title: Estimates of the demand for mechanical ventilation in the United States during an influenza pandemic.
abstract: An outbreak in China in April 2013 of human illnesses due to avian influenza A(H7N9) virus provided reason for US public health officials to revisit existing national pandemic response plans. We built a spreadsheet model to examine the potential demand for invasive mechanical ventilation (excluding "rescue therapy" ventilation). We considered scenarios of either 20% or 30% gross influenza clinical attack rate (CAR), with a "low severity" scenario with case fatality rates (CFR) of 0.05%-0.1%, or a "high severity" scenario (CFR: 0.25%-0.5%). We used rates-of-influenza-related illness to calculate the numbers of potential clinical cases, hospitalizations, admissions to intensive care units, and need for mechanical ventilation. We assumed 10 days ventilator use per ventilated patient, 13% of total ventilator demand will occur at peak, and a 33.7% weighted average mortality risk while on a ventilator. At peak, for a 20% CAR, low severity scenario, an additional 7000 to 11,000 ventilators will be needed, averting a pandemic total of 35,000 to 55,000 deaths. A 30% CAR, high severity scenario, will need approximately 35,000 to 60,500 additional ventilators, averting a pandemic total 178,000 to 308,000 deaths. Estimates of deaths averted may not be realized because successful ventilation also depends on sufficient numbers of suitably trained staff, needed supplies (eg, drugs, reliable oxygen sources, suction apparatus, circuits, and monitoring equipment) and timely ability to match access to ventilators with critically ill cases. There is a clear challenge to plan and prepare to meet demands for mechanical ventilators for a future severe pandemic.
authors: Division of Preparedness and Emerging Infections, National Center for Emerging and Zoonotic Infectious Diseases.
authors: Martin I
authors: MI
authors: Meltzer
authors: Division of Strategic National Stockpile, Office of Public Health Preparedness and Response, Centers for Disease Control and Prevention, Atlanta, Georgia.
authors: Anita
authors: A
authors: Patel
authors: Formerly, GAP Solutions Incorporated, Contracted to the Office of the Assistant Secretary for Preparedness and Response.
authors: Adebola
authors: A
authors: Ajao
authors: Division of Medical Countermeasure Strategy and Requirements, Office of the Assistant Secretary for Preparedness and Response, US Department of Health and Human Services, Washington, D.C.
authors: Scott V
authors: SV
authors: Nystrom
authors: Influenza Coordination Unit, Office of Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia.
authors: Lisa M
authors: LM
authors: Koonin
mesh_terms: D004189:Disaster Planning / Q000379:methods*; D006801:Humans; D064766:Influenza A Virus, H7N9 Subtype / Q000472:pathogenicity; D007251:Influenza, Human / Q000453:epidemiology / Q000401:mortality / Q000628:therapy*; D007362:Intensive Care Units / Q000600:supply & distribution; D008962:Models, Theoretical; D058873:Pandemics; D011634:Public Health / Q000379:methods; D012121:Respiration, Artificial / Q000295:instrumentation; D014481:United States / Q000453:epidemiology; D012122:Ventilators, Mechanical / Q000600:supply & distribution*
keywords: demand; influenza pandemic; ventilation; ventilator