Low-Cost Open-Source Device to Measure Maximal Inspiratory and Expiratory Pressures.

Aymerich C, Rodríguez-Lázaro M, Solana G, Farré R, Otero J.

Front Physiol. 2021 Aug 26;12:719372. doi: 10.3389/fphys.2021.719372

 

ABSTRACT

Background: The measurement of maximal inspiratory (MIP) and maximal expiratory (MEP) pressures is a widely used technique to non-invasively evaluate respiratory muscle strength in clinical practice. The commercial devices that perform this test range from whole body plethysmographs to portable spirometers, both expensive and include a wide range of other respiratory tests. Given that a portable, low-cost, and specific option for MIP and MEP measuring device is not currently available in the market. Methods: A high-performance and easy-to-build prototype has been developed and the detailed technical information to easily reproduce it is freely released. A novel device is based on an Arduino microcontroller with a digital display, an integrated pressure transducer, and three-dimensional (3D) printed enclosure (total retail cost €80). Results: The validation of the device was performed by comparison with a laboratory reference setting, and results showed accuracy within ±1%. Conclusions: As the device design is available according to the open-source hardware approach, measuring MIP/MEP can greatly facilitate easily available point-of-care devices for the monitoring of patients and, most important, for making this lung function measurement tool affordable to users in low- and middle-income countries.