机械通气期间腹泻原因的探讨

目的 了解重症监护病房机械通气患者腹泻的原因、性质、探讨其处理对策和预防措施。方法 1998年1月－1999年12月呼吸监护室收住的56例机械通气超过48h，上机前无腹泻（稀便次数＞3次／d)的患者于机械通气当天开始行胃肠营养，分次从鼻胃管输注。胃肠泵控制速度在40－120ml/h，营养素经加热后进入胃管。所有患者上机期间均使用静脉抗生素等药物。结果 机械通气后，有33例（59％）患者发生呼吸机相关肺炎（VAP）；19例（34％）患者发生过用腹泻，腹泻平均持续13d。其中8例患者大便涂片中找到多量真菌孢子，3例同时找到菌丝，4例大便中杆菌明显减少，以球菌为主，其中3例患者大便中可见粪肠球菌；2例患者既有真菌又有球菌／杆菌比失调；9例腹泻患者大便常规及菌群正常，仅1例发生少量真菌孢子，经调整胃肠营养的温度及速度，腹泻在1－2d内消失。采用Logistic检验发现，腹泻的发生与VAP有关。结论 在胃肠营养输注条件最优化后，合理应用抗生素，预防及积极治疗VAP，可减少机械通气期间腹泻的发生并缩短腹泻的持续时间。

Diarrhea duing mechanical ventilation

Objective To identify the causes of diarrhea during mechanical ventilation.Methods We reviewed 56 cases, who have been mechanically ventilated for more than 48 hours, and also received both enteral and parental nutritional support in our RICU.Results 33 (57%) patients developed ventilator associated pneumonia. 19 (33%) patients suffered from diarrhea, lasted 13 days on average. Spores with large quantities were found in stools of 8 patients, with hypha in three patients. There was imbalance of bacteria in faeces in 4 cases, manifested by decreases in rods and increases in cocci, in which E. faecalis were present in 3 patients. 9 patients suffered from diarrhea with no evidence rate of abnormalities in their faeces. Diarrhea was treated by adjustment of food temperature and rate of feeding. it is confirmed by Logistic regression that diarrhea during mechanical ventilation was correlated with vertilator associated pneumonia (VAP).Conclusions Diarrhea in mechanical ventilated patients in our RICU were attributed mainly to improper administration of enteral nutrition, disturbances of the microenvironment of the intestines, including fungal infection, imbalance between coccus and rod, even E. faecalis colonization. Limitation of broad spectrum antibiotics administration, VAP control, and proper administration of formula are strongly recommended.