{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,21]],"date-time":"2026-05-21T12:21:03Z","timestamp":1779366063856,"version":"3.53.0"},"reference-count":42,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2021,6,22]],"date-time":"2021-06-22T00:00:00Z","timestamp":1624320000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003196","name":"Ministero della Salute","doi-asserted-by":"publisher","award":["GR-2013-02356711"],"award-info":[{"award-number":["GR-2013-02356711"]}],"id":[{"id":"10.13039\/501100003196","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Membranes"],"abstract":"<jats:p>Extracorporeal carbon dioxide removal (ECCO2R) is a promising strategy to manage acute respiratory failure. We hypothesized that ECCO2R could be enhanced by ventilating the membrane lung with a sodium hydroxide (NaOH) solution with high CO2 absorbing capacity. A computed mathematical model was implemented to assess NaOH\u2013CO2 interactions. Subsequently, we compared NaOH infusion, named \u201calkaline liquid ventilation\u201d, to conventional oxygen sweeping flows. We built an extracorporeal circuit with two polypropylene membrane lungs, one to remove CO2 and the other to maintain a constant PCO2 (60 \u00b1 2 mmHg). The circuit was primed with swine blood. Blood flow was 500 mL \u00d7 min\u22121. After testing the safety and feasibility of increasing concentrations of aqueous NaOH (up to 100 mmol \u00d7 L\u22121), the CO2 removal capacity of sweeping oxygen was compared to that of 100 mmol \u00d7 L\u22121 NaOH. We performed six experiments to randomly test four sweep flows (100, 250, 500, 1000 mL \u00d7 min\u22121) for each fluid plus 10 L \u00d7 min\u22121 oxygen. Alkaline liquid ventilation proved to be feasible and safe. No damages or hemolysis were detected. NaOH showed higher CO2 removal capacity compared to oxygen for flows up to 1 L \u00d7 min\u22121. However, the highest CO2 extraction power exerted by NaOH was comparable to that of 10 L \u00d7 min\u22121 oxygen. Further studies with dedicated devices are required to exploit potential clinical applications of alkaline liquid ventilation.<\/jats:p>","DOI":"10.3390\/membranes11070464","type":"journal-article","created":{"date-parts":[[2021,6,22]],"date-time":"2021-06-22T22:10:59Z","timestamp":1624399859000},"page":"464","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Alkaline Liquid Ventilation of the Membrane Lung for Extracorporeal Carbon Dioxide Removal (ECCO2R): In Vitro Study"],"prefix":"10.3390","volume":"11","author":[{"given":"Luigi","family":"Vivona","sequence":"first","affiliation":[{"name":"Anesthesia and Critical Care, Department of Pathophysiology and Transplantation, University of Milan, 20122 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5502-7601","authenticated-orcid":false,"given":"Michele","family":"Battistin","sequence":"additional","affiliation":[{"name":"Center for Preclinical Research, Fondazione IRCCS Ca\u2019 Granda-Ospedale Maggiore Policlinico, 20122 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eleonora","family":"Carlesso","sequence":"additional","affiliation":[{"name":"Anesthesia and Critical Care, Department of Pathophysiology and Transplantation, University of Milan, 20122 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9725-8520","authenticated-orcid":false,"given":"Thomas","family":"Langer","sequence":"additional","affiliation":[{"name":"Department of Anesthesia and Intensive Care Medicine, Niguarda Ca\u2019 Granda, 20162 Milan, Italy"},{"name":"Department of Medicine and Surgery, University of Milan-Bicocca, 20900 Monza, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Carlo","family":"Valsecchi","sequence":"additional","affiliation":[{"name":"Dipartimento di Anestesia, Rianimazione ed Emergenza Urgenza, Fondazione IRCCS Ca\u2019 Granda-Ospedale Maggiore Policlinico, 20122 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9612-5187","authenticated-orcid":false,"given":"Sebastiano Maria","family":"Colombo","sequence":"additional","affiliation":[{"name":"Anesthesia and Critical Care, Department of Pathophysiology and Transplantation, University of Milan, 20122 Milan, Italy"},{"name":"Dipartimento di Anestesia, Rianimazione ed Emergenza Urgenza, Fondazione IRCCS Ca\u2019 Granda-Ospedale Maggiore Policlinico, 20122 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Serena","family":"Todaro","sequence":"additional","affiliation":[{"name":"Anesthesia and Critical Care, Department of Pathophysiology and Transplantation, University of Milan, 20122 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stefano","family":"Gatti","sequence":"additional","affiliation":[{"name":"Center for Preclinical Research, Fondazione IRCCS Ca\u2019 Granda-Ospedale Maggiore Policlinico, 20122 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gaetano","family":"Florio","sequence":"additional","affiliation":[{"name":"Anesthesia and Critical Care, Department of Pathophysiology and Transplantation, University of Milan, 20122 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Antonio","family":"Pesenti","sequence":"additional","affiliation":[{"name":"Anesthesia and Critical Care, Department of Pathophysiology and Transplantation, University of Milan, 20122 Milan, Italy"},{"name":"Dipartimento di Anestesia, Rianimazione ed Emergenza Urgenza, Fondazione IRCCS Ca\u2019 Granda-Ospedale Maggiore Policlinico, 20122 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giacomo","family":"Grasselli","sequence":"additional","affiliation":[{"name":"Anesthesia and Critical Care, Department of Pathophysiology and Transplantation, University of Milan, 20122 Milan, Italy"},{"name":"Dipartimento di Anestesia, Rianimazione ed Emergenza Urgenza, Fondazione IRCCS Ca\u2019 Granda-Ospedale Maggiore Policlinico, 20122 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2967-2527","authenticated-orcid":false,"given":"Alberto","family":"Zanella","sequence":"additional","affiliation":[{"name":"Anesthesia and Critical Care, Department of Pathophysiology and Transplantation, University of Milan, 20122 Milan, Italy"},{"name":"Dipartimento di Anestesia, Rianimazione ed Emergenza Urgenza, Fondazione IRCCS Ca\u2019 Granda-Ospedale Maggiore Policlinico, 20122 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,6,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"138","DOI":"10.1097\/00000542-197702000-00012","article-title":"Control of breathing using an extracorporeal membrane lung","volume":"46","author":"Kolobow","year":"1977","journal-title":"Anesthesiology"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"826","DOI":"10.1097\/ALN.0b013e3181b764d2","article-title":"Tidal volume lower than 6 ml\/kg enhances lung protection: Role of extracorporeal carbon dioxide removal","volume":"111","author":"Terragni","year":"2009","journal-title":"Anesthesiology"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"592","DOI":"10.1007\/s00134-019-05567-4","article-title":"European Society of Intensive Care Medicine Trials Group; the \u201cStrategy of Ultra-Protective lung ventilation with Extracorporeal CO2 Removal for New-Onset moderate to severe ARDS\u201d (SUPERNOVA) investigators. 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