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Individualized positive end-expiratory pressure (iPEEP) along with other lung-protective strategies is effective in alleviating postoperative atelectasis. Here, we compared the best static lung compliance (Cstat) titration of iPEEP with electrical impedance tomography (EIT) titration to observe their effects on postoperative atelectasis in obese patients undergoing laparoscopic surgery.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Methods<\/jats:title>\n                <jats:p>A total number of 140 obese patients with BMI \u2265 32.5kg\/m<jats:sup>2<\/jats:sup> undergoing elective laparoscopic gastric volume reduction and at moderate to high risk of developing PPCs will be enrolled and randomized into the optimal static lung compliance-directed iPEEP group and EIT titration iPEEP group. The primary endpoint will be pulmonary atelectasis measured and calculated by EIT immediately after extubation and 2 h after surgery. Secondary endpoints will be intraoperative oxygenation index, organ dysfunction, incidence of PPCs, hospital expenses, and length of hospital stay.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Discussion<\/jats:title>\n                <jats:p>Many iPEEP titration methods effective for normal weight patients may not be appropriate for obese patients. Although EIT-guided iPEEP titration is effective in obese patients, its high price and complexity limit its application in many clinical facilities. This trial will test the efficacy of iPEEP via the optimal static lung compliance-guided titration procedure by comparing it with EIT-guided PEEP titration. The results of this trial will provide a feasible and convenient method for anesthesiologists to set individualized PEEP for obese patients during laparoscopic surgery.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Trial registration<\/jats:title>\n                <jats:p><jats:ext-link xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" ext-link-type=\"uri\" xlink:href=\"http:\/\/clinicaltrials.gov\">ClinicalTrials.gov<\/jats:ext-link><jats:ext-link xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" ext-link-type=\"uri\" xlink:href=\"https:\/\/www.chictr.org.cn\/showproj.aspx?proj=62257\">ChiCTR2000039144<\/jats:ext-link>. Registered on October 19, 2020<\/jats:p>\n              <\/jats:sec>","DOI":"10.1186\/s13063-021-05671-1","type":"journal-article","created":{"date-parts":[[2021,10,15]],"date-time":"2021-10-15T20:20:01Z","timestamp":1634329201000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Effects of individualized PEEP obtained by two different titration methods on postoperative atelectasis in obese patients: study protocol for a randomized controlled trial"],"prefix":"10.1186","volume":"22","author":[{"given":"Qing-Yuan","family":"Wang","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yu-Wei","family":"Ji","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6344-4010","authenticated-orcid":false,"given":"Li-Xin","family":"An","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lei","family":"Cao","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fu-Shan","family":"Xue","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2021,10,15]]},"reference":[{"issue":"23","key":"5671_CR1","doi-asserted-by":"publisher","first-page":"2292","DOI":"10.1001\/jama.2019.7505","volume":"321","author":"T Bluth","year":"2019","unstructured":"Writing Committee for the PROBESE Collaborative Group of the PROtective VEntilation Network (PROVEnet) for the Clinical Trial Network of the European Society of Anaesthesiology, Bluth T, Serpa Neto A, Schultz MJ, Pelosi P, Gama de Abreu M, et al. 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All enrolled patients fulfilling the inclusion criteria are required to provide written informed consent the day prior to surgery. Subjects have the right to withdraw their consent any time during the trial.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethics approval and consent to participate"}},{"value":"Not applicable.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Consent for publication"}},{"value":"The authors declare that they have no competing interests.","order":4,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing interests"}}],"article-number":"704"}}