{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,3]],"date-time":"2026-08-03T11:45:05Z","timestamp":1785757505592,"version":"3.56.0"},"reference-count":35,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,8,1]],"date-time":"2026-08-01T00:00:00Z","timestamp":1785542400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Med. Sci.","Medical Sciences"],"abstract":"<jats:p>Background\/Objectives: Positive end-expiratory pressure (PEEP) increases end-expiratory lung volume through the addition of PEEP-induced lung volume (PEEPVol), potentially affecting respiratory mechanics and energy load. However, its physiological impact in patients without lung injury remains poorly characterized. We hypothesized that PEEPVol would be closely associated with respiratory system loading beyond conventional respiratory mechanics variables. Methods: We conducted a secondary analysis of a prospective physiological study including 16 deeply sedated, mechanically ventilated adults without lung disease. A standardized incremental PEEP titration (0\u201316 cmH2O, steps of 4 cmH2O) was performed under volume-controlled ventilation. At each step, respiratory mechanics were assessed, including static compliance (Cstat), driving pressure, plateau pressure, and mechanical power. PEEPVol was estimated as PEEP \u00d7 Cstat, and strain indices were derived relative to predicted functional residual capacity. Linear mixed-effects models evaluated changes across PEEP levels, and associations were initially explored using Spearman correlation and linear regression. To account for repeated measurements within subjects, confirmatory linear mixed-effects regression models were subsequently performed using patients as a random intercept. Results: Incremental PEEP significantly increased PEEPVol, plateau pressure, mechanical power, and both static and global strain (all p &lt; 0.001), while changes in compliance and driving pressure were minimal and not clinically meaningful. PEEPVol showed moderate-to-strong correlations with plateau pressure (\u03c1 = 0.68) and mechanical power (\u03c1 = 0.76) and explained 43% and 56% of their variance, respectively (all p &lt; 0.001);these associations remained significant in additional linear mixed-effects regression analyses accounting for within-subject correlation. PEEPVol also correlated strongly with static strain (\u03c1 = 0.93) and global strain (\u03c1 = 0.83); however, because static strain is calculated as PEEPVol\/FRCt, this association is mathematically expected rather than an independent physiological finding and is reported here only for completeness. Notably, 11.1% of measurements exceeded Pplat &gt; 30 cmH2O and 61.9% exceeded MP \u2265 17 J\/min, even at moderate PEEP levels. Conclusions: In patients without lung injury, PEEP-induced increases in lung volume are strongly associated with higher mechanical load and strain, despite minimal changes in compliance or driving pressure. PEEPVol may represent a promising physiological surrogate of static lung deformation and energy transfer, whose potential to improve bedside detection of occult overdistension warrants validation against direct imaging or physiological measurements in larger prospective studies.<\/jats:p>","DOI":"10.3390\/medsci14040451","type":"journal-article","created":{"date-parts":[[2026,8,3]],"date-time":"2026-08-03T10:24:07Z","timestamp":1785752647000},"page":"451","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Bedside Assessment of PEEP-Induced Volume and Mechanical Power in Mechanically Ventilated Adults Without ARDS: A Post Hoc Analysis"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9729-4839","authenticated-orcid":false,"given":"Adri\u00e1n","family":"Gallardo","sequence":"first","affiliation":[{"name":"Servicio de Kinesiolog\u00eda y Cuidados Respiratorios, Sanatorio Cl\u00ednica Modelo de Mor\u00f3n, Mor\u00f3n C1015, Argentina"},{"name":"Departamento de Ciencias de la Salud, Kinesiolog\u00eda y Fisiatr\u00eda, Universidad Nacional de la Matanza, San Justo B1754, Argentina"},{"name":"WeVent, Grupo Internacional de Ventilaci\u00f3n Mec\u00e1nica, Vi\u00f1a del Mar 2520000, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9858-6035","authenticated-orcid":false,"given":"Armando","family":"D\u00edaz-Cabrera","sequence":"additional","affiliation":[{"name":"Hospital San Juan de Dios, Santiago 8350488, Chile"},{"name":"Exercise and Rehabilitation Sciences Institute, School of Physical Therapy, Faculty of Rehabilitation Sciences, Universidad Andres Bello, Santiago 7591538, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cristian","family":"Deana","sequence":"additional","affiliation":[{"name":"Anesthesia and Intensive Care 1, Department of Anesthesia and Intensive Care, Health Integrated Agency of Friuli Centrale, 33100 Udine, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3745-8368","authenticated-orcid":false,"given":"Luigi","family":"Vetrugno","sequence":"additional","affiliation":[{"name":"Anesthesia and Intensive Care Unit, Department of Emergency, Health Integrated Agency of Friuli Centrale, Tolmezzo Hospital, 33028 Tolmezzo, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3490-553X","authenticated-orcid":false,"given":"Mauro","family":"Castro-Sayat","sequence":"additional","affiliation":[{"name":"Departamento de Emergencias, Unidad de Soporte Respiratorio No Invasivo, Hospital Juan A Fern\u00e1ndez, Buenos Aires C1425, Argentina"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Acute Respiratory Distress Syndrome Network, Brower, R.G., Matthay, M.A., Morris, A., Schoenfeld, D., Thompson, B.T., and Wheeler, A. 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