JMIR Publications

ABSTRACT

Background:

Obstructive Sleep Apnoea (OSA) is a condition where during sleep a person’s airway becomes obstructive, disturbing their sleep. People with OSA have a higher risk of developing heart problems. OSA is commonly treated with a Positive Airway Pressure (PAP) therapy device, which is used during sleep. The PAP therapy setup provides a good opportunity to monitor the heart health of people with OSA.

Objective:

The aim of this study was to develop a simple, low-cost device to monitor the Heart Rate (HR) of people with Obstructive Sleep Apnoea (OSA) during Positive Airway Pressure (PAP) therapy. This device was then tested on a small group of participants to investigate the feasibility of the device.

Methods:

A low-cost and simple device to monitor HR was created by attaching a gyroscope to a PAP mask, thus integrating the HR monitoring into the PAP therapy. The gyroscope signals were then analysed to detect heartbeats and a Kalman Filter was used to produce a more accurate and consistent HR signal. In this paper 19 healthy participants wore the modified PAP mask while the mask was connected to a PAP device. Participants lay in three common sleeping positions and underwent two different PAP therapy modes to determine if these affected the accuracy of the HR estimation.

Results:

Prior to the PAP device being turned on the median HR error was < 5BPM, although the HR estimation error increased when participants lay on their side compared with lying on their back. Using the different PAP therapy modes did not significantly increase the HR error.

Conclusions:

These results show that monitoring HR from gyroscope signals in a PAP mask is possible during PAP therapy for different sleeping positions and PAP therapy modes, suggesting long term HR monitoring of OSA during PAP therapy may be possible.