中链/长链甘油三酯早期肠内营养对烧伤患者蛋白质代谢的影响

目的：比较烧伤患者早期肠内喂养中链甘油三酯（MCT）／长链甘油三酯（LCT）与单独喂养LCT对蛋白质代谢的不同影响，探讨MCT／LCT改善烧伤后营养状态及可能机制。方法：选取30例烧伤总面积（TBSA）＞30％的烧伤患者，随机分为两组，一组为Fresubin 750MCT(F组），饲以含MCT／LCT的肠内营养制剂Fresubin 750MCT,一组为Nutrison(N)组，饲以只含LCT的肠内营养制剂Nutrison。于伤后24h内开始完全肠内营养支持，共支持10d。在伤后1－10 d观察了两组患者血清转铁蛋白、前白蛋白，尿－3甲基组氨酸排泄率及每日尿总氮的变化情况。结果：烧伤后机体蛋白分解增加，血清蛋白水平下降，F组患者血清转铁蛋白、前白蛋白较N组明显升高，尿总氮F组在伤后5，6，7，8，9,10d显著低于N组（P＜0．05或0．01）；伤后7，10dF组尿3－甲基组氨酸排泄率均显著低于N组（P＜0．01或0．05）。结论：含MCT／LCT的肠内营养制剂能通过有效地减轻烧伤后机体蛋白分解、提高血清蛋白水平，而改善烧伤患者营养状况。

Effects of early enteral nutrition containing medium and long-chain triglyceride on protein metabolism of burned patients

Objective To compare the effects of different early enteral nutrition formula (containing either MCT/LCT or LCT only) on protein metabolism of burned patients. Methods Thirty cases of burned patients injured by various causes with total burn surface area (TBSA) more than 30% were collected and randomized into two groups:enteral feeding with Fresubin 750MCT containing MCT/LCT as fat source (Group F); enteral feeding with Nutrison containing only LCT as fat source (Group N). All of 30 patients received isocaloric, isonitrogenous and isolipidic enteral feeding, which was started within 24 hours postburn and lasted for 10 days. The changes of serum concentration of transferrin and prealbumin were observed on postburn day (PBD) 1, 4, 7 and 10. Nitrogen in urine per day and excretion of 3 methylhistidine in urine on day 1, 7 and 10 postburn were observed as well. Results The patients in the Group F had an increased serum concentration of transferrin and prealbumin. Excretion of nitrogen in urine was decreased 5, 6, 7, 8, 9 and 10 days after burn and was significantly lower than that in the Group N ( P <0.05 or P <0.01). Excretion of 3 methylhistidine in urine was decreased at the postburn day 7 and 10 in the Group F and was significantly lower than that in the Group N ( P <0.01 or P <0.05). Conclusions An enteral compound diet containing MCT/LCT used in the early enteral feeding on burned patients can improve the status of protein metabolism of burned patients more effectively.