{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,14]],"date-time":"2026-09-14T22:34:49Z","timestamp":1789425289045,"version":"build-2803163510"},"reference-count":35,"publisher":"BMJ","issue":"5","license":[{"start":{"date-parts":[[2022,5,24]],"date-time":"2022-05-24T00:00:00Z","timestamp":1653350400000},"content-version":"unspecified","delay-in-days":23,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100010586","name":"Haukeland University Hospital","doi-asserted-by":"crossref","award":["Norwegian Advisory Unit on Home Mechanical Ventila"],"award-info":[{"award-number":["Norwegian Advisory Unit on Home Mechanical Ventila"]}],"id":[{"id":"10.13039\/501100010586","id-type":"DOI","asserted-by":"crossref"}]},{"name":"The Western Norway Regional Health Authority","award":["HelpILO"],"award-info":[{"award-number":["HelpILO"]}]}],"content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Open"],"accepted":{"date-parts":[[2022,5,8]]},"published-print":{"date-parts":[[2022,5]]},"abstract":"<jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>Application of non-invasive positive airway pressure may provoke laryngeal responses that obstruct the airways, especially in patients with disturbed laryngeal control. To control and adjust for this, transnasal fibre-optic laryngoscopy (TFL) is used to visualise laryngeal movements during therapeutic interventions. Being an invasive procedure, this may be unpleasant for patients. The aim of this study is to evaluate if ultrasound (US) imaging of the larynx may be used as an alternative less invasive diagnostic tool for evaluating the upper airway responses to non-invasive ventilation (NIV) and mechanical insufflation\u2013exsufflation (MI-E).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods and analysis<\/jats:title>\n                    <jats:p>This protocol presents an experimental cross-sectional study of a novel method to study laryngeal responses in adult healthy volunteers (n=30). The participants will be assessed with simultaneous TFL and laryngeal US imaging (anterior and lateral approaches) during NIV and MI-E therapy. Additionally, airflow and pressure signals will be registered during the procedures. The primary outcome is whether laryngeal US is a feasible method to study laryngeal responses and, if so, to compare the laryngeal responses visualised with TFL and US. The participants\u2019 perception of the examinations will be recorded. Secondary outcomes include airflow curve shapes and calculated ventilation volumes during the interventions.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Ethics and dissemination<\/jats:title>\n                    <jats:p>The study has been approved by The Regional Committee for Medical Research Ethics in Norway, and registered in ClinicalTrials.gov. Results will be disseminated through peer-reviewed journals, presentation of scientific abstracts at international medical conventions and oral presentations in relevant medical conventions.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Trial registration number<\/jats:title>\n                    <jats:p>\n                      <jats:ext-link xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" ext-link-type=\"clintrialgov\" xlink:href=\"NCT04586855\">NCT04586855<\/jats:ext-link>\n                      .\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.1136\/bmjopen-2021-059234","type":"journal-article","created":{"date-parts":[[2022,5,25]],"date-time":"2022-05-25T13:10:52Z","timestamp":1653484252000},"page":"e059234","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":13,"title":["Adjustments of non-invasive ventilation and mechanically assisted cough by combining ultrasound imaging of the larynx with transnasal fibre-optic laryngoscopy: a protocol for an experimental study"],"prefix":"10.1136","volume":"12","clinical-trial-number":[{"clinical-trial-number":"nct04586855","registry":"10.18810\/clinical-trials-gov"}],"author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3058-6156","authenticated-orcid":false,"given":"Anne Kristine","family":"Brekka","sequence":"first","affiliation":[{"name":"Department of Physiotherapy, Sorlandet Hospital HF, Arendal, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2545-0190","authenticated-orcid":false,"given":"Maria","family":"Volls\u00e6ter","sequence":"additional","affiliation":[{"name":"Norwegian Advisory Unit on Home Mechanical Ventilation, Haukeland University Hospital, Bergen, Norway"},{"name":"Faculty of Medicine, Department of Clinical Medicine, University of Bergen, Bergen, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1088-3009","authenticated-orcid":false,"given":"George","family":"Ntoumenopoulos","sequence":"additional","affiliation":[{"name":"Department of Physiotherapy, St Vincent\u2019s Hospital Sydney, Sydney, New South Wales, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0096-4032","authenticated-orcid":false,"given":"Hege Havstad","family":"Clemm","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, Department of Clinical Medicine, University of Bergen, Bergen, Norway"},{"name":"Department of Pediatrics, Haukeland University Hospital, Bergen, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1471-0225","authenticated-orcid":false,"given":"Thomas","family":"Halvorsen","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, Haukeland University Hospital, Bergen, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8381-0142","authenticated-orcid":false,"given":"Ola Drange","family":"R\u00f8ksund","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, Haukeland University Hospital, Bergen, Norway"},{"name":"The Faculty of Health and Social Sciences, Western Norway University of Applied Sciences, Bergen, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0641-3653","authenticated-orcid":false,"given":"Tiina Maarit","family":"Andersen","sequence":"additional","affiliation":[{"name":"Norwegian Advisory Unit on Home Mechanical Ventilation, Haukeland University Hospital, Bergen, Norway"},{"name":"The Faculty of Health and Social Sciences, Western Norway University of Applied Sciences, Bergen, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"239","published-online":{"date-parts":[[2022,5,25]]},"reference":[{"key":"2025121222203699000_12.5.e059234.1","doi-asserted-by":"crossref","unstructured":"Andersen TM , Hov B , Halvorsen T , et al . 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