Study On The Relation Between The PH Value Of Gastric Juice And Ventilator Associated Pneumonia

Objective: To investigate the etiology,the outcome of drug senstivity and the incidence of ventilator-associated pneumonia(VAP),and the endogenous pathogenesis of VAP. To provide the elementary epidemiology data in order to prevent and cure the patients of VAP in intensive care unit(ICU) ,and the scientific information to formulate and adopt the prophylactic and controlling measure. To direct the use of antibiotic and lower the medical cost in curing the patients of VAP.Methods: Ninty-eight valid cases were collected in the ICU which were divided into two groups: VAP and non-VAP , messured the PH Value of Gastric juice and anylsed the bacterical culture results of gastric fluid,pharynx oralis and lower respiratory tract samples. Prospectively and dynamically, the relation between the PH Value of Gastric juice and the pathogenic bacteria type of gastric fluid,pharynx oralis bwtween two groups were observed and compared, the type and occurrence order and the information of drug sentivity were detected in samples from phargnx oralis,gastric fluid and lower respiratory tract after occuring VAP.The relation between the PH Value of Gastric juice and the gastric colonized bacteria or the no gastric colonized bacteria were compared, the results were analyzed statistically.Results: There were no significant differences in age sex APACHE between VAP group and non-VAP. The duration of mechanical ventilation in VAP group was longer than that of non-VAP. the gastric PH of gastric colonized bacteria was significant higher than that of no gastric colonized bacteria, the type of gastric colonized bacteria was affected by gastric PH. When the PH Value of Gastric juice was≤4,the gastric colonized bacteria were mainly Monilia and Gram positive bacilli, whereas the PH value of Gastric juice was >4,the isolation rate of Gram negative bacilli(GNB) which were mainly multidrug resistant extend spectrum Beta-lactamases bacilli in gastric cavity markedly increased. The isolation rate of VAP group was significant increased than that of non-VAP group. The occurrence of VAP was affected by the PH value of gasetric juice,the incidence of VAP when the PH value of gasetric juice >4 was higher than that of the PH value of gasetric juice≤4.the result of bacterial biochemical event and the spectrum of the bacteria sensitivity showed that the pathogenic bacteria of the lower respiratory tract of VAP were major GNB which were mainly multidrug resistant extend spectrum Beta-lactamases bacilli,homologized with the pathogenic bacteria of gastric juice.The colonized orders were usually gastral cavity→oropharyngeal→lower respiratory tract or gastral cavity→lower respiratory tract.Conclusion: The PH value of gasetric juice proved to be the major factor which influenced the colonization of bacteria especially GNB which were mainly multidrug resistant extend spectrum Beta-lactamases bacilli in gastric cavity;the reverse stomach→oropharyngeal→lower respiratory tract infection route existed in VAP patients,the PH value of gasetric juice advanced, the incidence of VAP was increased; In order to prevent VAP ,the change of the PH value of gasetric juice for the patients of MV in ICU might be dynamically monitored; During the process of prevention and cure of the stress ucler and stress associated upper gastrointestinal bleeding, sucralfate and other antiacids were used because it could not alter the PH value of gasetric juice; To cure the patients of VAP, the antibiotic drug sensitive to the GNB which colonized in the gastric cavity were used experiencely.