The eSpiro Ventilator: An Open-Source Response to a Worldwide Pandemic

Objective: To address the issue of ventilator shortages, our group (eSpiro Network) developed a freely replicable, open-source hardware ventilator. Design: We performed a bench study. Setting: Dedicated research room as part of an ICU affiliated to a university hospital. Subjects: We set the lung model with three conditions of resistance and linear compliance for mimicking different respiratory mechanics of representative intensive care unit (ICU) patients. Interventions: The performance of the device was tested using the ASL5000 lung model. Measurements and Main Results: Twenty-seven conditions were tested. All the measurements fell within the +/- 10% limits for the tidal volume (V-T). The volume error was influenced by the mechanical condition (p = 5.9 x 10(-15)) and the PEEP level (P = 1.1 x 10(-12)) but the clinical significance of this finding is likely meaningless (maximum -34 mL in the error). The PEEP error was not influenced by the mechanical condition (p = 0.25). Our experimental results demonstrate that the eSpiro ventilator is reliable to deliver V-T and PEEP accurately in various respiratory mechanics conditions. Conclusions: We report a low-cost, easy-to-build ventilator, which is reliable to deliver V-T and PEEP in passive invasive mechanical ventilation.