Sleep Disordered Breathing

We are introducing a non-contact respiratory monitoring method that can be used in Sleep Disordered Breathing (SDB) studies to significantly broaden our understanding of over-night breathing behaviors

Sleep disordered breathing (SDB) in children is considered by pediatricians to be a public health problem with serious consequences such as decreased cognitive function, poor school performance, daytime sleepiness and increased cardiovascular risk. Current diagnosis of SDB is performed in hospital sleep laboratories by monitoring patients with numerous cardiorespiratory sensors attached at various positions on the patient’s body. This obtrusive form of monitoring is very inconvenient for patients and require tremendous amount of attention from technicians to ensure study quality. Children, especially, tolerate the study very poorly; often removing oral or nasal tubes, having trouble sleeping, necessitating repeat investigations which can be time consuming, costly, and stressful for children.

Sleep Disordered Breathing (SDB)
Nasal monitoring and thermistors
Respiratory belts for breathing rate

There are several existing respiratory diagnostic devices that are used in SDB sutides for children. These primarily include: thermistors (which are essentially temperature sensitive stickers applied to the child’s face) and respiratory belts that capture chest movement to measure breathing rate. While these solutions provide some form of insight into a child’s breathing behaviors during sleep, the measurements are limited to respiratory rate – which has to be interpreted by clinicians to determine possible respiratory ailments. This means that current overnight monitoring techniques cannot accurately measure a patient’s natural breathing behaviors, breathing volume, and natural distribution between oral and nasal breathing remotely, all of which are important information for SDB studies. The following image sequence and video provide a demonstration of the technology applied to sleep-related breathing behaviors.

Sleep-based Breathing Analysis: Dense exhale flow behavior tracked and extracted through our solution. Exhaled CO2 is measured as a function of flow indicated by the color gradient computed from flow magnitude. This allows us to estimate respiratory rate, natural flow behaviors, volume, oral-nasal breathing, and identify patterns related to specific conditions.

The visualization of the exhale flow behaviors is isolated using our software tracking algorithms that provide real-time video analysis of breathing behaviors. Colors within the tracked exhale represent the magnitude of the flow within specific regions, providing detailed analysis of the behavior. This provides the first step in our processing pipeline for the generation of detailed respiratory behavior from thermal CO2 exhale detection. This data is then used to generate quantitative metrics such as breathing rate, flow, volume, and other new metrics we introduce such as breathing strength, nose-to-mouth distribution, all obtained through natural breathing (no tubes, or wires).