Verification of the Respiratory Parameters Derived from Impedance Pneumography during Normal and Deep Breathing in Three Body Postures

AbstractRespiratory diseases are a leading cause of death worldwide. The prevalence of sleep apnea, its cardiovascular consequences, postoperative respiratory instability and severe respiratory syndromes further highlight the importance of respiratory monitoring. Typical methods, however, rely on obtrusive nasal cannulas and belts. Impedance pneumography (IP) is a promising bioimpedance application which aims to estimate respiratory parameters from the thorax impedance. Currently, IP configurations require large inter-electrode distances, diminishing its applicability in a wearable context. We propose an IP configuration with 55 mm spacing using our recently presented sensor patch. In a study including 10 healthy subjects, respiratory rate (RR) and flow are estimated in the supine, lateral and prone position. Using time-delay neural network regression, RR errors below 1 bpm, flow correlations of 0.81 and relative flow errors of 38 % with respect to a pneumotachometer reference were achieved. We conclude that high accuracy RR estimation is possible in a 55 mm IP configuration. Respiratory flow can be roughly estimated. Further research combining several biosignals for a more robust, wearable flow estimation is recommended.

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Assessment of calibration methods on impedance pneumography accuracy

Biomedical Engineering / Biomedizinische Technik ◽

10.1515/bmt-2015-0125 ◽

2016 ◽

Vol 61 (6) ◽

Cited By ~ 3

Author(s):

Marcel Młyńczak ◽

Wiktor Niewiadomski ◽

Marek Żyliński ◽

Gerard Cybulski

Keyword(s):

Relative Difference ◽

The Body ◽

Body Posture ◽

Breathing Rate ◽

Deep Breathing ◽

Factors Influencing ◽

Impedance Pneumography ◽

Calibration Methods ◽

Previous Session ◽

Calibration Coefficients

AbstractThe aim was to assess accuracy of tidal volumes (TV) calculated by impedance pneumography (IP), reproducibility of calibration coefficients (CC) between IP and pneumotachometry (PNT), and their relationship with body posture, breathing rate and depth. Fourteen students performed three sessions of 18 series: normal and deep breathing at 6, 10, 15 breaths/min rates, while supine, sitting and standing; 18 CC were calculated for every session. Session 2 was performed 2 months after session 1, session 3 1–3 days after session 2. TV were calculated using full or limited set of CC from current session, in case of sessions 2 and 3 also using CC from session 1 and 2, respectively. When using full set of CC from current session, IP underestimated TV by -3.2%. Using CC from session 2 for session 3 measurements caused decrease of relative difference: -3.9%, from session 1 for session 2: -5.3%; for limited set of CC: -5.0%. The body posture had significant effect on CC. The highest accuracy was obtained when all factors influencing CC were considered. The application of CC related only to body posture may result in shortening of calibration and moderate accuracy loss. Using CC from previous session compromises accuracy moderately.

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Effects of vibration on arm and shoulder muscles in three body postures

European Journal of Applied Physiology and Occupational Physiology ◽

10.1007/bf02388323 ◽

1989 ◽

Vol 59 (4) ◽

pp. 243-248 ◽

Cited By ~ 19

Author(s):

W. Rohmert ◽

H. Wos ◽

S. Norlander ◽

R. Helbig

Keyword(s):

Body Postures ◽

Shoulder Muscles ◽

Three Body

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Dual-Lead 55 mm Impedance Pneumography

Current Directions in Biomedical Engineering ◽

10.1515/cdbme-2020-3052 ◽

2020 ◽

Vol 6 (3) ◽

pp. 205-208

Author(s):

Michael Klum ◽

Mike Urban ◽

Alexandru-Gabriel Pielmus ◽

Reinhold Orglmeister

Keyword(s):

Subject Position ◽

Respiratory Monitoring ◽

Electrode Spacing ◽

Estimation Errors ◽

Impedance Pneumography ◽

Respiratory Parameters ◽

High Prevalence ◽

Respiratory Signal ◽

Dual Lead ◽

Relative Errors

AbstractIn recent years, respiratory monitoring has gained attention due to the high prevalence and severe consequences of sleep apnea, post-anesthesia respiratory instability and respiratory diseases. Nevertheless, respiratory monitoring oftentimes relies on obtrusive masks and belts, which are unsuitable for wearable, long-term monitoring. Impedance pneumography (IP) is a bioimpedance method aiming to assess respiratory parameters unobtrusively. However, most IP configurations require far-spaced electrodes. Based on our recent work on wearable IP, we propose a dual-lead, wearable IP setup with 55 mm electrode spacing to estimate respiratory flow and rate (RR). Using our recently presented multimodal patch stethoscope as well as commercial systems, we conducted a study including 10 healthy subjects which were recorded in the supine, lateral and prone position. Using time-delay neural networks, we achieved RR estimation errors below 0.6 breaths per minute and flow correlations of 0.88 with relative errors of 25 % to a pneumotachometer reference. We conclude that dual-lead IP increases the performance of respiratory signal estimation compared to a single lead and recommend research in the area of subject position dependency and movement artefacts.

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