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Published on: April 19, 2024
Performance Evaluation of a Low-Cost Non-Invasive Ventilator during the COVID-19 Pandemic. A Bench Study
Nils Correvon1, Jean-Bernard Michotte1, Olivier Contal1
1School of Health Sciences (HESAV), HES-SO University of Applied Sciences and Arts of Western Switzerland, 1005 Lausanne, Switzerland.
Background:
During the COVID-19 breakout, a global call for low-cost portable ventilators was made following the strong demand for ventilatory support techniques. Among a few development projects, COVIDair non-invasive ventilator was developed and produced in a record time during the critical period of spring 2020.
Objectives:
To evaluate COVIDair performance (i.e., inspiratory trigger delay time, TDT, pressurization time and inspiratory to expiratory time ratio, I:E) on a test bench simulating physiological characteristics of breathing.
Method:
Performance tests were conducted on a breathing simulator (ASL 5000, IngMar Medical™) in two different lung mechanics (i.e., normal and severe restrictive).
Results:
Under normal pulmonary mechanics, the inspiratory TDT is on average between 89.0 (±2.1) and 135.0 (±9.7) ms. In a situation of severe restrictive pulmonary mechanics, the inspiratory TDT is on average between 80 (±3.1) and 99.2 (±5.5) ms. Pressurization time to pre-set inspiratory pressure was on average from 234.6 (±5.5) to 318.6 (±1.9) ms. The absolute difference between the actual I:E cycling measure and the pre-set I:E cycling value ranged from 0.1 to 10.7% on average.
Conclusion:
In normal and severe restrictive pulmonary mechanics scenarios, the performance of COVIDair meets the expected standards for non-invasive ventilators.
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