Benites, Martín HernánZapata‑Canivilo, MarceloPoblete, FabianLabbe, FranciscoBattiato, RominaFerre, AndrésDreyse, JorgeBugedo, GuillermoBruhn, AlejandroCosta, Eduardo L. V.Retamal, Jaime2024-11-272024-11-272024-07-09Critical Care, Vol. 28, N°228 (2024) p. 1-161364-8535http://hdl.handle.net/20.500.12254/3928Background Adjusting trunk inclination from a semirecumbent position to a supinefat position or vice versa in patients with respiratory failure signifcantly afects numerous aspects of respiratory physiology including respiratory mechanics, oxygenation, endexpiratory lung volume, and ventilatory efciency. Despite these observed efects, the current clinical evidence regarding this positioning manoeuvre is limited. This study undertakes a scoping review of patients with respiratory failure undergoing mechanical ventilation to assess the efect of trunk inclination on physiological lung parameters. Methods The PubMed, Cochrane, and Scopus databases were systematically searched from 2003 to 2023. Interventions: Changes in trunk inclination. Measurements: Four domains were evaluated in this study: 1) respiratory mechanics, 2) ventilation distribution, 3) oxygenation, and 4) ventilatory efciency. Results After searching the three databases and removing duplicates, 220 studies were screened. Of these, 37 were assessed in detail, and 13 were included in the fnal analysis, comprising 274 patients. All selected studies were experimental, and assessed respiratory mechanics, ventilation distribution, oxygenation, and ventilatory efciency, primarily within 60 min post postural change. Conclusion In patients with acute respiratory failure, transitioning from a supine to a semirecumbent position leads to decreased respiratory system compliance and increased airway driving pressure. Additionally, CARDS patients experienced an improvement in ventilatory efciency, which resulted in lower PaCO2 levels. Improvements in oxygenation were observed in a few patients and only in those who exhibited an increase in EELV upon moving to a semi recumbent position. Therefore, the trunk inclination angle must be accurately reported in patients with respiratory failure under mechanical ventilationenAtribución-NoComercial-CompartirIgual 3.0 Chile (CC BY-NC-SA 3.0 CL)Acute respiratory distress syndromeBody positionEndexpiratory lung volumeRespiratory dead spaceTrunk inclinationArticlehttps://orcid.org/0000-0001-6366-534Xhttps://orcid.org/0000-0003-1770-244Xhttps://orcid.org/0000-0002-8201-5956https://doi.org/10.1186/s13054-024-05010-1