Device to monitor quiet breath of CRD patients

Abstract

Rising pollution worldwide is a major reason for increasing number of patients of chronic respiratory diseases (CRD) like Asthma. CRD are irreversible, can only be managed through proper care and medication. Spirometry is the only known test for finding the functional health of lungs but 90% of CRD patients fail to perform the test. Moreover, Spirometry is non reproducible and difference of about 20% were reported over two tests in reasonably close time instance. This is a painful test as a patient has to make full capacity forced exhalation without coughing, a rare possibility with CRD patients. Device prototype tested here is S-MASK, envisioned to assess the level of breathing discomfort experienced by a CRD patient. S-MASK is a compact and sensitive device that can capture the normal or quiet breath. Design objective of S-MASK is to develop a device that can be used on regular basis to assess the wellness and relative/absolute relief from CRD symptoms.The design of S-MASK and its validation is presented in this paper. Breath rate computed from the device has R-squared = 0.9 and p-Value < 10−4 with respect to manually observed values. Breath samples collected using S-MASK found to have µ = 0.308 Hz and σ = 0.073 Hz which corresponds to µ = 18.66 bpm (breath per minute) and σ = 4.38 bpm. These values are significantly close to manually observed breath rate i.e. μ = 17.8 bpm and σ = 4.22 bpm.These results are statistically significant to validate the capabilities of S-MASK to capture the quite breath and identify the rate. S-MASK is device of its kind that computes the breath rate using frequency spectrum.