Pathogenic Characteristics And Prognostic Factors Analysis Of Bloodstream Infection In ICU Patients

BackgroundBloodstream infection is serious infectious diseases with high morbidity and mortality.With the widespread use of broad-spectrum antibiotic,more and more multidrug-resistant organisms are appearing,and the mechanism of multidrug-resistant is complex and variable,which has attracted worldwide attention.The problems of bloodstream infections and multidrug-resistant organisms are particularly severe in intensive care units(ICU),making clinical treatment difficult.In order to prevent the incidence of multidrug-resistant organisms,countries have established the drug resistant bacteria surveillance network,but the distribution of pathogens vary from regions,regional bloodstream infection and the clinical characteristics of multidrug-resistant organisms need further study.PurposeThe purpose of this study was to analyze the pathogenic characteristics of bloodstream infection in ICU and the related factors for poor prognosis of patients,as well as the related risk factors for the occurrence of multi-drug resistant organisms in bloodstream infection in our hospital,so as to provide a basis for the prevention of bloodstream infection and guide the rational use of antibiotics in ICU.MethodsThe hospitalization data of patients with bloodstream infection in the ICU of the First Affiliated Hospital of Xiamen University from January 2016 to December 2020 were retrospectively analyzed,including clinical data,laboratory indicators,and etiological results,SOFA score,Pitt bacteremia score,etc.According to the blood culture and drug sensitivity results,the patients were divided into sensitive bacteria group and multiple drug resistant organisms group.Univariate analysis was conducted for statistically significant variables,and logistic regression was used to analyze the independent risk factors for multidrug-resistant organisms bloodstream infection.According to their prognosis,Patients were divided into survival group and death group.Cox regression model was used to analyze prognostic factors and identify independent risk factors related to death of patients with bloodstream infection.Results1.Etiological characteristics of bloodstream infections in ICU:360 patients included in this study.There were 231 strains of Gram-negative bacteria(64.2%),97 strains of Gram-positive bacteria(27.0%)and 32 strains of fungi(8.8%).The top three is e.coli(77 strains,21.4%),klebsiella pneumoniae(69 strains,19.2%)and coagulase negative staphylococcus(37 strains,10.3%).The proportion of multi-drug resistant bacteria in Gram-negative strains was 51.5%,and that in Gram-positive strains was 47%.The overall drug resistance rate showed an upward trend.By comparing the relationship between bloodstream infection and primary infection,it was found that Klebsiella pneumoniae was the first pathogenic bacteria in abdominal tract infection combined with bloodstream infection,and Acinetobacter baumannii,Coagulase-negative Staphylococcus and Candida were the first three pathogenic bacteria in central line-associated bloodstream infection.2.Analysis the risk factor of Multi-drug resistant organisms bloodstream infections:Univariate logistic regression analysis of risk factors are as list.surgical operation before bloodstream infections(P<0.001),central venous catheter(P=0.002),arterial catheter(P=0.001),mechanical ventilation(P<0.001),continuous blood purification therapy(P=0.012),antimicrobial application(P=0.001),and Pitt bacteremia score(P=0.016).Results of multivariate analysis:patients had a history of surgery within one mouth before bloodstream infection(OR 1.98,95%CI[1.27,3.11],P=0.003),mechanical ventilation within one mouth before bloodstream infection(OR 1.76,95%CI[1.08,2.87],P=0.022),and length of hospital stay before bloodstream infection(OR 1.02,95%CI[1.0,1.05],P=0.047).Surgery,mechanical ventilation,and long hospital stay were all independent risk factors for bloodstream infection with multidrug-resistant organisms.3.Analysis of prognostic factors of bloodstream infection:There are 8 independent risk factors related to death in bloodstream infection:BMI(OR 0.92,95%CI[0.87,0.98],P=0.005)、CKD(OR 4.81,95%CI[2.32,9.95],P<0.001),SOFA score(OR 1.17,95%CI[1.09,1.25],P<0.001),Pitt bacteremia score(OR 1.19,95%CI[1.08,1.30],P<0.001),inflammatory markers CRP(OR 1.01,95%CI[1.00,1.01],P<0.001),fibrinogen(0.84[0.73,0.98],P=0.028),pH(OR 0.02,95%CI[0.00,0.21],P=0.002)in blood gas analysis,MODS(OR 3.21,95%CI[1.79,5.77],P<0.001)were complicated.In our study,the multi-drug resistant organisms had little effect on the case mortality of patients with bloodstream infection,but the case mortality was higher for patients with more basic diseases and multiple organ dysfunction combined with internal environment disorders.Conclusions1.The top 5 pathogens of bloodstream infection in ICU ward were Escherichia coli,Klebsiella pneumoniae,coagulase-negative Staphylococcus,Acinetobacter baumannii and Enterococcus.Gram-negative bacteria were the majority of pathogenic bacteria,and the proportion of drug-resistant bacteria showed a gradually increasing trend.2.Independent risk factors of multidrug-resistant bacteria in bloodstream infections included surgery,mechanical ventilation,and a long hospital stay.3.The factors affecting the prognosis of patients with bloodstream infection include chronic kidney disease complicated with multiple organ failure and acidosis.This study provides a reasonable basis for the prevention and prediction of bloodstream infection,and has important guiding significance for the initial antibiotic application of patients with bloodstream infection in ICU.