Preliminary Assessment of a Flexible Multi-Sensor Wearable System Based on Fiber Bragg Gratings for Respiratory Monitoring of Hemiplegic Patients

Abstract

Respiratory diseases are common in post-stroke hemiplegic patients and represent a major social problem as they worsen the quality of life and reduce the life span. As a consequence, being able to monitor respiratory parameters such as the respiratory rate (RR) and assess the presence of respiratory asynchronies could be of paramount importance to define hemiplegics’ health status. Moreover, RR is a useful parameter to investigate the level of fatigue and distress that these patients undergo during rehabilitation processes. Although motion capture systems and flowmeters are the leading instruments for respiratory pattern evaluation, smart wearable systems are gaining ever more acceptance since they allow continuous monitoring by detecting chest wall breathing displacements, ensuring reduced costs and no need for dedicated spaces. Among other sensing technologies, fiber Bragg grating (FBG) sensors have emerged thanks to their high sensitivity to strain, lightness, and multiplexing capability. In this work, a wearable system composed of four flexible dumbbell-shaped sensing modules is proposed for respiratory monitoring in hemiplegic patients. The system is light and easy to wear and can be adapted to any anthropometry thanks to the modular anchoring system. Its feasibility assessment in RR evaluation was performed on seven hemiplegic volunteers in eupnea and tachypnea breathing conditions. In addition, an explorative investigation was conducted to assess the system’s ability to detect asynchronies between torso compartments. The good results suggest that this device could be a useful instrument to support clinicians and operators in hemiplegic patients’ management.

Breathing Chest Wall Kinematics Assessment through a Single Digital Camera: A Feasibility Study

“…Thus, these signals were used to estimate time-related respiratory parameters and respiratory asynchronies. Results show that the proposed non-contact system allows for the estimation of f R values and temporal parameters (i.e., T i , T e , and T tot ) that are comparable with those of wearable systems (e.g., a bias of −0.2 bpm for f R and 0.01 s for T tot as reported in [ 15 , 43 ]) as well as with those of non-contact technologies (e.g., LOAs of ±5 bpm and of ±3.4 bpm for f R , as reported in [ 22 , 44 ]). Considering all the estimated time-related respiratory parameters, we achieved comparable results in terms of median and IQR with those obtained in [ 24 ] (e.g., a median of 13.43 bpm in our work and a median of 16.0 bpm in Tamiya et al).…”

“…Contact-based or contactless technologies can independently detect breathing patterns and thoraco-abdominal motions. Among the contact-based techniques, wearable systems based on different types of sensors (e.g., piezoresistive, capacitive, and fiber optic sensors) and their appropriate placement on the subject’s torso have been employed [ 14 , 15 ]. Respiratory inductance plethysmography (RIP) is the most used contact-based system to quantify chest wall movements.…”