Analysis Of Risk Factors And Immune Function Of Ventilator-associated Pneumonia Patients

Objective(1)To explore clinical risk factors and preventive strategies of ventilator associated pneumonia(VAP)caused by Extended-Spectrum?-lactamases-producing(ESBLs)Enterobacteriaceae in general intensive care unit,in order to improve clinical prevention consciousness and reduce its incidence rate.(2)To investigate the relationship between immune function status and ventilator-associated pneumonia in critically ill patients by studying the changes of peripheral blood T cell subsets and NK cell levels in patients with mechanical ventilation.Methods Part ? Retrospective analysis the clinical data of whom met the critical of ventilator associated pneumonia from four thousand six hundred and forty-three patients with mechanical ventilation in general intensive care unite from January 2013 to December 2016.The ESBLs(+)VAP group is case group and ESBLs(-)VAP is control group.The clinical data Include the patient's general condition,state of consciousness,the basic diseases of the lungs,sepsis,shock,clinical scores,albumin level,mechanical ventilation time,ICU hospitalization time,antibiotic use time,antibiotic type,whether to use glucocorticoid,invasive operation,treatment outcome and so on.Multi-factor logistic regression analysis was used to analyze the risk factors in the univariate analysis,While analyzing the characteristics of pathogens.Part ? Through the prospective study,120 cases of surgical ventilation were analyzed in the Department of Intensive care unit,General Hospital of Tianjin Medical University from June 2016 to December 2016.Fifty-three patients were strictly selected as the final study object according to the inclusion criteria.Flow cytometry was used to observe the changes of T cell subsets and NK cell levels in peripheral blood at admission,48 hours and 1 week,and SPSS software was used for data analysis.Results Part ?(1)There are 105 patients with VAP In 4643 patients with mechanical ventilation,the incidence rate of 2.3%,of which 23 cases of ESBLs(+)bacteria VAP,the incidence was 21.9%.12 cases was dead in the ESBLs(+)bacteria VAP patients,mortality rate of 52.2%.30 cases was dead in the ESBLs(-)bacteria VAP,the mortality rate of 36.6%.(2)A total of 133 pathogens were cultured in VAP patients with lower respiratory tract secretions.123 strains Gram-negative bacteria were detected in Gram-negative bacteria,accounting for 92.4%,Gram-positive bacteria was 7 strains,(5.3%),3 fungi(2.3%).The top three pathogens were 43 strains(42.3%)of Klebsiella pneumoniae,34 strains(25.6%)of Acinetobacter baumannii and 14 strains(10.5%)of Pseudomonas aeruginosa.(3)Univariate analysis showed that a variety of factors predictive value,including the basic diseases of the lungs,coma,bronchoscopy,tracheotomy,ICU hospital stay,serum albumin levels,mechanical ventilation ? 5 days,antibiotics> 2,antibiotics Days(P <0.05).Further multivariate logistic regression analysis was performed on a statistically significant single factor found coma(OR = 4.61),albumin level(OR = 0.325),mechanical ventilation time ?5 days(OR = 5.262),antibiotics> 2(OR = 5.061)were independent risk factors for ESBLs(+)Enterobacteriaceae VAP.Among them,the lower the level of albumin the higher the risk of infection.Part ?In this study,we collected a total of 53 patients with severe ventilation and more than one week of mechanical ventilation from June 2016 to December 2016.Among them,22 patients were diagnosed with VAP and 31 patients without VAP were treated as controls.There was no significant difference in age and sex between the two groups.The mortality rate of VAP group was 22.7%,the death rate of non-VAP group was 9.7%,the mortality rate of VAP group was higher than that of non-VAP group(P <0.05).Compared with the two groups,the ventilation time of VAP group was significantly increased(15.5±6.2,11.3±4.3)day,and the hospitalization time was significantly prolonged(18.8±9.7,15.6±6.8)day(P <0.05).At 48 hours and 1 week,the percentage of NK cells in VAP group was(10.02 ± 5.65,12.23 ± 5.87)%,which was significantly lower than that in non-VAP group(13.37 ± 8.13,16.06 ± 6.22)%(P <0.05).At one week of mechanical ventilation,Lymphocyte count was significantly lower than that in non-VAP group(P <0.05).The percentage of CD8 + T cells in VAP group(27.33 ± 6.32)% was significantly higher than that in non-VAP group(23.81 ± 5.67)%.The results showed that VAP group was in immunocompromised state after 48 hours of mechanical ventilation,especially at 1 week,which was prone to complicated infection of various bacteria,and the possibility of VAP was significantly increased.Conclusions(1)Gram-negative bacilli is the main pathogen of VAP,the first three pathogens followed by Klebsiella pneumoniae,Acinetobacter baumannii,Pseudomonas aeruginosa,Enterobacter spp.VAP pathogen mainly is Klebsiella pneumoniae.(2)ESBLs-VAP was associated with a variety of risk factors,including coma,hypoproteinemia,mechanical ventilation time ? 5 days,antibiotics> 2 kinds of ICU in patients with VAP ESBLs infection occurred in the independent predictors of E.coli infection.(3)Critically ill patients prone to malnutrition,after ventilating 48 hours with low immune function,especially at one week,are more prone to ventilator-associated pneumonia.(4)The morbidity of VAP patients with low nutritional status was significantly increased,and the duration of mechanical ventilation and ICU hospitalization were significantly prolonged.