Keep it simple: A novel technique for measuring airflow using a wireless patch

Despite the growing use of home sleep testing for obstructive sleep apnea (OSA), there are significant barriers that make it difficult for patients. This study aimed to evaluate a new set of wireless patches for the detection of OSA as compared to polysomnography (PSG) respiratory signals. Safety was also evaluated.

Patients (n = 25; mean age = 51.3; SD = 15.6) undergoing standard PSG evaluation for OSA wore 2 device patches applied on the chest and abdomen to provide surrogates of respiratory effort and derived airflow. Two sets of respiratory data (with common SpO2 and heart rate as a reference from PSG) were created, one from PSG and one from the device patches. Data were scored by a Registered Polysomnographic Technologist. Linear regression analyses and Bland-Altman plots were used to compare the two derived apnea-hypopnea indices (AHI). Bench testing was performed to determine whether the device patch respiratory signal accuracy remained consistent for different body characteristics.

There was a significant correlation for AHI between the device patch and PSG (r = 0.979; P < .001; 95% CI 0.952, 1.00). There were also significant correlations between PSG and the device patch for supine AHI (r = 0.866, P < .001, 95% CI 0.610, 0.965) and nonsupine AHI (r = 0.983; <0.001, 95% CI 0.954, 1.00). No differences in respiratory signal accuracy were found with bench testing comparison groups.

These preliminary results suggest that the device patch may be an effective way to measure respiratory dynamics, including derived airflow, to evaluate OSA. Results show promise as a new innovative method for home sleep testing.