双歧杆菌对机械通气新生儿呼吸道和胃肠道的影响

Effects of bifidobacteria on respiratory and gastrointestinal tracts in neonates receiving mechanical ventilation

目的观察双歧杆菌对机械通气新生儿呼吸道和胃肠道的影响。方法将机械通气新生儿随机分为观察组(n=38)和对照组(n=43),观察组在机械通气后第2天开始鼻饲双歧杆菌1粒/d,连用7 d,对照组不予干预。观察两组胃液pH、胃定植菌、喂养不耐受、体重增加、呼吸机相关性肺炎(VAP)发生比率及病原菌与胃定植菌同源性等情况。结果观察组第3、5天及第7天胃液pH≤3的比例均明显高于对照组(P<0.01),而第5天及第7天胃细菌定植率均明显低于对照组(P<0.01)。观察组喂养不耐受和VAP发生比例均低于对照组(P<0.05,P<0.01),同时观察组VAP病原菌与胃定植菌同源率显著低于对照组(P<0.01)。两组体重日增加量差异无统计学意义(P>0.05)。结论双歧杆菌可降低胃酸度,减少胃定植菌和喂养不耐受发生,可间接阻断胃-口咽-呼吸道感染途径,从而减少VAP的发生。

Objective To study the effects of bifidobacterium on respiratory and gastrointestinal tracts in neonates receiving mechanical ventilation. Methods The eligible neonates were randomly assigned into two groups： observed（n=38） and control（n=43）.The observed group was given bifidobacteria daily（one capsule per time,for 7 days） by nasal feeding from the next day after mechanical ventilation.Gastric pH,gastric bacteria colonization,feeding intolerance,weight gain,the incidence of ventilator-associated pneumonia（VAP）,and the homology between the bacteria isolated from intra-gastric colonization with those causing VAP were observed. Results The incidence of gastric pH≤3 in the observed group was significantly higher than that in the control group 3,5 and 7 days after mechanical ventilation（P0.01）.The rate of gastric bacteria colonization in the observed group was significantly lower than that in the control group 5 and 7 days after mechanical ventilation（P0.01）.The incidences of feeding intolerance and VAP in the observed group were significantly lower than those in the control group（P0.05,P0.01,respectively）.The rate of homology of the bacteria isolated from intra-gastric colonization with those causing VAP in the observed group was significantly lower than that in the control group（P0.01）.There were no significant differences in the weight gain between the two groups. Conclusions Bifidobacterium can decrease gastric pH,gastric bacteria colonization and feeding intolerance,thus blocks the infection route ＂stomach-oropharynx-respiratory tract＂ indirectly and decreases the incidence of endogenous VAP in neonates receiving mechanical ventilation.