Audrey Dang1, Brent Williams1, William D Warsing2, Michael Noone3, Alexander P Isakov4, David K Tan2,5, Stephen Y Liang5,6. 1. Center for Aerosol Science and Engineering, Department of Energy, Environmental, and Chemical Engineering, Washington University in St. Louis, MO, USA. 2. Abbott Emergency Medical Services, American Medical Response, St. Louis, MO, USA. 3. Los Angeles County Emergency Medical Services, Los Angeles, CA, USA. 4. Department of Emergency Medicine, Emory University School of Medicine, Atlanta, GA, USA. 5. Department of Emergency Medicine, Washington University School of Medicine, St. Louis, MO, USA. 6. Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA.
Abstract
OBJECTIVE: Stretcher transport isolators provide mobile, high-level biocontainment outside the hospital for patients with highly infectious diseases, such as Ebola virus disease. Air quality within this confined space may pose human health risks. METHODS: Ambient air temperature, relative humidity, and CO2 concentration were monitored within an isolator during 2 operational exercises with healthy volunteers, including a ground transport exercise of approximately 257 miles. In addition, failure of the blower unit providing ambient air to the isolator was simulated. A simple compartmental model was developed to predict CO2 and H2O concentrations within the isolator. RESULTS: In both exercises, CO2 and H2O concentrations were elevated inside the isolator, reaching steady-state values of 4434 ± 1013 ppm CO2 and 22 ± 2 mbar H2O in the first exercise and 3038 ± 269 ppm CO2 and 20 ± 1 mbar H2O in the second exercise. When blower failure was simulated, CO2 concentration exceeded 10 000 ppm within 8 minutes. A simple compartmental model predicted CO2 and H2O concentrations by accounting for human emissions and blower air exchange. CONCLUSIONS: Attention to air quality within stretcher transport isolators (including adequate ventilation to prevent accumulation of CO2 and other bioeffluents) is needed to optimize patient safety.
OBJECTIVE: Stretcher transport isolators provide mobile, high-level biocontainment outside the hospital for patients with highly infectious diseases, such as Ebola virus disease. Air quality within this confined space may pose human health risks. METHODS: Ambient air temperature, relative humidity, and CO2 concentration were monitored within an isolator during 2 operational exercises with healthy volunteers, including a ground transport exercise of approximately 257 miles. In addition, failure of the blower unit providing ambient air to the isolator was simulated. A simple compartmental model was developed to predict CO2 and H2O concentrations within the isolator. RESULTS: In both exercises, CO2 and H2O concentrations were elevated inside the isolator, reaching steady-state values of 4434 ± 1013 ppm CO2 and 22 ± 2 mbar H2O in the first exercise and 3038 ± 269 ppm CO2 and 20 ± 1 mbar H2O in the second exercise. When blower failure was simulated, CO2 concentration exceeded 10 000 ppm within 8 minutes. A simple compartmental model predicted CO2 and H2O concentrations by accounting for human emissions and blower air exchange. CONCLUSIONS: Attention to air quality within stretcher transport isolators (including adequate ventilation to prevent accumulation of CO2 and other bioeffluents) is needed to optimize patient safety.
Entities:
Keywords:
Ebola virus disease; air quality; biocontainment; emergency medical services; transport isolator
Authors: S Schilling; P Follin; B Jarhall; A Tegnell; M Lastilla; B Bannister; F Maria Fusco; R Biselli; H-R Brodt; V Puro Journal: Clin Microbiol Infect Date: 2009-06-12 Impact factor: 8.067
Authors: Paolo Carrer; Eduardo de Oliveira Fernandes; Hugo Santos; Otto Hänninen; Stylianos Kephalopoulos; Pawel Wargocki Journal: Int J Environ Res Public Health Date: 2018-06-28 Impact factor: 3.390
Authors: Edward D Nicol; Stephen Mepham; Jonathan Naylor; Ian Mollan; Matthew Adam; Joanna d'Arcy; Philip Gillen; Emma Vincent; Belinda Mollan; David Mulvaney; Andrew Green; Michael Jacobs Journal: Emerg Infect Dis Date: 2019-01-17 Impact factor: 6.883