Epidemiological Characteristics And Clinical Research Of Ventilator-associated Pneumonia From Single Center

BackgroundAs the most common nosocomial infections of critical patients and one of the severe complications in patients with mechanical ventilation(MV),Ventilator-associated pneumonia(VAP)is a subset of Hospital-acquired pneumonia(HAP).The latest Infectious Diseases Society of America(IDSA)guidelines for the diagnosis and management of HAP/VAP define VAP as pneumonia that arises at least 48 h after endotracheal intubation.Given the high morbidity and mortality of VAP,it could significantly increase the in-hospital mortality,length of intensive care unit(ICU)stay,and financial burden of the patients.In recent years,multi-drug resistant bacteria(MDR)has become an important pathogen of nosocomial infection.It is becoming more and more difficult to treat gram-negative bacilli(GNB)infection in hospital,and how to diagnose VAP quickly and effectively.To ensure the safety of patients / medical workers and to control and prevent the spread of multi-drug resistant bacteria has become a key issue in the field of critical medicine.ObjectivesTo analyze retrospectively the clinical data of patients undergoing MV,summarize the morbidity,pathogens distribution in sputum culture,and the resistance profile of multidrug-resistant pathogens,and to explore the risk factors for and clinical outcomes of VAP in children.MethodsClinical data were collected from patients undergoing MV for at least 48 h in the ICU of a tertiary care teaching hospital in North Henan region from January 1,2013 to December 31,2016;based on the VAP diagnostic criteria of Chinese Society of Critical Care Medicine,the types and MDR profile of pathogens detected in sputum cultures were analyzed for patients with VAP.Patients in the Pediatric Intensive Care Unit(PICU)who met the inclusion criteria were assigned to the patient(VAP)group or control(non-VAP)group;statistical analyses were performed on patient age,sex,surgeries,number of endotracheal intubations,duration of MV,length of hospital stay,conscious state,as well as the application of large-dose gamma-globulin,glucocorticoids,and antiacids,etc.,so as to explore the risk factors for and clinical outcomes of VAP in children.ResultsThe proportion of patients undergoing MV was 17.23% in our hospital overall and19.59% in our PICU;the morbidity of VAP was 7.78% overall and 8.13% in our PICU.Among patients in the PICU,the mortality was16.13% in the 22 patients in VAP group,and 4.62% of the 158 patients in non-VAP group.A total of 341 isolates of pathogens were detected in the sputum cultures of the VAP patients,including 326 MDR isolates,accounting for the drug resistance rate of 95.60%.280 isolates were GNB,accounting for 82.11% of any isolates,and were primarily A.baumannii,P.aeruginosa,K.pneumoniae,and E.coli;22 isolates were gram-positive bacterial(GPB),accounting for 6.45% of any isolates,and were primarily Methicillinresistant S.aureus and S.pneumoniae.The resistance rates of A.baumannii to the antibiotics including Cefazolin and Aztreonam were as high as 100%,and A.baumannii was sensitive to the antibiotics including Moxifloxacin and Chloramphenicol;P.aeruginosa was sensitive to the antibiotics including Ceftazidime,Moxifloxacin;K.pneumoniae was sensitive to the antibiotics including Meropenem;the resistance rates of S.aureus to the drugs includingVancomycin and Linezolid were low;S.pneumoniae has a high sensibility to the drugs of Vancomycin and Linezolid.Differences in patient age,sex,conscious state,and use of antiacids showed no statistical significance for VAP(P>0.05);surgeries,number of endotracheal intubations,duration of MV,and length of hospital stay were shown to be independent risk factors for VAP;large-dose gamma-globulin were shown to be protective factors for preventing VAP in children.ConclusionsThe morbidity of VAP in our hospital is lower than the domestic and international average levels,and presents a tendency towards decreasing year by year;the morbidity of VAP is higher in children than in adults,requiring sufficient attention of clinical physicians.The pathogens detected in sputum cultures of VAP patients are primarily GNB;resistance to antibiotics varies significantly across different pathogens,along with multistrain resistance.Clinical physicians may select initial antibiotics empirically based on the distribution and drug resistance profile of the local pathogens.Surgeries,repeated tracheal intubations,duration of MV,and length of hospital stay are independent risk factors for VAP;glucocorticoids and large-dose gamma-globulin are protective factors for preventing VAP,which allows PICU physicians to introduce early interventions,thus reducing the morbidity and mortality of VAP.