目的 比较两种脂肪乳剂不同肠外营养时间对早产儿临床结局的影响。 方法 将符合纳入标准的早产儿随机分为两组：中/长链脂肪乳（medium/long-chain triglyceride fat emulsion，简称MCT/LCT）组和多种油脂肪乳［含大豆油、中链甘油三酯、橄榄油、鱼油（soybean oil, medium-chain triglycerides, olive oil, and fish oil），简称SMOF］组。根据肠外营养持续时间（15~21 d、22~28 d、≥29 d）分层分析，比较两组早产儿的临床特征、营养状况、生化指标和临床结局。 结果 与MCT/LCT组相比，SMOF组肠外营养持续时间分别为15~21 d、22~28 d、≥29 d的早产儿住院期间甘油三酯的峰值水平均较低（P<0.05）。logistic回归趋势性分析显示，随着肠外营养时间延长，MCT/LCT组早产儿肠外营养相关性胆汁淤积症（parenteral nutrition-associated cholestasis, PNAC）及支气管肺发育不良（bronchopulmonary dysplasia, BPD）的发生风险均明显增高（P<0.05），脑损伤的发生风险无明显变化（P>0.05）；SMOF组早产儿随着肠外营养时间延长，PNAC及BPD的发生风险均无明显变化（P>0.05），而脑损伤的发生风险明显降低（P=0.006）。 结论 与MCT/LCT相比，SMOF具有较好的脂质耐受性；随着肠外营养持续时间延长，SMOF不增加PNAC、BPD的发生风险，且对脑损伤具有保护作用，表明在需要长期肠外营养的早产儿中使用SMOF优于MCT/LCT。

Objective To compare the impact of two types of fat emulsion on clinical outcomes in preterm infants with varying duration of parenteral nutrition (PN). Methods Preterm infants meeting the inclusion criteria were randomly assigned to two groups: medium/long-chain triglyceride fat emulsion (referred to as MCT/LCT) group or multi-oil fat emulsion (containing soybean oil, medium-chain triglycerides, olive oil, and fish oil; referred to as SMOF) group. The infants were stratified into groups based on the duration of PN (15-21 days, 22-28 days, and ≥29 days). Clinical characteristics, nutritional status, biochemical indicators, and clinical outcomes were compared between the two groups. Results Compared with the MCT/LCT group, the SMOF group had lower peak levels of triglyceride during the hospital stay in preterm infants with PN of 15-21 days, 22-28 days, and ≥29 days, respectively (P<0.05). Logistic regression trend analysis showed that with a longer duration of PN, the risk of parenteral nutrition-associated cholestasis (PNAC) and bronchopulmonary dysplasia (BPD) significantly increased in the MCT/LCT group (P<0.05), while the risk of brain injury did not significantly change (P>0.05). In the SMOF group, the risks of PNAC and BPD did not significantly change with a longer duration of PN (P>0.05), but the risk of brain injury significantly decreased (P=0.006). Conclusions Compared to MCT/LCT, SMOF have better lipid tolerance. With a longer duration of PN, SMOF does not increase the risks of PNAC and BPD and had a protective effect against brain injury. This suggests that in preterm infants requiring long-term PN, the use of SMOF is superior to MCT/LCT.