title: Impact of a methicillin-resistant Staphylococcus aureus active surveillance program on contact precaution utilization in a surgical intensive care unit.
abstract: OBJECTIVE
  To determine the impact of an active surveillance for methicillin-resistant Staphylococcus aureus (MRSA) on contact precaution utilization, as measured by additional number of contact precaution days attributable to the active surveillance program.
  
  
  METHODS
  Prospective cohort study.
  
  
  METHODS
  Twenty-four-bed surgical intensive care unit (ICU).
  
  
  METHODS
  All patients admitted to the surgical ICU.
  
  
  METHODS
  Nasal cultures for MRSA were performed at admission to a surgical ICU for 19 months. Patients admitted>48 hrs also received weekly and discharge nasal cultures.
  
  
  RESULTS
  Clinical data, including start date and initial indication for contact precautions, were prospectively collected. Of 1,893 admissions, 253 (13%) were found to be MRSA-positive during their ICU stay. One hundred forty-six (58%) were identified by nasal culture alone. Compared with the first 10 months of study, the prevalence of MRSA on admission to the ICU during the last 9 months of the study period significantly increased (7.2% vs. 11.4%, p<.001). Acquisition of MRSA by noncolonized patients remained constant between the first 10 months and last 9 months of study (7.0 vs. 5.5 cases per 1000 patient days, p=.29). Two hundred fourteen (6%) of 3461 total contact precaution days in the ICU were attributable to MRSA active surveillance. In sensitivity analyses, the implementation of rapid, same-day results for MRSA active surveillance would increase contact precaution days by 15% compared with no surveillance. If the total number of vancomycin-resistant enterococci patients in the ICU were reduced by 50%, the contact precaution days attributable to active surveillance would increase to 9%.
  
  
  CONCLUSIONS
  MRSA active surveillance increased total contact precaution days in this ICU by 6% yet detected 58% of MRSA cases that would have been otherwise missed. Despite an increasing prevalence of MRSA on admission to the ICU, the acquisition rate has remained constant.
authors.affiliation: Division of Infectious Diseases, Department of Surgery, Washington University School of Medicine, St. Louis, and Barnes Jewish Hospital, St. Louis, MO 63110, USA. dwarren@im.wustl.edu
authors.forename: David K
authors.initials: DK
authors.lastname: Warren
authors.forename: Rebecca M
authors.initials: RM
authors.lastname: Guth
authors.forename: Craig M
authors.initials: CM
authors.lastname: Coopersmith
authors.forename: Liana R
authors.initials: LR
authors.lastname: Merz
authors.forename: Jeanne E
authors.initials: JE
authors.lastname: Zack
authors.forename: Victoria J
authors.initials: VJ
authors.lastname: Fraser
mesh_terms: D006801:Humans; D007362:Intensive Care Units / Q000592:standards*; D016106:Methicillin Resistance; D008826:Microbial Sensitivity Tests; D011159:Population Surveillance; D015397:Program Evaluation; D011446:Prospective Studies; D013203:Staphylococcal Infections / Q000517:prevention & control*; D013211:Staphylococcus aureus / Q000187:drug effects*; D013503:Surgery Department, Hospital / Q000592:standards*; D016635:Universal Precautions