{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,26]],"date-time":"2026-04-26T12:35:54Z","timestamp":1777206954028,"version":"3.51.4"},"reference-count":32,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2019,3,7]],"date-time":"2019-03-07T00:00:00Z","timestamp":1551916800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002809","name":"Generalitat de Catalunya","doi-asserted-by":"publisher","award":["DPI2015-68820-R (MINECO\/FEDER), through the CERCA Programme, the Spanish Ministry of Economy and Competitiveness"],"award-info":[{"award-number":["DPI2015-68820-R (MINECO\/FEDER), through the CERCA Programme, the Spanish Ministry of Economy and Competitiveness"]}],"id":[{"id":"10.13039\/501100002809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"he Biomedical Research Networking Centre in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN) (Instituto de Salud Carlos III\/FEDER)","award":["N\/A"],"award-info":[{"award-number":["N\/A"]}]},{"name":"European Respiratory Society Long-Term Research Fellowship","award":["ERS LTRF 2017 01-00086"],"award-info":[{"award-number":["ERS LTRF 2017 01-00086"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>To optimize long-term nocturnal non-invasive ventilation in patients with chronic obstructive pulmonary disease, surface diaphragm electromyography (EMGdi) might be helpful to detect patient-ventilator asynchrony. However, visual analysis is labor-intensive and EMGdi is heavily corrupted by electrocardiographic (ECG) activity. Therefore, we developed an automatic method to detect inspiratory onset from EMGdi envelope using fixed sample entropy (fSE) and a dynamic threshold based on kernel density estimation (KDE). Moreover, we combined fSE with adaptive filtering techniques to reduce ECG interference and improve onset detection. The performance of EMGdi envelopes extracted by applying fSE and fSE with adaptive filtering was compared to the root mean square (RMS)-based envelope provided by the EMG acquisition device. Automatic onset detection accuracy, using these three envelopes, was evaluated through the root mean square error (RMSE) between the automatic and mean visual onsets (made by two observers). The fSE-based method provided lower RMSE, which was reduced from 298 ms to 264 ms when combined with adaptive filtering, compared to 301 ms provided by the RMS-based method. The RMSE was negatively correlated with the proposed EMGdi quality indices. Following further validation, fSE with KDE, combined with adaptive filtering when dealing with low quality EMGdi, indicates promise for detecting the neural onset of respiratory drive.<\/jats:p>","DOI":"10.3390\/e21030258","type":"journal-article","created":{"date-parts":[[2019,3,8]],"date-time":"2019-03-08T04:58:35Z","timestamp":1552021115000},"page":"258","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Electromyography-Based Respiratory Onset Detection in COPD Patients on Non-Invasive Mechanical Ventilation"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0495-8422","authenticated-orcid":false,"given":"Leonardo","family":"Sarlabous","sequence":"first","affiliation":[{"name":"Biomedical Signal Processing and Interpretation, Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology (BIST), 08028 Barcelona, Spain"},{"name":"Department of Automatic Control (ESAII), Universitat Polit\u00e8cnica de Catalunya (UPC)\u2014Barcelona Tech, 08028 Barcelona, Spain"},{"name":"Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), 08028 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4126-4462","authenticated-orcid":false,"given":"Luis","family":"Estrada","sequence":"additional","affiliation":[{"name":"Biomedical Signal Processing and Interpretation, Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology (BIST), 08028 Barcelona, Spain"},{"name":"Department of Automatic Control (ESAII), Universitat Polit\u00e8cnica de Catalunya (UPC)\u2014Barcelona Tech, 08028 Barcelona, Spain"},{"name":"Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), 08028 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8257-8855","authenticated-orcid":false,"given":"Ana","family":"Cerezo-Hern\u00e1ndez","sequence":"additional","affiliation":[{"name":"Department of Pulmonology, Rio Hortega University Hospital, 47012 Valladolid, Spain"},{"name":"Department of Pulmonary Diseases\/Home mechanical Ventilation, University of Groningen, University Medical Center Groningen, 9713 Groningen, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sietske","family":"V. D. Leest","sequence":"additional","affiliation":[{"name":"Biomedical Signals and Systems Group, Faculty of Electrical Engineering, Mathematics &amp; Computer Science, University of Twente, 7500 Enschede, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Abel","family":"Torres","sequence":"additional","affiliation":[{"name":"Biomedical Signal Processing and Interpretation, Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology (BIST), 08028 Barcelona, Spain"},{"name":"Department of Automatic Control (ESAII), Universitat Polit\u00e8cnica de Catalunya (UPC)\u2014Barcelona Tech, 08028 Barcelona, Spain"},{"name":"Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), 08028 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6541-8729","authenticated-orcid":false,"given":"Raimon","family":"Jan\u00e9","sequence":"additional","affiliation":[{"name":"Biomedical Signal Processing and Interpretation, Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology (BIST), 08028 Barcelona, Spain"},{"name":"Department of Automatic Control (ESAII), Universitat Polit\u00e8cnica de Catalunya (UPC)\u2014Barcelona Tech, 08028 Barcelona, Spain"},{"name":"Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), 08028 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marieke","family":"Duiverman","sequence":"additional","affiliation":[{"name":"Department of Pulmonary Diseases\/Home mechanical Ventilation, University of Groningen, University Medical Center Groningen, 9713 Groningen, The Netherlands"},{"name":"Groningen Research Institute of Asthma and COPD (GRIAC), University of Groningen, 9712 Groningen, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9503-6908","authenticated-orcid":false,"given":"Ainara","family":"Garde","sequence":"additional","affiliation":[{"name":"Biomedical Signals and Systems Group, Faculty of Electrical Engineering, Mathematics &amp; Computer Science, University of Twente, 7500 Enschede, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,3,7]]},"reference":[{"key":"ref_1","unstructured":"GOLD: Global Initiative for Chronic Obstructive Lung Disease (2019, March 06). 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