LAUSR

The SARS-CoV-2 pandemic is straining healthcare systems worldwide, and a global ventilator shortage is fueling the dire situation. As a response, the MIT E-Vent Team (S1) manufactured a scalable ventilator prototype for mass production and demonstrated basic clinical feasibility. MIT E-Vent engineering information and capabilities, but also missing safety features are provided on the MIT E-Vent website (https ://e-vent.mit.edu/) and in the attachments (Fig. 1a, S2). Pressure-based alarms were implemented including in the `Spiro Wave’ device that is based on the MIT E-vent and was just authorized for emergency use by the US FDA. In brief, the MIT E-Vent houses a manual resuscitator, an external compression mechanism, and a control system for adjusting tidal volumes, inspiration-to-expiration ratio, and respiratory rate (Fig. 1a, S3, S4). The MIT E-Vent is equipped with a pressure relief and a positive end-expiratory pressure (PEEP) valve. It delivers unassisted (Fig. 1b) and assisted (not shown) volume control ventilation (VCV). As a proof of concept, a pig was ventilated with the MIT E-Vent or a standard mechanical ventilator (SMV) at distinct settings and arterial blood gases, ventilator waveforms, and flowvolume loops were obtained. The MIT E-Vent performed similar to a SMV at identical respiratory settings. After 36 h of usage including at high demand settings (TV 600 cc, RR 30, PEEP 20), no signs of device failure were noted (S5). Tidal volume delivery MIT E-Vent waveforms showed a smooth tidal volume delivery (Fig. 1b). It revealed similar flow-volume loops when compared to manual ventilation using a manual resuscitator (Fig. 1c).