it is useful to review these alternatives described by the CDC for times when 71 NIOSH-approved N95 masks are unavailable. 9 We, as well as other hospitals, have received counterfeits. 72

Those procuring supplies should become familiar with the process of verifying certificates of these 73 products. A wide variety of community-created masks have been proposed as alternatives to N95s but 74 fail to provide adequate filter and/or fit. At the minimum, candidates should pass standard fit testing. 75

We have tried a variety of models in New Orleans and have yet to find a community-created mask 76 capable of passing a fit test. 77

Shortages of N95 masks have prompted alternative strategies to preserve N95 use to the most critical 78 procedures. The CDC and JHACO have suggested use of standard surgical masks for procedures where 79 aerosolization is unlikely, as one N95 preserving measure. Surgical masks have filtering functions but 80 not fit, meaning that infectious particles will be inhaled through the gaps in the mask. Surgical masks 81

Factors associated with transmission of 128 severe acute respiratory syndrome among health-care workers in Singapore

Advisors of Expert SARS 131 group of Hospital Authority. Effectiveness of precautions against droplets and contact in 132 prevention of nosocomial transmission of severe acute respiratory syndrome (SARS)

Potential role of hands in the spread 135 of respiratory viral infections: studies with human parainfluenza virus 3 and rhinovirus 14

List N: Disinfectants for Use Against 138

Strategies for Optimizing the Supply 141

Reaerosolization of MS2

bacteriophage from an N95 filtering facepiece respirator by simulated coughing

Centers for Disease Control and Prevention

Aerosol and Surface Stability of SARS-CoV-2 as 150 Compared with SARS-CoV-1

were designed to prevent infection coming from the surgeon to the patient, and not as PPE protecting 82 the surgeon, though they are now being endorsed as such. The CDC has issued descriptions of reuse 83 strategies to further conserve N95 masks. N95 reuse has become common as supplies are depleted and 84 supply chains are themselves unstable. 9 A common strategy involves the re-use of a mask for an 85 individual patient over multiple visits. For example, the worker uses a fresh mask in the morning, doffs 86 the mask being careful not to touch the inside of the mask, and then re-uses the mask when seeing the 87 patient later that day. This increases the risk to the healthcare worker if the inside of the mask becomes 88 contaminated during the doffing or re-donning process. To re-don a contaminated mask, gloves are 89 commonly worn, depleting glove supplies. "Extended use" refers to the continuous use of a single N95 90 while seeing multiple patients. Because the mask is not removed between patients, risk of self-91 contamination is low and we have adopted this practice. If the outside of the mask becomes 92 contaminated from inspired air, it is theoretically possible for infectious particles to be ejected back into 93 the ambient air, posing a risk to new patients. Experiments suggest that the likelihood of this happening 94 is low. 11 95Decontamination of masks allows a mask to be reused with minimal risk to the worker or patient. 96Decontamination can be achieved without compromising the fit or filter of masks using vaporous 97 hydrogen peroxide, ultraviolet germicidal irradiation, and moist heat. 11 Theoretically masks could be 98 returned to use within the same day. Transport of the mask between sites and processing makes a 99 several day turn-around more common. An additional approach to decontamination is allowing 100 sufficient time to elapse between use for the virions to become non-infectious based on viability 101 studies. 12 The CDC suggests a 5-day interval between uses. As with other methods of decontamination, 102 it is important to discard the mask if there is gross contamination, or if inhalation while wearing the 103 mask fails a user-seal test. 9 We do not allow mask reuse within a shift but save all masks for 5 days in