Non-contact real-time estimation of intrapulmonary pressure and tidal volume for chronic heart failure patients

Abstract

Long-term continuous patient monitoring is required in many health systems for monitoring and analytical diagnosing purposes. It has been recognized that these types of monitoring systems have shortcomings related to patient comfort and/or functionality. Non-contact monitoring systems have been developed to address some of these shortcomings. One of such systems is non-contact physiological vital signs assessments for Chronic Heart Failure (CHF) patients. This paper presents a novel pulmonary ventilation model that defines the relationship between the intrapulmonary pressure and the chest displacement. A novel intrapulmonary pressure and tidal volume estimation algorithm is also proposed. A database consisting of twenty CHF patients with New York Heart Association (NYHA) Heart Failure Classification Class II & III; whose underwent full Polysomnography (PSG) analysis for diagnosis of sleep apnea, disordered sleep, or both, was selected for the verification of the proposed model and algorithm. The proposed algorithm analyzes the non-contact sensor data and estimate the patient's intrapulmonary pressure and tidal volume. The output of the algorithm is compared with the gold-standard PSG recordings. Across all twenty CHF patients' recordings with mean recorded sleep duration of 7.76 hours, the tidal volume estimation median accuracy achieved 83.13% with a median error of 57.32 milliliters. A potential application would be non-contact continuous monitoring of intrapulmonary pressure and tidal volume during sleep in the home.

Doppler Radar-Based Non-Contact Health Monitoring for Obstructive Sleep Apnea Diagnosis: A Comprehensive Review

“…A pulmonary ventilation mathematical model and algorithm that defines the relationship between the intrapulmonary pressure and the chest displacement has also been proposed [43]. The mathematical model and algorithm estimate the tidal volume from the non-contact Doppler radar I/Q signals from a set of 24 chronic heart failure (CHF) patients with median sleep duration of 7.76 h. The tidal volume estimation median accuracy achieved is 83.13%, with a median error of 57.32 milliliters.…”

“…2016 [43] Tidal volume Up to 83.13% accuracy with error up to 57.32 milliliters. 2013-2016 [43][44][45] Sleep/wake pattern Up to 69% for awake state and 88% for sleep stages.…”

Vital Signs Monitoring Based on Interferometric Fiber Optic Sensors

“…Obstructive sleep apnea is a common and potentially fatal sleep disorder that affects at least 4% of men and 2% of women worldwide [60]. Respiratory volume monitors can provide real-time RR and respiration volume information, which are significant indicators for the diagnosis of obstructive sleep apnea [61].…”

Human Vital Signs Detection Methods and Potential Using Radars: A Review

“…The radar data can, therefore, be used to estimate the tidal volume based on this relationship. Furthermore, the authors in [121] proposed a mathematical model relating the intrapulmonary pressure and the chest-wall displacement. Then, the tidal volume is estimated using the baseband signals of the Doppler radar.…”