Supplementary Material for: Effects of Enteral Immunonutrition in Patients Undergoing Pancreaticoduodenectomy: A Meta-Analysis of Randomized Controlled Trials

<b><i>Background:</i></b> The effect of enteral immunonutrition (EIN) in patients undergoing pancreaticoduodenectomy (PD) is still doubtful. This meta-analysis aimed to assess the impact of EIN on postoperative clinical outcomes for patients undergoing PD. <b><i>Methods:</i></b> A literature search was carried out to identify all of the randomized controlled trials (RCTs) concerning the use of EIN for PD. Data collection ended on April 1, 2018. Pooled risk ratios (RRs) and the mean difference (MD) with a 95% CI were calculated using fixed effects or random effects models. The analyses were performed with RevMan 5.3.5. <b><i>Results:</i></b> Four RCTs with a total of 299 patients were included. Immunonutrition reduced the incidence of postoperative infectious complications (RR 0.58, 95% CI 0.37–0.92; <i>p</i> = 0.02) and shortened the length of hospital stay (MD –1.79, 95% CI –3.40 to 0.18; <i>p</i> = 0.03). Conversely, there were no significant differences in the incidence of overall postoperative complications (RR 0.81, 95% CI 0.62–1.05; <i>p</i> = 0.11), non-infectious complications (RR 0.94, 95% CI 0.69–1.28; <i>p</i> = 0.70) and postoperative mortality (RR 2.43, 95% CI 0.37–16.10; <i>p</i> = 0.36). <b><i>Conclusions:</i></b> EIN reduced postoperative infectious complications and shortened the length of the hospital stay; immunonutrition should be encouraged in patients undergoing PD.

<b><i>背景：</i></b> 肠内免疫营养（enteral immunonutrition, EIN）对接受胰十二指肠切除术（pancreaticoduodenectomy, PD）患者的疗效仍存在争议。本荟萃分析旨在评估EIN对接受PD患者术后临床结局的影响。<b><i>方法：</i></b> 开展文献检索以识别所有针对PD患者使用EIN的随机对照试验（randomized controlled trials, RCTs）。数据收集工作于2018年4月1日截止。采用固定效应模型或随机效应模型计算合并风险比（risk ratios, RR）与均数差（mean difference, MD）及95%置信区间（confidence interval, CI），所有分析均通过RevMan 5.3.5软件完成。<b><i>结果：</i></b> 共纳入4项RCTs，总计299例患者。免疫营养可降低术后感染并发症发生率（RR=0.58，95%CI：0.37~0.92；<i>p</i>=0.02），并缩短住院时长（MD=-1.79，95%CI：-3.40~0.18；<i>p</i>=0.03）。与之相对，术后总并发症发生率（RR=0.81，95%CI：0.62~1.05；<i>p</i>=0.11）、非感染性并发症发生率（RR=0.94，95%CI：0.69~1.28；<i>p</i>=0.70）及术后死亡率（RR=2.43，95%CI：0.37~16.10；<i>p</i>=0.36）均无显著统计学差异。<b><i>结论：</i></b> EIN可降低术后感染并发症发生率并缩短住院时长，因此应在接受PD的患者中推广使用免疫营养。