Northwestern University Feinberg School of Medicine, Chicago, USA.
J Breast Cancer. 2013 Dec;16(4):426-31. doi: 10.4048/jbc.2013.16.4.426. Epub 2013 Dec 31.
Prosthetic-based breast reconstruction is performed with increasing frequency in the United States. Major mastectomy skin flap necrosis is a significant complication with outcomes ranging from poor aesthetic appearance to reconstructive failure. The present study aimed to explore the interactions between intraoperative fill and other risk factors on the incidence of flap necrosis in patients undergoing mastectomy with immediate expander/implant-based reconstruction.
A retrospective review of 966 consecutive patients (1,409 breasts) who underwent skin or nipple sparing mastectomy with immediate tissue expander reconstruction at a single institution was conducted. Age, body mass index, hypertension, smoking status, premastectomy and postmastectomy radiation, acellular dermal matrix use, and application of the tumescent mastectomy technique were analyzed as potential predictors of flap necrosis both independently and as synergistic variables with high intraoperative fill. The following three measures of interaction were calculated: relative excess risk due to interaction, attributable proportion of risk due to interaction, and synergy index (SI).
Intraoperative tissue expander fill volume was high (≥66.7% of the maximum volume) in 40.9% (576 of 1,409 breasts) of cases. The unadjusted flap necrosis rate was greater in the high intraoperative fill cohort than in the low fill cohort (10.4% vs. 7.1%, p=0.027). Multivariate logistic regression did not identify high intraoperative fill volume as an independent risk factor for flap necrosis (odds ratio 1.442, 95% confidence interval 0.973-2.137, p=0.068). However, four risk factors were identified that interacted significantly with intraoperative fill volume, namely tumescence, age, hypertension, and obesity. The SI, or the departure from additive risks, was largest for tumescence (SI, 25.3), followed by hypertension (SI, 2.39), obesity (SI, 2.28), and age older than 50 years (SI, 1.17).
In the postmastectomy, hypovascular milieu, multiple risk factors decreasing flap perfusion interact with high intraoperative fill volume to cross a threshold and synergistically increase the risk of flap necrosis.
在美国，假体辅助乳房重建的应用频率越来越高。乳房主要皮瓣坏死是一种严重的并发症，其结果从外观不佳到重建失败不等。本研究旨在探讨术中填充与其他危险因素之间的相互作用，以预测接受即刻扩张器/植入物乳房重建的乳房切除术患者皮瓣坏死的发生率。
对单中心 966 例（1409 侧）接受皮肤或乳头保留乳房切除术及即刻组织扩张器重建的患者进行回顾性分析。分析年龄、体重指数、高血压、吸烟状况、术前和术后放疗、脱细胞真皮基质的使用以及肿胀性乳房切除术技术的应用等因素，作为皮瓣坏死的潜在预测因子，这些因素既可以独立分析，也可以与术中高填充量作为协同变量进行分析。计算了以下三种交互作用的度量：交互作用引起的相对超额风险、交互作用引起的风险归因比例和协同指数（SI）。
术中组织扩张器填充量高（≥最大容量的 66.7%）的病例占 40.9%（576/1409 侧）。高术中填充组的皮瓣坏死率高于低填充组（10.4%比 7.1%，p=0.027）。多变量逻辑回归未发现术中高填充量是皮瓣坏死的独立危险因素（优势比 1.442，95%置信区间 0.973-2.137，p=0.068）。然而，有 4 个危险因素与术中填充量显著相互作用，即肿胀、年龄、高血压和肥胖。SI 值，即风险的非加性程度，肿胀最大（SI，25.3），其次是高血压（SI，2.39）、肥胖（SI，2.28）和年龄大于 50 岁（SI，1.17）。
在乳房切除术后的低血供环境中，降低皮瓣灌注的多个危险因素与高术中填充量相互作用，越过一个阈值，协同增加皮瓣坏死的风险。
