{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,5]],"date-time":"2026-09-05T00:06:26Z","timestamp":1788566786346,"version":"build-2803163510"},"reference-count":34,"publisher":"MDPI AG","issue":"20","license":[{"start":{"date-parts":[[2023,10,19]],"date-time":"2023-10-19T00:00:00Z","timestamp":1697673600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>Free flap tissue transfer represents the gold standard for extensive defect reconstruction, although malperfusion due to thrombosis remains the leading risk factor for flap failure. Recent studies indicate an increased immune response and platelet activation in connection with pathologic coagulation. The underlying cellular and molecular mechanisms remain poorly understood, however. The presented study, therefore, aims to investigate if transfer-related ischemia alters intra-flap metabolism and electrolyte concentrations compared to central venous blood after free flap transfer in pigs to establish a novel experimental model. Free transfer of a myocutaneous gracilis flap to the axillary region was conducted in five juvenile male pigs. The flap artery was anastomosed to the axillary artery, and intra-flap venous blood was drained and transfused using a rubber-elastic fixed intravenous catheter. Blood gas analysis was performed to assess the effect of transfer time-induced ischemia on intra-flap electrolyte levels, acid\u2013base balance, and hemoglobin concentrations compared to central venous blood. Time to flap reperfusion was 52 \u00b1 10 min on average, resulting in a continuous pH drop (acidosis) in the flaps\u2019 venous blood compared to the central venous system (p = 0.037). Potassium (p = 0.016), sodium (p = 0.003), and chloride (p = 0.007) concentrations were significantly increased, whereas bicarbonate (p = 0.016) and calcium (p = 0.008) significantly decreased within the flap. These observations demonstrate the induction of anaerobic glycolysis and electrolyte displacement resulting in acidosis and hence significant tissue damage already after a short ischemic period, thereby validating the novel animal model for investigating intra-flap metabolism and offering opportunities for exploring various (immuno-) thrombo-hemostatic issues in transplantation surgery.<\/jats:p>","DOI":"10.3390\/jcm12206625","type":"journal-article","created":{"date-parts":[[2023,10,19]],"date-time":"2023-10-19T11:46:26Z","timestamp":1697715986000},"page":"6625","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["The Impact of Transfer-Related Ischemia on Free Flap Metabolism and Electrolyte Homeostasis\u2014A New In Vivo Experimental Approach in Pigs"],"prefix":"10.3390","volume":"12","author":[{"given":"Daniel","family":"Stephan","sequence":"first","affiliation":[{"name":"Department of Oral and Maxillofacial Surgery, Facial Plastic Surgery, University Medical Centre, Johannes Gutenberg University Mainz, Augustusplatz 2, 55131 Mainz, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sebastian","family":"Blatt","sequence":"additional","affiliation":[{"name":"Department of Oral and Maxillofacial Surgery, Facial Plastic Surgery, University Medical Centre, Johannes Gutenberg University Mainz, Augustusplatz 2, 55131 Mainz, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Julian","family":"Riedel","sequence":"additional","affiliation":[{"name":"Department of Anaesthesiology, University Medical Centre, Johannes Gutenberg University Mainz, Langenbeckstra\u00dfe 1, 55131 Mainz, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Katja","family":"Mohnke","sequence":"additional","affiliation":[{"name":"Department of Anaesthesiology, University Medical Centre, Johannes Gutenberg University Mainz, Langenbeckstra\u00dfe 1, 55131 Mainz, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Robert","family":"Ruemmler","sequence":"additional","affiliation":[{"name":"Department of Anaesthesiology, University Medical Centre, Johannes Gutenberg University Mainz, Langenbeckstra\u00dfe 1, 55131 Mainz, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexander","family":"Ziebart","sequence":"additional","affiliation":[{"name":"Department of Anaesthesiology, University Medical Centre, Johannes Gutenberg University Mainz, Langenbeckstra\u00dfe 1, 55131 Mainz, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bilal","family":"Al-Nawas","sequence":"additional","affiliation":[{"name":"Department of Oral and Maxillofacial Surgery, Facial Plastic Surgery, University Medical Centre, Johannes Gutenberg University Mainz, Augustusplatz 2, 55131 Mainz, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1671-3764","authenticated-orcid":false,"given":"Peer W.","family":"K\u00e4mmerer","sequence":"additional","affiliation":[{"name":"Department of Oral and Maxillofacial Surgery, Facial Plastic Surgery, University Medical Centre, Johannes Gutenberg University Mainz, Augustusplatz 2, 55131 Mainz, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4081-1487","authenticated-orcid":false,"given":"Daniel G. E.","family":"Thiem","sequence":"additional","affiliation":[{"name":"Department of Oral and Maxillofacial Surgery, Facial Plastic Surgery, University Medical Centre, Johannes Gutenberg University Mainz, Augustusplatz 2, 55131 Mainz, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,10,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1612","DOI":"10.1002\/lary.23775","article-title":"Outcomes in head and neck reconstruction by surgical site and donor site","volume":"123","author":"Frederick","year":"2013","journal-title":"Laryngoscope"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"167","DOI":"10.1016\/j.jcms.2012.07.005","article-title":"Free flaps in elderly patients: Outcomes and complications in head and neck reconstruction after oncological resection","volume":"41","author":"Ferrari","year":"2013","journal-title":"J. Craniomaxillofac. 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