Low latency breathing frequency detection and monitoring on a personal computer

Abstract

We demonstrate a low latency respiratory/breathing frequency detection system that is fast (<5 ms), easy to operate, requires no batteries or external power supply and operates fully via computer-standard USB connection. Exercises in controlling ones breathing frequency, usually referred to as paced-breathing exercises, have shown positive effects in treating pulmonary diseases, cardiovascular diseases and stress/anxiety-related disorders. We developed a breathing frequency detection system which uses two pairs of microphones to detect exhalation activity, eliminate noise from the environment and stream the recording data via USB connection to a personal computer. It showed 97.1% reliability (10 subjects) when monitoring breathing activity in non-guided free breathing and 100% reliability (10 subjects) when monitoring breathing activity during interactive paced-breathing exercises. We also evaluated the breathing frequency detection systems noise elimination functionality which showed a reduction of 84.2 dB for stationary (white noise) and a reduction of 79.3 dB for non-stationary (hands clapping) noise.

Keywords::

• Respiration
• breathing frequency detection
• respiratory sinus arrhythmia
• heart rate variability
• asthma
• hypertension

Acknowledgements

This research was supported by the European Union through the European Social Fund and was coordinated by the Public Agency for Technology of the Republic of Slovenia (TIA) according to the program of Human Resources Development 2007–2013. We would also like to thank Professor Damijan Miklavčič of the Faculty of Electrical Engineering, Ljubljana Slovenia, for his kind help and valuable discussions regarding this research.

Declaration of interest

Matevž Leskovšek, partner at Zdrav dih d.o.o., is author and owner of patents WO2010/005401 (pending), SI200900171, SI200800175. This technology can be used freely for non-commercial research purposes only.