title: Mechanical ventilation with or without 7-day circuit changes. A randomized controlled trial.
abstract: OBJECTIVE
  To determine whether a practice of not routinely changing ventilator circuits in patients who require prolonged mechanical ventilation is associated with an increased incidence of nosocomial pneumonia.
  
  
  METHODS
  Randomized controlled trial.
  
  
  METHODS
  Intensive care units in two university-affiliated teaching hospitals.
  
  
  METHODS
  300 patients admitted to an intensive care unit who required mechanical ventilation for more than 5 days.
  
  
  METHODS
  Patients were randomly assigned to receive either no routine ventilator circuit changes or circuit changes every 7 days.
  
  
  METHODS
  The primary outcome measure was the incidence of ventilator-associated pneumonia. Other outcome measures included duration of mechanical ventilation, length of hospital stay, and hospital mortality.
  
  
  RESULTS
  147 patients were randomly assigned to receive no routine ventilator circuit changes, and 153 patients were randomly assigned to receive circuit changes every 7 days. The two groups were similar at the time of randomization with regard to demographic characteristics, intensive care unit admission diagnoses, and severity of illness. Ventilator-associated pneumonia was seen in 36 patients (24.5%) receiving no routine changes and in 44 patients (28.8%) receiving changes every 7 days (relative risk, 0.85 [95% CI, 0.55 to 1.17]). No statistically significant differences for hospital mortality, intensive care unit mortality, death during mechanical ventilation, death in patients with ventilator-associated pneumonia, or mortality directly attributed to ventilator-associated pneumonia were found between the two treatment groups (P > or = 0.11). Patients receiving changes every 7 days had 247 circuit changes costing a total of $7410; patients receiving no routine changes had a total of 11 circuit changes costing $330.
  
  
  CONCLUSIONS
  The elimination of routine ventilator circuit changes can reduce medical care costs without increasing the incidence of nosocomial pneumonia in patients who require prolonged mechanical ventilation.
authors.affiliation: Pulmonary and Critical Care Division, Washington University School of Medicine, St. Louis, MO 63110, USA.
authors.forename: M H
authors.initials: MH
authors.lastname: Kollef
authors.forename: S D
authors.initials: SD
authors.lastname: Shapiro
authors.forename: V J
authors.initials: VJ
authors.lastname: Fraser
authors.forename: P
authors.initials: P
authors.lastname: Silver
authors.forename: D M
authors.initials: DM
authors.lastname: Murphy
authors.forename: E
authors.initials: E
authors.lastname: Trovillion
authors.forename: M L
authors.initials: ML
authors.lastname: Hearns
authors.forename: R D
authors.initials: RD
authors.lastname: Richards
authors.forename: L
authors.initials: L
authors.lastname: Cracchilo
authors.forename: L
authors.initials: L
authors.lastname: Hossin
mesh_terms: D000328:Adult; D000368:Aged; D003428:Cross Infection / Q000209:etiology / Q000401:mortality / Q000517:prevention & control*; D005260:Female; D017052:Hospital Mortality; D006785:Hospitals, University; D006801:Humans; D015994:Incidence; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011014:Pneumonia / Q000209:etiology / Q000401:mortality / Q000517:prevention & control*; D012121:Respiration, Artificial / Q000009:adverse effects / Q000191:economics / Q000295:instrumentation* / Q000401:mortality; D013997:Time Factors