title: The relationship between intravenous infusate colonisation and fluid container hang time.
abstract: OBJECTIVE
  To examine the level of microbial colonisation in intravenous fluids after 24 hours of use in an acute care setting to determine the necessity of changing infusate bags on a time-related basis.
  
  
  BACKGROUND
  Catheter-related bloodstream infections are a serious and life-threatening complication of intravascular devices. Colonised intravenous fluids are one potential source of infection; however, there is little published literature on incidence rates and few recent studies. Routine intravenous fluid replacement has been advocated as an infection control method, but the effectiveness of this is unknown and the optimal duration for infusate use remains uncertain.
  
  
  METHODS
  Cross-sectional study over 18 months in a 257-bed teaching hospital.
  
  
  METHODS
  Infusate specimens (n = 264) were obtained from crystalloid fluids that had been used for 24 hours or more. Microbiological culture and sensitivity testing was performed and infusate-related bloodstream infection (IRBSI) rates were recorded. Sample testing of previously unopened intravenous solutions acted as a control.
  
  
  RESULTS
  The infusate colonisation rate was 0.4%, or 0.09 per 1000 infusion hours. The only isolated organism was coagulase-negative Staphylococcus. Infusions had been in use for 24-185 hours (1-8 days). There was no difference in median duration of use for colonised (35.0 hours) and sterile (34.0 hours) specimens (Mann-Whitney test, p = 0.99). There were no cases of IRBSI.
  
  
  CONCLUSIONS
  The incidence of intravenous fluid colonisation and the risk of related bloodstream infection are low even after several days of infusate use. Current practice appears to successfully maintain the sterility of intravenous fluids.
  
  
  CONCLUSIONS
  Routine replacement of intravenous fluids continues in many settings, often 24 hourly, in the belief that this prevents infection. We found no relationship between duration of use and colonisation and routine replacement may be unnecessary. Further research is needed to investigate the effectiveness of routinely replacing intravenous fluids at set time points to prevent colonisation and infection.
authors.affiliation: Research Centre for Clinical and Community Practice Innovation, Griffith University, Nathan, Qld, Australia. c.rickard@griffith.edu.au
authors.forename: Claire M
authors.initials: CM
authors.lastname: Rickard
authors.forename: Boun
authors.initials: B
authors.lastname: Vannapraseuth
authors.forename: Matthew R
authors.initials: MR
authors.lastname: McGrail
authors.forename: Lorraine J
authors.initials: LJ
authors.lastname: Keene
authors.forename: Sam
authors.initials: S
authors.lastname: Rambaldo
authors.forename: Chloe A
authors.initials: CA
authors.lastname: Smith
authors.forename: Gillian
authors.initials: G
authors.lastname: Ray-Barruel
mesh_terms: D003430:Cross-Sectional Studies; D005440:Fluid Therapy; D006784:Hospitals, Teaching; D006801:Humans; D017053:Infection Control; D007262:Infusions, Intravenous; D009729:Nursing