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It is unclear whether either chest compressions or defibrillation is an aerosol generating event and whether there is significant transmission risk for resuscitators.
pearl- Keith Couper, Sian Taylor-Phillips, Amy Grove, Karoline Freeman, Osemeke Osokogu, Rachel Court, Amin Mehrabian, Peter T Morley, Jerry P Nolan, Jasmeet Soar, and Gavin D Perkins.
- Warwick Medical School, University of Warwick, Coventry, UK; Critical Care, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK.
- Resuscitation. 2020 Jun 1; 151: 59-66.
BackgroundThere may be a risk of COVID-19 transmission to rescuers delivering treatment for cardiac arrest. The aim of this review was to identify the potential risk of transmission associated with key interventions (chest compressions, defibrillation, cardiopulmonary resuscitation) to inform international treatment recommendations.MethodsWe undertook a systematic review comprising three questions: (1) aerosol generation associated with key interventions; (2) risk of airborne infection transmission associated with key interventions; and (3) the effect of different personal protective equipment strategies. We searched MEDLINE, Embase, Cochrane Central Register of Controlled Trials, and the World Health Organization COVID-19 database on 24th March 2020. Eligibility criteria were developed individually for each question. We assessed risk of bias for individual studies, and used the GRADE process to assess evidence certainty by outcome.ResultsWe included eleven studies: two cohort studies, one case control study, five case reports, and three manikin randomised controlled trials. We did not find any direct evidence that chest compressions or defibrillation either are or are not associated with aerosol generation or transmission of infection. Data from manikin studies indicates that donning of personal protective equipment delays treatment delivery. Studies provided only indirect evidence, with no study describing patients with COVID-19. Evidence certainty was low or very low for all outcomes.ConclusionIt is uncertain whether chest compressions or defibrillation cause aerosol generation or transmission of COVID-19 to rescuers. There is very limited evidence and a rapid need for further studies. Review registration: PROSPERO CRD42020175594.Copyright © 2020. Published by Elsevier B.V.
This article appears in the collection: Anaesthesiology, Personal Protective Equipment (PPE) and COVID.
Notes
Public Health England's 'New and Emerging Respiratory Virus Threats Advisory Group (NERVTAG)' concluded:
It is biologically plausible that chest compressions could generate an aerosol, but only in the same way that an exhalation breath would do. No other mechanism exists to generate an aerosol other than compressing the chest and an expiration breath, much like a cough, is not currently recognised as a high-risk event or an AGP.” NERVTAG also stated that it “does not consider that the evidence supports chest compressions or defibrillation being procedures that are associated with a significantly increased risk of transmission of acute respiratory infections.”
Daniel Jolley
Also worth considering, is the impact that CPR and external compressions may have on undermining the effective protection of PPE, given that CPR is a uniquely dynamic and physical activity compared to most medical procedures.
Using simulation studies, Hwang et al. have already brought into question the effectiveness of N95 masks during CPR:
N95 respirator masks may not provide adequate protection during chest compressions, even when resuscitators have passed quantitative fit testing.