A prototype of wearable respiration biofeedback platform and its preliminary evaluation on cardiovascular variability

This paper introduced the development of a prototype wearable respiration biofeedback platform and made a preliminary evaluation of its effects on cardiovascular system. The biofeedback platform consisted of three parts: a shirt with multiple wearable sensors embedded in to acquire necessary physiological signals such as ECG, rib cage and abdomen movement, radial artery pulse, PCG, PPG,temperature, posture and activities etc, an NI 14bits USB data acquisition card USB-6009 to acquire multiple parameters simultaneously at a sample rate of 1000Hz/s, and a notebook PC with LABVIEW8.2 software to generate the audiovisual guiding signals to the user based on the detected breathing pattern and special algorithms. With this platform, a preliminary experiment was done to evaluate its performance. 16 volunteers were recruited in this experiment and cardiovascular variability under guided breathing was chosen to be analyzed. It was shown that this prototype platform with audiovisual biofeedback technology to guide the user's breathing movement was effective, it was easy for the user to do the desired breathing maneuver and got wanted cardiovascular and cardiopulmonary interaction to make beneficial effects. User-specific guiding waveform is especially useful for the user to learn and follow the breathing maneuvers at the initial stage. Increased heart rate variability and PWTT variability were observed during this breathing biofeedback procedure. Prolonged baseline change of PWTT was also observed with the decreased breathing rate in some volunteers. Further work is still needed to use this platform to study the mechanism of cardiopulmonary interaction, and a wearable mobile biofeedback system based on PDA also needs to be developed.