Flap size as a confounding variable in flap perfusion measurement with the Oxygen-to-see (O2C) analysis system in microvascular head and neck reconstruction - a retrospective analysis.
Mark Ooms, Philipp Winnand, Marius Heitzer, Anna Bock, Marie Sophie Katz, Johannes Bickenbach, Frank Hölzle, Ali Modabber
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引用次数: 0
Abstract
Objectives: The Oxygen-to-see (O2C) analysis system is used for flap monitoring based on predefined threshold values for flap perfusion. However, flap size may be a confounding variable. The aim of this study was to investigate the relationship between flap size and flap perfusion in microvascular head and neck reconstruction.
Materials and methods: Flap perfusion values measured with the O2C analysis system between 2011 and 2020 in 252 patients undergoing microvascular head and neck reconstruction with a radial free forearm flap (RFFF) or anterolateral thigh flap (ALTF) were retrospectively analyzed. Intraoperative and postoperative flap blood flow, hemoglobin concentration, and hemoglobin oxygen saturation at 8- and 2-mm tissue depths were compared between small (≤ median flap size) and large flaps (> median flap size) for RFFFs and ALTFs separately.
Results: Intraoperative and postoperative hemoglobin concentration at a 2-mm tissue depth differed between small and large ALTFs (65.0 arbitrary units [AU] vs. 51.0 AU, p = 0.007; and 51.5 AU vs. 39.0 AU, p = 0.019). Both differences persisted in multivariable analysis (p < 0.001 and p = 0.012). Other differences were not observed or did not persist in multivariable analysis for RFFFs and ALTFs (all p > 0.05).
Conclusions: Microvascular free flap perfusion is not related to flap size in terms of flap blood flow and hemoglobin oxygen saturation. This underscores the validity of predefined absolute threshold values in the context of flap monitoring based on perfusion measurement with the O2C analysis system.
Clinical relevance: Flap perfusion measurement with the Oxygen-to-see (O2C) analysis system can be used for flap monitoring of small and large flaps.
期刊介绍：
The journal Clinical Oral Investigations is a multidisciplinary, international forum for publication of research from all fields of oral medicine. The journal publishes original scientific articles and invited reviews which provide up-to-date results of basic and clinical studies in oral and maxillofacial science and medicine. The aim is to clarify the relevance of new results to modern practice, for an international readership. Coverage includes maxillofacial and oral surgery, prosthetics and restorative dentistry, operative dentistry, endodontics, periodontology, orthodontics, dental materials science, clinical trials, epidemiology, pedodontics, oral implant, preventive dentistiry, oral pathology, oral basic sciences and more.
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