结直肠切除术后早期肠内营养的前瞻性研究

Early enteral nutrition after colorectal resections: a prospective clinical trial

目的 探讨结、直肠手术后早期肠内营养的可行性，比较肠内与肠外营养的代谢效应，并观察肠内营养对结肠粘膜组织学的影响．方法 结直肠术后随机分为早期肠内营养（ｅｎｔｅｒａｌ ｎｕｔｒｉｔｉｏｎ ，ＥＮ） 和全肠外营养（ＴＰＮ） 组，各１５ 例． ＥＮ 组术后２４ ｈ 内经鼻肠管滴注能全力（ｎｕｔｒｉｓｏｎ ｆｉｂｅｒ） ，ＴＰＮ 组经外周静脉进行，两组基本等热量，各７ ｄ ． 术前及术后８ ｄ 进行人体测量，生化监测、留取结肠粘膜标本行光镜及透射电镜观察，并比较肠功能恢复及住院费用等．结果 ＥＮ 组１５ 例均完成肠内营养计划，未发生吻合口瘘和腹腔感染． 两组术后体重、三头肌皮褶厚度、上臂周径、清蛋白均较术前略低（ Ｐ＜ ０－０１） ，两组总淋巴细胞计数、前清蛋白营养支持前后无显著差异（ Ｐ＞ ０－０５） ，转铁蛋白ＴＰＮ 组术后８ ｄ（２－３±１－１）ｇ／ Ｌ显著低于术前水平（３－４ ±１－６）ｇ／ Ｌ，Ｐ＜ ０－０１ ，而ＥＮ 支持组仍维持在术前水平． 碱性磷酸酶ＴＰＮ 组术后（１６３±１２０）Ｕ／ Ｌ高于术前（１２５ ±９７）Ｕ／ Ｌ，Ｐ＜ ０－０５ ，而ＥＮ 支持前后无明显改变，术后乳酸脱氢酶ＴＰＮ 组（６３５ ±３７７） Ｕ／ Ｌ高于ＥＮ 组（４１８ ?

AIM To evaluate the feasibility of early postoperative enteral nutrition (EN) in colorectal surgery and compare the metabolic effects and histologic changes of colonic mucosa following EN or total parenteral nutrition (TPN). METHODS Patients undergone open elective colorectal resections were randomized to either early EN or control (TPN) group. Fifteen patients in EN group had a nasal jejunal tube inserted during the operation. The enteral feeding with a formula containing fiber started within the first 24 hours postoperatively and continued for consecutive 7 days. The full load of EN provided 0 18*!ng/*!(kg·d) and 104 5*!kJ/*!(kg·d) of non protein energy. Fifteen patients in control group received total parenteral nutrition via peripheral vein postoperatively and provided 0 10*!ng/*!(kg·d) and 101*!kJ/*!(kg·d) of non protein energy for 7 days. Anthropometric, biochemical parameters and visceral functions were monitored. Colonoscopic examination with mucosa biopsy were taken in 6 patients of EN group and 4 patients of parenteral nutrition (PN) group preoperatively and followed up for 8 days postoperatively. The microstructure of the colonic mucosa was studied. RESULTS Patients in each group were well matched with sex, age, type and duration of operations. All patients in EN group tolerated the early feeding. Total lymphocyte and prealbumin level maintained stable after the nutrition support in both groups. Serum transferrin maintained stable in EN group, however, decreased significantly in TPN group. By the end of the study cumulated nitrogen balance in EN and TPN groups was ( -19 2 ±15 7) *!gN/*!7*!d and (-27 6±12 4) *!gN/*!7*!d , respectively ( P >0 05). On the 8th day the serum level of lactate dehydrogenase (LDH) was significantly higher in TPN group than that of EN group (635±376 vs 418±147, P <0 05 ). An increased alkaline phosphatase (AKP) level was observed after TPN support, but not in EN group. No difference was found in total bilirubin and transaminase level in the two groups. No bowel anastomosis leakage was found in both groups. There were no statistical differences in wound healing, infective complications and duration of hospitalization between the two groups. The overall cost of enteral nutrition was significantly lower than that of TPN group ( P <0 05) . The audible bowel sounds and bowel movement recovered earlier in EN group than that in the control group ( P <0 05) . Histologic examination showed the colonic mucosa thickness and glands density decreased after seven days of TPN, but unchanged after EN. Postoperatively no significant changes were observed in ultrastructure of the colon epithelial cell in the two groups except for reduced microvilli, less mucus secretion and water transport in TPN group. CONCLUSION The early postoperative enteral nutrition was well tolerated in the patients undergone colorectal surgery. In comparison with TPN the metabolic effect was similar in EN with less disturbance of liver function. The early enteral feeding with formula containing fiber may help to maintain the bowel functions and gut integrity.