Healthcare workers have died, become critically ill, sustained injury/disability from COVID-19. All means must be deployed to protect HCWs.
- Over 600 US HCWs have died of COVID-19
A core principle of emergency response / hazardous materials management training has always been safety first. This is even taught in every CPR class, never enter an unsafe scene. COVID-19 is no different and I think we have learned some important lessons. If we are entering a room and are unsure of the appropriate PPE/precaution level, safety should always be maximized. Over protect then downgrade as evidence becomes available.
Excellent Sustainable / Long-term Respiratory PPE options:
1. Elastomeric, vented, reusable, respirators
These have been used around the world during epidemics for decades. Much cheaper than PAPRs, one is assigned to each healthcare worker (individual accountability), more comfortable, highly effective. These are particularly well suited for triage, evaluating a large number of patients, managing a cohort unit.
- Reusable Elastomeric Respirators in Health Care: Considerations for Routine and Surge Use.
- CDC – Elastomeric / PAPR
3M Models and Filters
PROS- very comfortable, easily sanitized (there is a 3M white sheet on this), minimal inhalation/exhalation resistance, easy to fit test with no additional equipment, low cost
CONS- difficulty hear speech which is muffled by the device
2. Powered Air-Purifying Respirator (PAPR)
PROS- excellent protection, easily sanitized, no respiratory resistance
CONS- more equipment to manage, battery charging/runtime, increased weight, cost
- Respirator Trusted-Source Information
- CDC N95 Respirators and Surgical Masks
- 95 Respirators and Surgical Masks
- BMC- IRD: the cough bioaerosol
- BMC- Recognition of aerosol transmission of infectious agents: a commentary
- PANS-Infectious Virus in Exhaled Breath of Symptomatic Seansonal Influenza Cases
- AJRCCM- Face Masks and Cough Etiquette Reduce the Cough Aerosol Concentration of Pseudomonas aeruginosa in People with Cystic Fibrosis
- JAMA-Turbulent Gas Clouds and Respiratory Pathogen Emissions
- APSF- Perioperative Considerations for COVID-19
- Recommend N95 /PAPR
- BJA- Anaethesia and SARS
- Recommend N95 / PAPR
- CJA- Intubation of SARS Patients: Infection and Perspective of Healthcare Workers
- During SARS – 1 protection guidelines failed to completely prevent the transmission of SARS to HCWs.
- HHS- Dispersion and Exposure to a Cough- Generated Aerosol in a Simulated Medical Examination Room
- N95s were effective in this simulation. Surgical masks did not provide adequate protection.
- CADTH- Respirator Precautions for Protection from Bioaerosols or Infectious Agents: A Review of the Clinical Effectiveness and Guidelines
- LANCET- Effectiveness of precautions against droplets and contact in prevention of nosocomial transmission of SARS
- 11 index cases, 13 staff infections
- SARS-CoV (NOT 2)
- 92/241 non infected staff were using N95
- 30% of the non-infected staff did not use a mask
- Recall bias a concern (this study was a survey)
- CMA- Effectiveness of personal protective measures in prevention of nosocomial transmission of severe acute respiratory syndrome
- Case control study
- SARS-CoV (NOT 2)
- 180 non-infected and 77 infected HCWs
- Conclusion: Recommended droplet and personal contact precautions
- JAMA- Surgical Mask vs N95 Respirator for Preventing Influenza Among HCW
- Noninferiority RCT
- Influenza. NOT SARS-CoV-2
- 446 HCW
- >62% of the HCW were vacinated against influenza
- Conclusion: Surgical masks (type not specified) appear to be similar to N95 respirators with respect to protection against influenza. Cannot be generalized to aerosols.
- JAMA- N95 Respirators vs Medical Masks for Preventing Influenza Among Health Care Personnel
- Cluster randomized pragmatic effectiveness study
- Influenza. NOT SARS-CoV-2
- 2500 HCWs
- 3M N95, Precept 15320 surgical masks (L3)
- Infection rate 7-8%
- 75% were immunized
- Conclusion: no difference between surgical masks (L3) and N95
- CMAJ- Effectiveness of N95 respirators vs surgical masks in protecting health care workers from acute respiratory infections: a systemic review and meta-analysis
- SM- Debate on MERS-CoV respiratory precautions: surgical mask or N95 respirators?
- Aerodynamic Analysis of SARS-CoV-2 in Two Wuhan Hospitals
- PNAS- Identifing Airborne Transmission as the Dominate Route fo rthe Spread of COVID-19
News / Updates
- Keeping the Coronavirus from Infecting Health-Care Workers
- OSHA -> includes elastomeric respirators in 3/14/2020 memo
- University of Maryland Medical Center has no Shortage of Respirators-> They have a backup supply of elastomeric respirators.
- HonorHealth Healthcare Team- All in elastomeric respirators
- IDSA Guidelines
- Germany Jena Study -> Facemasks Flatten the Curve
- Letter – Recommending ‘Airborne’ Designation for SARS-CoV-2
- WHO- Transmission of SARS-CoV-2
- Acknowledges the possibility of airborne transmission (7/9/20)
Data / Evidence / Events Suggestive of Aerosol Transmission
- Choir Rehearsal -> Dozens have COVID-19
- +600 Massachusetts hospital workers test positive.
- Unclear if these infections are from the community, PPE related, HSW to HSW infections.
- Bloomberg- Cotugno Hospital in Napes -> No HCW Infections -> Reusable Respirators / Eye Protecion / Coveralls / Strict Separation
- ACEP- Announces N95 for close contact with COVID-19 suspected pt (3/25/2020)
- Detroit News 734 Henry Ford and 1500 Beaumont HCW are Ill or (+)
- CNN – CDC Reports 9200 HCW Infected (4/15/2020)
- Nature- Antibody Tests Suggest that Coronavirus Infections Vastly Exceed Official Counts
- NEJM LTE Dropplets and Aerosols
- UofM Demonstrates a Containment Option
- Innovative Personal PAPR
- Innovative PAPR Hoods
- 3D Printed PPE
- There are many 3D printer options -> respirators and PAPRs available to consider. I have not validated these but some of them are very interesting and promising. Remember, a PAPR is simply a fan, battery and filter.