{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,12]],"date-time":"2026-01-12T05:35:07Z","timestamp":1768196107688,"version":"3.49.0"},"reference-count":46,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2023,6,8]],"date-time":"2023-06-08T00:00:00Z","timestamp":1686182400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>Background: Changing trunk inclination affects lung function in patients with ARDS. However, its impacts on PEEP titration remain unknown. The primary aim of this study was to assess, in mechanically ventilated patients with COVID-19 ARDS, the effects of trunk inclination on PEEP titration. The secondary aim was to compare respiratory mechanics and gas exchange in the semi-recumbent (40\u00b0 head-of-the-bed) and supine-flat (0\u00b0) positions following PEEP titration. Methods: Twelve patients were positioned both at 40\u00b0 and 0\u00b0 trunk inclination (randomized order). The PEEP associated with the best compromise between overdistension and collapse guided by Electrical Impedance Tomography (PEEPEIT) was set. After 30 min of controlled mechanical ventilation, data regarding respiratory mechanics, gas exchange, and EIT parameters were collected. The same procedure was repeated for the other trunk inclination. Results: PEEPEIT was lower in the semi-recumbent than in the supine-flat position (8 \u00b1 2 vs. 13 \u00b1 2 cmH2O, p &lt; 0.001). A semi-recumbent position with optimized PEEP resulted in higher PaO2:FiO2 (141 \u00b1 46 vs. 196 \u00b1 99, p = 0.02) and a lower global inhomogeneity index (46 \u00b1 10 vs. 53 \u00b1 11, p = 0.008). After 30 min of observation, a loss of aeration (measured by EIT) was observed only in the supine-flat position (\u2212153 \u00b1 162 vs. 27 \u00b1 203 mL, p = 0.007). Conclusions: A semi-recumbent position is associated with lower PEEPEIT and results in better oxygenation, less derecruitment, and more homogenous ventilation compared to the supine-flat position.<\/jats:p>","DOI":"10.3390\/jcm12123914","type":"journal-article","created":{"date-parts":[[2023,6,8]],"date-time":"2023-06-08T02:02:28Z","timestamp":1686189748000},"page":"3914","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["PEEP Titration Is Markedly Affected by Trunk Inclination in Mechanically Ventilated Patients with COVID-19 ARDS: A Physiologic, Cross-Over Study"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5407-6615","authenticated-orcid":false,"given":"Francesco","family":"Marrazzo","sequence":"first","affiliation":[{"name":"Department of Anesthesia and Critical Care, ASST Grande Ospedale Metropolitano Niguarda, 20162 Milano, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3210-1714","authenticated-orcid":false,"given":"Stefano","family":"Spina","sequence":"additional","affiliation":[{"name":"Department of Anesthesia and Critical Care, ASST Grande Ospedale Metropolitano Niguarda, 20162 Milano, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2377-3992","authenticated-orcid":false,"given":"Francesco","family":"Zadek","sequence":"additional","affiliation":[{"name":"School of Medicine and Surgery, University of Milano-Bicocca, 20126 Milano, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1858-1080","authenticated-orcid":false,"given":"Clarissa","family":"Forlini","sequence":"additional","affiliation":[{"name":"Department of Anesthesia and Critical Care, ASST Grande Ospedale Metropolitano Niguarda, 20162 Milano, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gabriele","family":"Bassi","sequence":"additional","affiliation":[{"name":"Department of Anesthesia and Critical Care, ASST Grande Ospedale Metropolitano Niguarda, 20162 Milano, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2202-6194","authenticated-orcid":false,"given":"Riccardo","family":"Giudici","sequence":"additional","affiliation":[{"name":"Department of Anesthesia and Critical Care, ASST Grande Ospedale Metropolitano Niguarda, 20162 Milano, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3089-205X","authenticated-orcid":false,"given":"Giacomo","family":"Bellani","sequence":"additional","affiliation":[{"name":"School of Medicine and Surgery, University of Milano-Bicocca, 20126 Milano, Italy"},{"name":"Department of Anesthesia and Intensive Care 1, Santa Chiara Hospital, APSS Trento, 38122 Trento, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0398-1329","authenticated-orcid":false,"given":"Roberto","family":"Fumagalli","sequence":"additional","affiliation":[{"name":"Department of Anesthesia and Critical Care, ASST Grande Ospedale Metropolitano Niguarda, 20162 Milano, Italy"},{"name":"School of Medicine and Surgery, University of Milano-Bicocca, 20126 Milano, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9725-8520","authenticated-orcid":false,"given":"Thomas","family":"Langer","sequence":"additional","affiliation":[{"name":"Department of Anesthesia and Critical Care, ASST Grande Ospedale Metropolitano Niguarda, 20162 Milano, Italy"},{"name":"School of Medicine and Surgery, University of Milano-Bicocca, 20126 Milano, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,6,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2126","DOI":"10.1056\/NEJMra1208707","article-title":"Ventilator-Induced Lung Injury","volume":"369","author":"Slutsky","year":"2013","journal-title":"N. 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