{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,12]],"date-time":"2026-06-12T06:00:35Z","timestamp":1781244035284,"version":"3.54.1"},"reference-count":48,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,6,12]],"date-time":"2026-06-12T00:00:00Z","timestamp":1781222400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Zhejiang Medical and Health Science and Technology Plan Project","award":["2020KY909"],"award-info":[{"award-number":["2020KY909"]}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["81800040"],"award-info":[{"award-number":["81800040"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Med."],"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Accurately predicting the risk of weaning failure is crucial for optimizing clinical decision-making and improving patient prognosis. Despite widespread use, the predictive value of diaphragm ultrasound remains controversial, and the compensatory role of auxiliary respiratory muscles has been overlooked. This study aims to evaluate whether the diaphragm-intercostal index (DII), a novel ultrasound index for joint assessment of diaphragm and intercostal muscle function, can predict weaning failure more accurately than traditional parameters.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>This prospective single-center cohort study enrolled invasive mechanical ventilation patients (\u226548\u202fh) ready for weaning. Ultrasound was performed 30\u202fmin into the spontaneous breathing trial (SBT) (pre-extubation, for primary predictive analysis) and 24\u202fh post-extubation (for exploratory descriptive analysis only). Measurements included diaphragmatic excursion (DE), diaphragm thickening fraction (TFdi), and intercostal muscle thickening fraction (TFic). DII was calculated as TFic\/TFdi. The primary outcome was weaning failure, defined as SBT failure or need for therapeutic non-invasive ventilation (NIV), reintubation, or death within 48\u202fh post-extubation. Sensitivity analysis was performed after excluding SBT failure patients to assess DII\u2019s performance in predicting true post-extubation failure. Lasso-logistic regression and ROC curves assessed predictive performance.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Of 107 patients, 81 weaned successfully and 26 failed. Among failures, 5 (19.23%) had SBT failure, 8 (30.77%) required reintubation, 11 (42.31%) required therapeutic NIV, and 2 (7.69%) died. DII\u2019s AUC was 0.952 (95% CI: 0.907\u20130.998), significantly outperforming RSBI (AUC\u202f=\u202f0.789) and TFdi (AUC\u202f=\u202f0.830). The optimal DII cutoff was &amp;gt;0.485 (sensitivity 80.8%, specificity 97.5%). In the sensitivity analysis excluding SBT failures, DII\u2019s AUC for predicting true post-extubation failure remained high at 0.942 (95% CI: 0.887\u20130.996), and DeLong test showed no significant difference from the primary analysis (\n                      <jats:italic>p<\/jats:italic>\n                      =\u202f0.779).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>DII can effectively quantify the compensation of the auxiliary respiratory muscles relative to the diaphragm, showing favorable predictive performance for predicting weaning failure, strikingly superior to traditional parameters. However, validation in large-scale, multi-center studies is needed, particularly after standardizing SBT protocols with positive end-expiratory pressure (PEEP) as per guidelines, and in populations including obese and heart failure patients.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fmed.2026.1823331","type":"journal-article","created":{"date-parts":[[2026,6,12]],"date-time":"2026-06-12T05:48:06Z","timestamp":1781243286000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["The diaphragm-intercostal index for predicting weaning failure in mechanically ventilated patients: a prospective cohort study"],"prefix":"10.3389","volume":"13","author":[{"given":"Lei","family":"Zhang","sequence":"first","affiliation":[{"name":"Department of Respiratory and Critical Care Medicine, The Affiliated People\u2019s Hospital of Ningbo University","place":["Ningbo, Zhejiang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhijia","family":"Zhao","sequence":"additional","affiliation":[{"name":"Medical Record Statistics Room, The Affiliated People\u2019s Hospital of Ningbo University, Ningbo","place":["Zhejiang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yaling","family":"Wu","sequence":"additional","affiliation":[{"name":"Child Rehabilitation Division, Ningbo Rehabilitation Hospital","place":["Ningbo, Zhejiang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ning","family":"Zhu","sequence":"additional","affiliation":[{"name":"Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital of Ningbo University","place":["Ningbo, Zhejiang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shiyi","family":"Liu","sequence":"additional","affiliation":[{"name":"Department of Critical Care Medicine, The Affiliated People\u2019s Hospital of Ningbo University","place":["Ningbo, Zhejiang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jingjing","family":"Zhou","sequence":"additional","affiliation":[{"name":"Ningbo Municipal Hospital of Traditional Chinese Medicine (TCM), Affiliated Hospital of Zhejiang Chinese Medical University","place":["Ningbo, Zhejiang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Guozhong","family":"Chen","sequence":"additional","affiliation":[{"name":"Department of Critical Care Medicine, The Affiliated People\u2019s Hospital of Ningbo University","place":["Ningbo, Zhejiang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wanjun","family":"Yu","sequence":"additional","affiliation":[{"name":"Department of Respiratory and Critical Care Medicine, The Affiliated People\u2019s Hospital of Ningbo University","place":["Ningbo, Zhejiang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,6,12]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"103302","DOI":"10.1016\/j.iccn.2022.103302","article-title":"Informing the standardising of care for prolonged stay patients in the intensive care unit: a scoping review of quality improvement tools","volume":"73","author":"Allum","year":"2022","journal-title":"Intensive Crit Care Nurs"},{"key":"ref2","doi-asserted-by":"publisher","first-page":"829","DOI":"10.4187\/respcare.11077","article-title":"Effect of reintubation within 48 hours on mortality in critically ill patients after planned Extubation","volume":"69","author":"Dadam","year":"2024","journal-title":"Respir Care"},{"key":"ref3","doi-asserted-by":"publisher","first-page":"801","DOI":"10.1007\/s00134-013-2823-1","article-title":"Sonographic evaluation of the diaphragm in critically ill patients. 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