A Portable Low-Cost Device for Respiratory Rate Monitoring in COVID-19, Persistent Post-COVID and Other Severe Respiratory Syndromes

The aim of this work is to describe a portable instrument able to evaluate the respiratory rate. Such device may be a useful tool in telemedicine and home care applications. After a detailed description of the device, an in vitro study showed a significant correlation (p < 0.0001), showing a positive association with R2 = 1, and no errors in the studied range. In vivo tests of the portable device in the identification of respiratory changes in patients with Persistent Post-COVID showed results in close agreement with the physiology, and adequate diagnostic accuracy (area under the receiver operating characteristic curve of 0.732, sensibility of 0.70, and specificity of 0.80). These results confirms the high scientific and clinical potential of this system in home care and telemedicine applications.