Weinzierl Andrea, Harder Yves, Menger Michael D, Laschke Matthias W
From the Institute for Clinical and Experimental Surgery, Saarland University.
Department of Plastic, Reconstructive, and Aesthetic Surgery, Ospedale Regionale di Lugano, Ente Ospedaliero Cantonale.
Plast Reconstr Surg. 2023 May 1;151(5):1030-1041. doi: 10.1097/PRS.0000000000010085. Epub 2022 Dec 20.
Dietary restriction, such as intermittent fasting (IF), has previously been shown to protect various tissues from ischemia-induced necrosis. Based on this finding, the authors herein evaluated for the first time the tissue-protective effects of IF in musculocutaneous flaps.
Male C57BL/6N mice were randomly assigned to an IF group ( n = 8) and a control group with unrestricted access to standard diet ( n = 8). IF animals were put on a perioperative feeding schedule with 8 hours of unrestricted access to standard diet per day starting 7 days before flap elevation up to 3 days after surgery. Random pattern musculocutaneous flaps were raised and mounted into a dorsal skinfold chamber. Intravital fluorescence microscopy was performed on days 1, 3, 5, 7, and 10 after surgery for the quantitative assessment of angiogenesis, nutritive blood perfusion, and flap necrosis. After the in vivo observation period, the flaps were harvested for additional histologic and immunohistochemical analyses.
The authors found that the IF group exhibited more newly formed microvessels and a higher functional capillary density within the flap tissue when compared with controls. This was associated with a significantly lower rate of tissue necrosis. Immunohistochemical detection of different inflammatory cell subtypes revealed a markedly reduced number of invading myeloperoxidase-positive neutrophilic granulocytes in the musculocutaneous tissue of IF-treated animals.
Considered together, these findings indicate that IF prevents flap necrosis by maintaining nutritive tissue perfusion and suppressing ischemia-induced inflammation.
Given the frequent use of flaps in plastic surgery and the high rates of ischemic complications, any new approach to decrease such complications is clinically relevant.
此前已证明，饮食限制，如间歇性禁食（IF），可保护各种组织免受缺血性坏死。基于这一发现，作者在此首次评估了IF对肌皮瓣的组织保护作用。
将雄性C57BL/6N小鼠随机分为IF组（n = 8）和对照组（n = 8），对照组可自由摄取标准饮食。IF组动物从皮瓣掀起前7天至术后3天，采用围手术期喂养方案，每天有8小时可自由摄取标准饮食。掀起随机型肌皮瓣并将其植入背部皮褶腔。在术后第1、3、5、7和10天进行活体荧光显微镜检查，以定量评估血管生成、营养性血液灌注和皮瓣坏死情况。在体内观察期结束后，切取皮瓣进行额外的组织学和免疫组织化学分析。
作者发现，与对照组相比，IF组皮瓣组织内新形成的微血管更多，功能性毛细血管密度更高。这与组织坏死率显著降低有关。对不同炎症细胞亚型的免疫组织化学检测显示，IF处理动物的肌皮组织中，侵入的髓过氧化物酶阳性中性粒细胞数量明显减少。
综合来看，这些发现表明IF通过维持营养性组织灌注和抑制缺血性炎症来预防皮瓣坏死。
鉴于皮瓣在整形外科中的频繁使用以及缺血性并发症的高发生率，任何降低此类并发症的新方法都具有临床相关性。
