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Updated: Nov 2, 2025

Normothermic Negative Pressure Ventilation Ex Situ Lung Perfusion: Evaluation of Lung Function and Metabolism
Published on: February 14, 2022
Repurposing CPAP machines as stripped-down ventilators
J Nguyen1, K Kesper2, G Kräling3
1Faculty of Physics and Material Sciences Centre, Philipps-Universität Marburg, Marburg, Germany. johnny.nguyen@physik.uni-marburg.de.
Abstract:
The worldwide shortage of medical-grade ventilators is a well-known issue, that has become one of the central topics during the COVID-19 pandemic. Given that these machines are expensive and have long lead times, one approach is to vacate them for patients in critical conditions while patients with mild to moderate symptoms are treated with stripped-down ventilators. We propose a mass-producible solution that can create such ventilators with minimum effort. The central part is a module that can be attached to CPAP machines and repurpose them as low-pressure ventilators. Here, we describe the concept and first measurements which underline the potential of our solution. Our approach may serve as a starting point for open-access ventilator technologies.
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