肠外营养临床有效性的大样本临床研究与系统评价

肠外营养（PN）的发展推动了临床营养的进步，但过度应用可能造成的不良反应已引起关注，1991年美国VA研究发现，PN对无严重营养不良的患不仅无益，反而可能有害。2001年美国胃肠病学会运用循证医学方法对PN临床有效性进行了评价。合并所有纳入研究的总Meta分析发现，与空白对照相比，PN对死亡率和总并发症发生率无影响。但感染率明显较高。进一步的亚组分析发现PN的疗效与患类型有关。对择期术后患PN能降低并发症，最近我们基于高质量中研究的Meta-分析也发现，较之PN，使用肠内营养（EN）患的肝功能受影响更少，并有助于节省费用，虽然上述证据提示EN有较多优势，但患方面的需求也在很大程度上决定营养支持方式的选择。临床医生需要结合患和客观证据两方面考虑对营养支持途径的选择。

The Validity of Parenteral Nutrition: Evidence from Large Clinical Trial and Systematic Review

The development of parenteral nutrition promoted the evolution of clinical nutrition,but with excess using of PN many adverse reactions arose.In1991 ,The Veterans Affairs Total Parenteral Nutrition Cooperation published its stud y in New England Journal of Medicine.They found patients without severe malnut rition could not benefit from PN support,on the contrary,the harmful effects were observed.As the controversy arose,systematic review was used for clarify the issue.In2001,American Gastroenterology Association(AGA)conducted a systematic review about PN.In the Meta-analysis which pooled all the inclusion trials,the results indicated that comparing with the placebo-controled the PN intervention related with higher infectious morbidity although there were no sig nificant difference on mortality and total morbidity.Further sub-group analysi s found that the effects of PN related with patients' type.In the selectively operated patients,PN support reduced post-operative complications.Lastly,our Meta-analysis based on high quality Chinese RCTs revealed that EN had less imp act on liver function,and decreased the cost of treatment.Hence the current e vidences demonstrated that EN was more reasonable then PN,but the decision of intervention was affected by the special requirements of patients.Scolapio et a l investigated patients' favor on EN and PN,the results indicated the factors related on the accessibility on PN and EN.Clinicians should intergrate the pati ents' subjective requests and the Objective requirements when deciding the acce ss for nutrition support.route should be used.