Distribution And Drug Resistance Analysis Of PICC-related Bloodstream Infections In Intensive Care Unit

Objectives: To analyze the distribution characters and resistance rates of indigenous bacteria of Catheter-related bloodstream infection of Peripherally Inserted Central Catheter(PICC) of the patients in intensive care unit between January 2011 and December 2014; to help diagnosing Catheter related blood stream infection; and to supply scientific evidence for clinical diagnosis, prevention and treatment. Further more, the study is to supply reference for nosocomial infection control, and to help the standardization of PICC care program.Methods:1 Research objectsAnalyzing studies were performed on a group of ICU patients of our hospital between January 2011 and December 2014. Patients under the study had fever, cold shiver and/or low blood pressure, but no obvious origin of infection, local infection of point of puncture, or suppurative infection. We selected 423 cases of possible infection from peripherally inserted central catheter and performed blood culture and catheter-tip culture.2 Catheter-tip culture(semi-quantitative culture)5 cm of catheter-tip were inoculate onto Columbia blood agar, Mac Conkey Agar, and nutrient broth(culture enrichment), Roll the agar surface back and force once, culture 24 hours. It is considered positive when bacterium count is larger or equal to 15 CFU/agar.3 Blood cultureCentral venous catheter culture and bacterium infusion to PICC-drawn blood culture were also prepared. The blood culture test results, including bacteria types and antimicrobial resistance test, are consistent to the result above. The bacteria density ratio between the two was larger than 5:1. The time to show positive from central venous catheter culture preparation was at least two hours shorter than that of PICC. When the blood cultivator showed positive, the sample was subcultivted in Columbia agar and Mac Conkey Agar. Evaluation and antimicrobial resistance test were carried out after 24 hours of culture development.4 Identification and antibiotic susceptibility testVITEK2 compact bacteria assay drug sensitive analyzer was used to perform bacterium identification and drug sensitivity test. The bacterial suspension configuration: using pure cultures of fresh detection(Age: 18-24 hours)Suspension,Identification of bacteria in 0.85% Na CL or deionized water modulation corresponding suspension concentration, and the use of DENSITMAT turbidimeter calibration concentration, the concentration of bacterial suspension in 0.5-0.63 Mac.Then on the identification and drug sensitivityResults:1 The composition of pathogenic bacteria Of 423 patients with possible infection from peripherally inserted central catheter, 34( 8.04%) were confirmed to be catheter-related bloodstream infection. 38 were separated. Of 38 pathogenic bacteria, 23( 60.52%) were Gram-positive, included 9 Staphylococcus aureus, 6 staphylococcus haemolyticus, 4 enterococcus faecalis, 2 staphylococcus epidermidis, 1 enterococcus faecium and 1 staphylococcus hominis. Four of the enterococcus faecalis are Methicillin-resistant Staphylococcus aureus(MRSA). Four of the staphylococcus haemolyticus are methicillin-resistant Sraphylococcus coagulase – negative(MRSCON). There were 11(28.95%)Gram-negative: 3 Klebsiella pneumoniae, 3 Escherichia coli, 3 Serratia marcescens, 1 acinetobacter junii, and 1 pseudomonas aeruginosa. One of the Escherichia coli and two of the Klebsiella pneumoniae were Extended-spectrum β-lactamases(ESBL) becateria. There were 4(10.53%)fungi: 2 Candida glabrata, 1 Candida parapsilosis, and 1 Candida albicans.2 From 2011 to 2014 the cultivation of isolated pathogenic bacteriainfection of catheter related blood stream of 38 strains 。 Respectively In,in 2011 19 strains isolated rate was 13.1%,In 2012 3 strains isolated rate was 4%,in 2013 8 strains isolated rate was 8.3%,in 2014 8 strains isolated rate was 8.3%. The separation rate into the trend of decreasing year by year.3 The result of antibiotic susceptibility test 23 Gram positive strains were highly sensitive to Vancomycin and teicoplanin. They showed relative high resistivity to penicillin, erythromycin, Clindamycin, cyclomycin and quinolones. 11 Gram-negative syrains were relatively sensitive to Piperacillin/ tazobactam sodium, amikacin, and Carbapenems. Among the separated Candida, candida albicans is relative sensitive to fluconazole, amphotericin-b, 5-Flucytosine, itraconagole, and Voriconazole. Glabrata dose not have positive effect to Fluconazole and Itraconagole.Conclusion:1 Of 423 patients with possible infection from peripherally inserted central catheter, 34( 8.04%) are confirmed to be catheter-related bloodstream infection. The infection rata are higher at the begin usage year of PICC, with 13.10%.2 The Gram-positive bacteria are the major pathogen of catheter-related bloodstream infection, counted 60.52%, followed by Gram-negative bacteria(28.95%) and fungi(10.53%)3 Staphylococci and Enterobacteriaceae are the relatively common pathogen of catheter-related bloodstream infection, with a higher drug resistance rate.4 The standardized operation procedures of PICC techniques and hospital management should be improved and enhanced to reduce infections rate.