The Apnea Risk Evaluation System (ARES™) integrates physiological data acquired in-home with clinical history and anthropomorphic data to determine the presence and severity of Obstructive Sleep Apnea (OSA). ARES™ has been cleared for use by the United States Food and Drug Administration (FDA), and is ISO 13485 certified for Europe and Canada.
ARES™ Home Sleep test Device integrates:
A sleep-wearable, wireless physiological recorder worn on the forehead that acquires and stores up to 3 nights of nocturnal data. ARES™ measures blood oxygen saturation (SpO2) and pulse rate (reflectance pulse oximetry), airflow (by nasal cannula connected to a pressure transducer), snoring levels (calibrated acoustic microphone), head movement and head position (accelerometers). When worn in the home, the ARES™ provides a better profile of the patient’s breathing during sleep in his/her normal environment. Audio and visual indicators notify the user when the ARES™ requires adjustment, thus increasing reliability of the device in the home. The small size of ARES™ allows it to be comfortably worn in all sleep positions.
A validated predictor of OSA risk (those in need of a sleep study based on a predicted apnea/hypopnea index > 5 events/hour) and OSA severity (i.e., minimal, mild, moderate or severe) using responses to questions about body type, symptoms of daytime drowsiness, snoring, and other sleep-related characteristics or health conditions associated with OSA. The results can be used to rapidly screen large populations to determine a prior probability of obstructive sleep apnea (OSA). The results are also used to supplement the physiological data obtained in the ARES Sleep Apnea Study.
ARES Sleep Study Signals and Measurements
ARES captures blood oxygen saturation and pulse rate using reflectance pulse oximetry. The ARES oximeter was designed specifically for the diagnosis of OSA, which involves the detections and quantification of brief desaturations and resaturations. It measures oxyhemoglobin saturation in 0.1% increments rather than the typical 1%, which allows identification of small but important changes in saturation.
Airflow (nasal pressure) – Changes in air pressure are measured with a pressure transducer connected to the nasal opening via a nasal cannula. Decreases and increases in flow of 50% or more are automatically identified and marked as hypopneas and cessations of airflow for at least 10 seconds are marked as apneas.
Pulse Rate – ARES uses reflectance pulse oximetry to measure pulse rate. Limited smoothing of pulse rate signal increases capability of ARES Insight software to recognize brief changes in pulse rate (e.g., Brady-tachycardias). These changes in pulse rate are recognized markers of arousal.
Snoring – Snoring is recorded with a calibrated acoustic microphone so that the level of loudness can be precisely quantified. Changes in snoring patterns and crescendo snoring are automatically recognized and used as markers of a respiratory-related arousals.
Head Position/Movement – Head position indicates the position of the pharynx and is used to determine the positionality of obstructive events. Understanding the influence of position on the severity of the OSA is useful in making treatment decisions. Head movement is measured using accelerometers similar to those used for actigraphy. Head movement is a unique signal identified by ARES as a marker of respiratory related arousal.
Sleep/Wake – ARES measures sleep behaviorally by combining the detection of subtle movements through actigraphy, with variability of the airflow signal and recognition of snoring.
REM/NREM – ARES distinguishes REM from NREM using EEG, EOG and EMG signals derived from two electrodes placed at FP1 and FP2 on the forehead.
Apnea/Hypopnea Index (AHI) – ARES determines AHI by adding the number of apneas and hypopneas per hour, where there is a 4% oxygen desaturation.
Respiratory Disturbance Index (RDI) – ARES measures RDI by adding the number of apneas and hypopneas per hour, where the hypopneas require a 1% oxygen desaturation/resaturation and at least one behavioral arousal indicator.