Differential ventilation using flow control valves as a potential bridge to full ventilatory support during the COVID-19 crisis

Matthew Levin; Martin D Chen; Anjan Shah; Ronak Shah; George Zhou; Erica Kane; Garrett Burnett; Shams Ranginwala; Jonathan Madek; Christopher Gidiscin; Chang Park; Daniel Katz; Benjamin Salter; Roopa Kohli-Seth; James B Eisenkraft; Suzan Uysal; Michael McCarry; Andrew B Leibowitz; David L Reich

The copyright holder for this preprint (which was not peer-reviewed) is the . https://doi.org/10.1101/2020.04.14.20053587 doi: medRxiv preprint Panel: Study 1. At the start of the study, tidal volumes fell for both patients, and peak airway pressures rose. Both parameters then stabilized. The red line indicates when the flow control valve for patient A was further opened by ¾ of a turn. The tidal volume and peak airway pressure for patient A subsequently rose, while the tidal volume and peak airway pressure for patient B remained unchanged. Right Panel: Study 2. Tidal volume fell and peak airway pressure rose, as in study 1. The red line indicates valve adjustment for Patient B. In this case, the valve was closed slightly and then opened again to allow slightly more flow. Tidal volume for Patient B remained nearly the same while peak airway pressure rose.