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Updated: Sep 12, 2025

Ex Vivo Porcine Experimental Model for Studying and Teaching Lung Mechanics
Published on: April 19, 2024
Performance assessment of a ventilator developed for emergency use in a resource-constrained ICU setting during the
Sergio Sánchez-Gambetta1, Giuliana Arrunategui-Salas1,2, Juan L Barrios-Morocho1
1Department of Engineering, Pontificia Universidad Católica del Peru, Lima, Peru.
Background:
The Masi mechanical ventilator was developed in Peru, designed and manufactured as a rapid-response to the healthcare emergency. Its promising pre-clinical and clinical results allowed it to be approved by the national regulatory authority to be used during the emergency. The key features of Masi are its low manufacturing cost, low dependence on a supply of high volumes of oxygen, low oxygen consumption, and flexibility between non-invasive and invasive ventilation. While Masi lacks some of the advanced features found in commercial ICU ventilators, it was specifically designed for short-term use in resource-limited and high-demand situations as an alternative when conventional devices were unavailable. This study evaluates the survival rate in intubated COVID-19 patients ventilated with Masi as compared to other conventional ventilators.
Methods:
This retrospective study was conducted in the ICU of a reference hospital in Lima, Peru, between January and August 2021. Medical records were reviewed for 77 adult patients with suspected or confirmed COVID-19 who required invasive mechanical ventilation. Among them, 42 patients were ventilated with Masi and 35 with commercially available ventilators. Clinical characteristics, laboratory findings, respiratory parameters, and survival outcomes were collected and analyzed.
Results:
The survival rate and the relevant parameters observed in patients supported with Masi and commercial ventilators were comparable, despite the device limitations and the resource-constrained conditions.
Conclusions:
Masi ventilator was functional and provided essential ventilatory support during the healthcare emergency.
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