Analysis Of Etiological Characteristics And Clinical Significance Of Catheter Tip Culture

Objective: By analyzing the detection rate,distribution characteristics of pathogen and influencing factors in catheter tip culture,this paper provides a theoretical basis for clinically reducing and preventing catheter-related infections and guiding the early empirical treatment of catheter-related infections.Research methods: The specific method to research this issue is via collecting the information on patients with indwelling catheter(including endotracheal tubes,intravascular catheters and urinary catheters)in the First Affiliated Hospital of China Medical University from January 2016 to December 2017,the tips of the catheters were cultured when the catheters were replaced or removed,and the further information could be analyzed retrospectively containing general information,the site of catheter insertion,the result of microbial culture,CD4,hemoglobin,albumin,hemodynamic during catheterization,medical history,operation or trauma,use of antibiotics and hormones,prognosis and other relevant indexes of the patients.Results: 1.In 497 patients,the detection rate of pathogenic bacteria in endotracheal catheters tip culture was the highest(75%),followed by urinary catheters(41.9%),and the lowest detection rate in intravascular catheters(39%).The corresponding infections were CRBSI,CAUTI and VAP with the incidences: 26.5%,9.7% and 8.7% respectively,and the infection rate: 23.74/1000 catheter-days,8.62/1000 urinary catheter(UC)-days,and 6.97/1000 mechanical ventilator(MV)-days respectively.There was a statistically significant difference between the three groups(P< 0.05).Furthermore,the rate of infection was different is the different catheterization sites in intravascular catheters(P<0.05),and the infection rate was in descending order of the femoral venous catheter(16.56‰),internal jugular catheter(12.48 ‰),subclavian venous catheter(6.01 ‰)and PICC(3.16 ‰).2.Gram-negative bacteria were the main pathogens detected in the catheter tip culture.The detection rate was 39.09%,among which the top pathogens were Acinetobacter Bauman,Pseudomonas aeruginosa,Escherichia coli and Klebsiella pneumoniae.The detection rate of Gram-positive bacteria was 34.55%,ranking the second,mainly with Staphylococcus and Enterococcus.Besides,the detection rate of fungi was 26.36%,with Candida guilliermondii and Candida parapsilosis more commonly.Moreover,the distribution of pathogenic bacteria detected in catheter tip culture of different catheters types was different.Among them,the highest detection rate of intravascular catheters was Gram-positive bacteria.The detection rate of Gram-negative bacteria was the highest in endotracheal tubes,and urinary catheter detection of fungus is more common.3.Analysis of risk factors: The independent risk factors affecting catheter infection results were CD4,catheterization time,catheterization site,emergency and ICU catheterization.4.In the vascular intubation group,the infection rate of CRBSI was significantly increased from 9 to 14 days compared with the former group.While in the endotrachealtube and urinary catheter group,VAP and CAUTI were significantly increased when the catheterization time was more than 14 days.5.Prognostic analysis: The mortality rate of catheter culture negative group,catheter pathogen colonization group and catheter infection group gradually increased,however,the difference was not statistically significant(P>0.05).Conclusion: The results of catheter tip culture and catheter-related infection differ from different catheter types and catheterization sites.It is recommended to use PICC and to avoid femoral vein catheterization when patients requires intravascular catheterization.In etiology,Gram-negative bacteria were the main pathogens detected in the catheter tip culture.The detection rate of Gram-positive bacteria is the highest in intravascular catheters.In endotracheal tubes,Gram-negative bacteria are detected more frequently,while fungus are more conmmon in urinary catheter.The independent risk factors influencing catheter infection results were CD4,catheterization time,catheterization site,emergency and ICU catheterization.It is recommended endotracheal tubes and urinary catheters should be removed within 14 days and intravascular catheters should be removed within 8 days.