Risk Factors For And Influence Of Bloodstream Infection On Mortality In The Intensive Care Unit:a3-year Prospective Study

Objective: To evaluate the clinical, microbial and prognostic characteristics ofbloodstream infection happened from2010to2012in the ICU of General Hospital ofNingxia Medical University, we conducted a retrospective study, trying to direct thescreening on high-risk patients, the use of empiric antibiotic therapy and the prognosticassessment.Methods: An observational, retrospective analysis was taken by collecting the data ofthe patients who had taken blood culture specimens, including clinical data, microbial dataand prognostic data, which were collecting by standard chart that designed previously. SPSSsoftware was used in the data analysis.Results: We identified a total of910ICU admissions who get the blood culturespecimens,whose119patients diagnosed as bloodstream infections. The positive rate was13.07%. The total mortality rate was27.6%while the patients with bloodstream infectionscrude mortality rate was54.6%. The proportion of male: female=3.69:1. The age of themare (52±18) years old (rang,14-90years).359patients are older than60years old,accounting for39.5%. Under the same baseline characteristics of patients included, thepredictive factors for the occurrence of bloodstream infections are diabetes, chronic kidneydisease, chronic liver disease, central venous puncture, mechanical ventilation and surgery.55.5%of the patients (66patients) who definitely diagnose as bloodstream infection arediagnosed in the first24hours of ICU，most commonly transferred from he emergencydepartment, followed by gastrointestinal surgery and neurosurgery.53patients (44.5%) areafter the first24hours. The rate of Methicillin-resistant Staphylococcus aureus (MRS) is high. In the detection of Staphylococcus, the rate of coagulase-negative staphylococci (CNS) arehigher than Staphylococcus aureus (SAU). The resistance rates of oxacillin, penicillin G,erythromycin are high, but no vancomycin-resistant strains are found. The secondarycommon Gram-positive bacteria are enterococcus bacteria, whose resistance rates are high.Of Gram-negative bacilli, Acinetobacter baumannii and Escherichia coli are most common.Acinetobacter baumannii imipenem resistance rate reached71.43%. The resistance rate toother antibiotics except amikacin is greater than80%, while the resistance rate to amikacinalso reached21.43%. Of the patients with bloodstream infections(119patients),65caseswere dead. Advanced age, GCS <8, combined with respiratory failure, with tumor wereindependent risk factors of death in patients with bloodstream infections, and after surgerywas negatively correlated with the patients’death.Conclusions: The incidence and mortality of bloodstream infection in ICU are high.Underlying diseases and invasive procedures are major risk factors for occurrence ofbloodstream infections. Emphasis should be place on that who has the risk factors. Positivebacterial infections are more common, but the resistance of negative ones is higher, and theprognosis is worse. Therefore, Gram-negative bacilli resistant control is a major factor toimprove the prognosis of patients with bloodstream infections in ICU. For patients withbloodstream infections, invasive operation and antibiotic treatment do not affect theprognosis of patients, but advanced age and the combination of organ dysfunctionsignificantly affect the patient’s mortality.