• Jakob Wittenstein, Robert Huhle, Martin Scharffenberg, Thomas Kiss, Johannes Herold, Luigi Vivona, Alice Bergamaschi, Marcus J Schultz, Paolo Pelosi, Gama de Abreu Marcelo M, and Thomas Bluth.
• From the Department of Anaesthesiology and Intensive Care Medicine, Pulmonary Engineering Group, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany (JW, RH, MS, TK, JH, LV, AB, MGdeA, TB), Department of Pathophysiology and Transplantation, University of Milan, Milan (LV), San Martino Hospital, IRCCS for Oncology, Department of Surgical Sciences and Integrated Diagnostics, University of Genoa, Genoa, Italy (AB, PP), Department of Intensive Care and Laboratory of Experimental Intensive Care and Anaesthesiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands (MJS), Department of Surgical Sciences and Integrated Diagnostics, University of Genoa, Genoa, Italy (PP) and Outcomes Research Consortium, Cleveland, Ohio, USA (MGdeA).
• Eur J Anaesthesiol. 2021 Jun 1; 38 (6): 634-643.

BackgroundLung recruitment manoeuvres and positive end-expiratory pressure (PEEP) can improve lung function during general anaesthesia. Different recruitment manoeuvre strategies have been described in large international trials: in the protective ventilation using high vs. low PEEP (PROVHILO) strategy, tidal volume (VT) was increased during volume-controlled ventilation; in the individualised peri-operative open-lung approach vs. standard protective ventilation in abdominal surgery (iPROVE) strategy, PEEP was increased during pressure-controlled ventilation.ObjectivesTo compare the effects of the PROVHILO strategy and the iPROVE strategy on respiratory and haemodynamic variables.DesignRandomised crossover study.SettingUniversity hospital research facility.AnimalsA total of 20 juvenile anaesthetised pigs.InterventionsAnimals were assigned randomly to one of two sequences: PROVHILO strategy followed by iPROVE strategy or vice-versa (n = 10/sequence). In the PROVHILO strategy, VT was increased stepwise by 4 ml kg-1 at a fixed PEEP of 12 cmH2O until a plateau pressure of 30 to 35 cmH2O was reached. In the iPROVE strategy, at fixed driving pressure of 20 cmH2O, PEEP was increased up to 20 cmH2O followed by PEEP titration according to the lowest elastance of the respiratory system (ERS).Main Outcome MeasuresWe assessed regional transpulmonary pressure (Ptrans), respiratory system mechanics, gas exchange and haemodynamics, as well as the centre of ventilation (CoV) by electrical impedance tomography.ResultsDuring recruitment manoeuvres with the PROVHILO strategy compared with the iPROV strategy, dorsal Ptrans was lower at end-inspiration (16.3 ± 2.7 vs. 18.6 ± 3.1 cmH2O, P = 0.001) and end-expiration (4.8 ± 2.6 vs. 8.8 ± 3.4 cmH2O, P  < 0.001), and mean arterial pressure (MAP) was higher (77 ± 11 vs. 60 ± 14 mmHg, P < 0.001). At 1 and 15 min after recruitment manoeuvres, ERS was higher in the PROVHILO strategy than the iPROVE strategy (24.6 ± 3.9 vs. 21.5 ± 3.4 and 26.7 ± 4.3 vs. 24.0 ± 3.8 cmH2O l-1; P  < 0.001, respectively). At 1 min, PaO2 was lower in PROVHILO compared with iPROVE strategy (57.1 ± 6.1 vs. 59.3 ± 5.1 kPa, P = 0.013), but at 15 min, values did not differ. CoV did not differ between strategies.ConclusionIn anaesthetised pigs, the iPROVE strategy compared with the PROVHILO strategy increased dorsal Ptrans at the cost of lower MAP during recruitment manoeuvres, and decreased ERS thereafter, without consistent improvement of oxygenation or shift of the CoV.Trial RegistrationThis study was registered and approved by the Landesdirektion Dresden, Germany (DD24-5131/338/28).Copyright © 2021 European Society of Anaesthesiology and Intensive Care. Unauthorized reproduction of this article is prohibited.

8 keywords...

hide…