Data_Sheet_1_The impact of preoperative nutritional screening, ERAS protocol, and mini-invasive surgery in surgical oncology: A multi-institutional SEM analysis of patients with digestive cancer.docx

BackgroundMini-invasive surgery (MIS), ERAS, and preoperative nutritional screening are currently used to reduce complications and the length of hospital stay (LOS); however, inter-variable correlations have seldom been explored. This research aimed to define inter-variable correlations in a large series of patients with gastrointestinal cancer and their impact on outcomes.
MethodsPatients with consecutive cancer who underwent radical gastrointestinal surgery between 2019 and 2020 were analyzed. Age, BMI, comorbidities, ERAS, nutritional screening, and MIS were evaluated to determine their impact on 30-day complications and LOS. Inter-variable correlations were measured, and a latent variable was computed to define the patients' performance status using nutritional screening and comorbidity. Analyses were conducted using structural equation modeling (SEM).
ResultsOf the 1,968 eligible patients, 1,648 were analyzed. Univariable analyses documented the benefit of nutritional screening for LOS and MIS and ERAS (≥7 items) for LOS and complications; conversely, being male and comorbidities correlated with complications, while increased age and BMI correlated with worse outcomes. SEM analysis revealed that (a) the latent variable is explained by the use of nutritional screening (p0·004); (b) the variables were correlated (age–comorbidity, ERAS–MIS, and ERAS–nutritional screening, p < 0·001); and (c) their impact on the outcomes was based on direct effects (complications: sex, p0·001), indirect effects (LOS: MIS-ERAS-nutritional screening, p < 0·001; complications: MIS-ERAS, p0·001), and regression-based effects (LOS: ERAS, MIS, p < 0·001, nutritional screening, p0·021; complications: ERAS, MIS, p < 0·001, sex, p0·001). Finally, LOS and complications were correlated (p < 0·001).
ConclusionEnhanced recovery after surgery (ERAS), MIS, and nutritional screening are beneficial in surgical oncology; however, the inter-variable correlation is reliable, underlying the importance of the multidisciplinary approach.

背景
微创手术（Minimally Invasive Surgery, MIS）、加速康复外科（Enhanced Recovery After Surgery, ERAS）及术前营养筛查是当前用于降低术后并发症发生率与缩短住院时长（Length of Stay, LOS）的常用手段，但目前针对上述手段间的变量相关性研究尚少。本研究旨在明确大型胃肠道癌症患者队列中各变量间的相关性及其对临床结局的影响。

方法
本研究纳入2019至2020年间接受根治性胃肠道手术的连续性癌症患者进行分析。评估患者的年龄、体质量指数（Body Mass Index, BMI）、合并症、加速康复外科方案、术前营养筛查及微创手术方式，以明确其对术后30天并发症及住院时长的影响。同时量化变量间相关性，并基于营养筛查与合并症情况构建潜在变量以表征患者的功能状态，统计分析采用结构方程模型（Structural Equation Modeling, SEM）。

结果
本研究共纳入1968例符合入组标准的患者，最终纳入分析1648例。单因素分析显示，术前营养筛查可改善住院时长，包含≥7项内容的加速康复外科方案与微创手术均可同时缩短住院时长并降低并发症发生率；反之，男性性别与合并症与并发症发生风险升高相关，而年龄增长与体质量指数升高则与不良临床结局相关。结构方程模型分析结果显示：① 潜在变量可通过术前营养筛查的实施情况进行解释（p=0.004）；② 多个变量间存在显著相关性（年龄-合并症、加速康复外科-微创手术、加速康复外科-术前营养筛查，均p<0.001）；③ 各变量对临床结局的影响可分为直接效应（并发症：性别，p=0.001）、间接效应（住院时长：微创手术-加速康复外科-术前营养筛查，p<0.001；并发症：微创手术-加速康复外科，p=0.001）以及基于回归的效应（住院时长：加速康复外科、微创手术，p<0.001；术前营养筛查，p=0.021；并发症：加速康复外科、微创手术，p<0.001；性别，p=0.001）。最后，住院时长与并发症发生率呈显著相关（p<0.001）。

结论
加速康复外科、微创手术与术前营养筛查均对肿瘤外科治疗具有积极价值；然而，各变量间存在可靠的相关性，这凸显了多学科诊疗模式的重要性。