Objective:To investigate the distribution and the antibiotic resistant of bacteria separated from clinical samples in a tertiary children’s hospital pediatric intensive care unit(PICU) and to provide a rational use of antibiotics.Methods:974 specimens

collected from the PICU were cultured from Jan 1st 2002 to Dec 31st 2005.The isolated bacterial strains were identified and the antibiotic susceptibility was tested with MicroScan-WalkAway 40.Results:378 strains were isolated from 974 specimens

with a bacteria positive rate of 38.8%.Of the 378 strains isolated

288(76.2%) were Gram-negative bacilli

Gram-positive cocci 64(16.4%) and fungi 28(7.4%).The most common gram-negative bacilli were pseudomonas aeruginosa

Escherichia coli and Klebsiella pneumonia.The common gram-positive cocci were S.aureus and S.epidermidis.Pseudomonas aeruginosa were resistant to most antibiotics

with a resistant rate of more than 35%

except relative sensitive to ciprofloxacin

imipenem and cefepime.The resistant rate of Escherichia coli and Klebsiella pneumonia to penicillins and cephalosporins were more than 60%

but all Escherichia coli and Klebsiella pneumonia were sensitive to imipenem.The resistant rate of the gram-positive cocci to penicillin

ampicillin and erythromycin were 100%

100% and more than 75%

respectively.No gram-positive coccus resistant to vancomycin were found.Conclusion:Present situation of bacterial resistance is a serious problem in PICU.Constant surveilliances of bacterial distribution and resistant to antibiotics should be conducted in order to guide rational use of antibiotics.