【作者】 张力；

【导师】 王燕；

【作者基本信息】 天津医科大学 ， 内科学， 2008， 硕士

【摘要】 目的:①探讨胃内细菌定植在慢性阻塞性肺病(COPD)机械通气患者呼吸机相关性肺炎(VAP)发病机制中的作用;②探讨COPD机械通气患者胃液pH值、SIgA和TBA水平对其胃内细菌定植的影响;③探讨抑酸剂或黏膜保护剂的使用,营养支持类型对COPD机械通气患者胃液pH值、SIgA和TBA水平的影响。为预防COPD机械通气患者VAP的发生提供依据。方法:对35例COPD行机械通气患者,采用半定量培养法对下呼吸道、胃液、咽拭子标本进行细菌学检测;采用双抗体夹心放免法测定胃液SIgA水平;采用循环酶法测定胃液TBA水平;采用精密pH试纸测定胃液pH值;记录抑酸剂或黏膜保护剂的使用,营养支持类型,评价VAP发生情况。数据以SPSS13.0统计软件进行处理。结果:①35例患者121份胃液标本中有21例(60%)40份(33.06%)发生胃腔细菌定植,共分离菌株45株,主要为鲍曼不动杆菌、肺炎克雷白杆菌、铜绿假单胞、大肠埃希菌和嗜麦芽窄食单胞菌等。其中16例发生VAP(16/21),高于未定植组(5/14),差别均有统计学意义(p＜0.05)。其中6例(17.14%)6株病原菌出现胃腔→口咽部→下呼吸道的定植次序,且对比其药敏谱完全相同,表明其可能具有同源性。②胃腔细菌定植组胃液pH(5.65±1.03)和TBA(57.06±54.75μmol/L)均高于无定植组(4.56±1.51、25.36±16.62μmol/L)(p＜0.01),胃液细菌定植组奥美拉唑使用(22/40)多于无定植组(28/81)(p=0.032),胃液细菌定植组SIgA(12.67±20.1μg/L)高于无定植组(12.18±14.22μg/L),但差别无统计学意义(p＞0.05)。③使用奥美拉唑的两组胃液pH(A组5.50±0.69、B组6.32±0.57)显著高于使用磷酸铝的两组(C组3.30±0.67,D组4.23±1.41),差别有统计学意义(p＜0.01),而在使用奥美拉唑的两组和使用磷酸铝的两组内(即A组与B组间,C组与D组间)胃液pH值差别无统计学意义(p＞0.05);各组胃液TBA(A组43.42±58.94μmol/L,B组31.78±23.18μmol/L,C组20.14±12.86μmol/L,D组36.39±30.25μmol/L)差别均无统计学意义;应用TPN两组胃液SIgA(A组3.50±5.13μg/L、C组1.97±0.896μg/L)显著低于应用EN的两组(B组24.27±22.30μg/L,D组13.81±15.45μg/L),差别有统计学意义(p＜0.01),而在应用TPN的两组和EN的两组内(即A组与C组间,B组与D组间)胃液SIgA水平差别无统计学意义(p＞0.05)。④胃液pH与TBA(r=0.175,P=0.055)、pH与SIgA(r=0.169,P=0.064)、TBA与SIgA(r=0.094,P=0.307)均不存在相关性。结论:①COPD机械通气发生VAP患者中部分胃液、咽拭子和下呼吸道标本的培养结果出现致病菌的胃腔→口咽部→下呼吸道的逆向定植次序,验证了COPD机械通气患者胃肠道定植菌逆行与吸入是VAP的感染途径之一。②COPD机械通气患者胃液pH增高是胃内细菌定植的危险因素,使用奥美拉唑较磷酸铝因升高胃液pH而增加了胃内细菌定植的危险性,因此提示使用磷酸铝对VAP的发生有保护作用。③COPD机械通气患者胃液pH普遍偏高,可能与其疾病状态、鼻饲、年龄和胃十二指肠返流等因素有关。④COPD机械通气患者接受TPN可导致胃液SIgA水平降低,但SIgA水平既受营养类型的影响,同时也受感染等多方面因素影响,胃内细菌定植组与未定植组胃液SIgA水平未显示出差异。⑤胆汁返流是COPD机械通气患者胃内细菌定植的危险因素,胃液TBA与pH无直接相关性。更多还原

【Abstract】 Objective:In order to provide some clues to keep the chronic obstructive pulmonary disease(COPD)patients undergoing mechanical ventilation away from ventilator associated pneumonia(VAP),we set out to investigate:①the part the intragastric bacteria plays in the pathogenesis of VAP in COPD patients,②the influences of the physiochemical features of the gastric fluid,including pH value,SIgA and TBA level on the colonization of the intragastric bacteria and③the effects of acid inhibitors, mucosal protective agents and the type of nutrition support on the above mentioned features of the gastric fluid of the mechanical ventilated COPD patients.Methods:35 COPD patients undergoing mechanical ventilation were enrolled in our study.Bacteriological examination was made for the samples of lower respiratory tract,gastric fluid and pharyngeal swab by means of semi-quantitative cultivation. SIgA and TBA level in the gastric fluid was measured by means of double antibody sandwich radiation immunological test and enzymatic cycling assay,respectively.The pH value of the gastric fluid was determined by precision pH test paper.The administration of acidic inhibitor,mucosal protective agents and the type of nutritious support was recorded,and the occurrence of VAP was assessed.All the experimental data were processed and analyzed by SPSS13.0 statistic software package.Results:①Of all the 121 gastric fluid samples obtained from the 35 patients, intragastric bacteria colonization was spotted in 40 samples belonging to 21 cases. Totally,45 bacterial strains were isolated,which were mainly Acinetobacter baumannii,Klebsiella pneumoniae,Pseudomonas aeruginosa,Escherichia coli and Stenotrophomonas maltophilia.Among all these colonized cases,16(16/21) developed VAP,which was significantly higher than the non-colonized group(5/14, p＜0.05).In 6 cases,6 strains manifested a colonization order of gastric cavity, oropharynx and lower respiratory tract.All the colonies obtained from various positions share the same antibiotic sensitive spectrum,indicating the homogeneity among them.②The pH value and TBA level of the gastric fluid from the colonized group(5.65±1.03 and 57.06±54.75μmol/L,respectively)was significantly higher than that of the non-colonized group(4.56±1.51 and 25.36±16.62μmol/L,respectively) (p＜0.01).The frequency of omeprazole administration in the colonized group(22/40) was higher than that of the non-colonized group(28/81,p=0.032).The SIgA level in the gastric fluid of the colonized group(12.67±20.1μg/L)was higher than that of the non-colonized group(12.18±14.22μg/L),although the difference was statistically insignificant(p＞0.05).③Significant difference was spotted between the pH value of the gastric fluid from the 2 omeprazole treatment groups(group A,5.50±0.69;group B,6.32±0.57)and the 2 non-omeprazole treatment groups(group C,3.30±0.67;group D,4.23±1.41)(p＜0.01).No significant difference was found within the 2 omeprazole treatment groups and the 2 non-omeprazole treatment groups(p＞0.05).There was no significant difference among the four groups in TBA level,which was 43.42±58.94, 31.78±23.18,20.14±12.86,and 36.39±30.25μmol/L for group A,B,C and D, respectively.The SIgA levels in the gastric fluid of the 2 TPN groups(group A, 3.50±5.13μg/L and group C,1.97±0.896μg/L)were significantly lower than those of the 2 EN groups(group B,24.27±22.30μg/L and group D,13.81±15.45μg/L) (p＜0.01),while no significant difference existed within the 2 TPN groups and the 2 EN groups(p＞0.05).④No correlations had been spotted between pH and TBA (r=0.175,P=0.055),pH and SIgA(r=0.169,P=0.064)and TBA and SIgA(r=0.094, P=0.307)in the gastric fluid samples.Conclusions:①The positive cultivation results of pathogenic bacteria in the gastric fluid,pharyngeal swabs and the lower respiratory tract samples revealed a colonization order of gastric cavity,oropharynx and lower respiratory tract and further demonstrated that retrogradation and aspiration was one of the infection routes of VAP in mechanical ventilated COPD patients.②Higher pH value of gastric fluid was a risk factor of intragastric bacteria colonization and omeprazole could increase the risk of the colonization by elevating this index,which indicated that compared with omeprazole,mucosal protective agent aluminum phosphate could provide more protective effects against VAP.③The gastric fluid pH value of the mechanical ventilated COPD patients trended to be much higher,which could be attributed to the influential factors such as morbid state,nasogastric feeding,age and gastroduodenal reflux.④TPN could decrease the SIgA level in the gastric fluid of mechanical ventilated COPD patients.However,since the SIgA level was affected by not only the type of nutrition support but also other factors such as infection,no difference had been spotted between the colonized and the non-colonized groups.⑤Bile reflux was a risk factor of intragastric bacteria colonization.No correlation existed between TBA level and pH value in gastric fluid.更多还原