title: Effect of open and closed endotracheal suctioning on cross-transmission with Gram-negative bacteria: a prospective crossover study.
abstract: OBJECTIVE
  Cross-transmission of Gram-negative bacteria increases the likelihood of acquisition of infections and emergence of antibiotic resistance in intensive care units. Respiratory tracts of mechanically ventilated patients are frequently colonized with Gram-negative bacteria and endotracheal suctioning may facilitate cross-transmission. It is unknown whether closed suction systems, as compared with open suction systems, prevent cross-transmission. The objective was to determine whether closed suction systems, as compared with open suction systems, reduce the incidence of cross-transmission of Gram-negative bacteria in intensive care units.
  
  
  METHODS
  We performed a prospective crossover study in which both systems were tested unitwide in four intensive care units.
  
  
  METHODS
  Two intensive care units from a university hospital and two from a teaching hospital participated in the trial between January 2007 and February 2008.
  
  
  METHODS
  All patients admitted to the intensive care unit for >24 hrs were included.
  
  
  METHODS
  Closed suction systems and open suction systems were used for all patients requiring mechanical ventilation during 6-month clusters with the order of systems randomized per intensive care unit.
  
  
  RESULTS
  Acquisition and cross-transmission rates of selected Gram-negative bacteria were determined through extensive microbiological surveillance and genotyping. Among 1,110 patients (585 with closed suction systems and 525 with open suction systems), acquisition for selected Gram-negative bacteria was 35.5 and 32.5 per 1,000 patient-days at risk during closed suction period and open suction period, respectively (adjusted hazard ratio, 1.14; 95% confidence interval, 0.9-1.4). During closed suction period, adjusted hazard ratios for acquisition were 0.66 (95% confidence interval, 0.45-0.97) for Pseudomonas aeruginosa and 2.03 (95% confidence interval, 1.15-3.57) for Acinetobacter species; acquisition rates of other pathogens did not differ significantly. Adjusted hazard ratios for cross-transmission during closed suction period 0.9 (0.4-1.9) for P. aeruginosa, 6.7 (1.5-30.1) for Acinetobacter, and 0.3 (0.03-2.7) for Enterobacter species. Overall cross-transmission rates were 5.9 (closed suction systems) and 4.7 (open suction systems) per 1,000 patient-days at risk.
  
  
  CONCLUSIONS
  Closed suction systems failed to reduce cross-transmission and acquisition rates of the most relevant Gram-negative bacteria in intensive care unit patients.
authors.affiliation: Department of Vital Functions, University Medical Center Utrecht, Utrecht, The Netherlands. i.p.jongerden@umcutrecht.nl
authors.forename: Irene P
authors.initials: IP
authors.lastname: Jongerden
authors.forename: Anton G
authors.initials: AG
authors.lastname: Buiting
authors.forename: Maurine A
authors.initials: MA
authors.lastname: Leverstein-van Hall
authors.forename: Ben
authors.initials: B
authors.lastname: Speelberg
authors.forename: Shimriet
authors.initials: S
authors.lastname: Zeidler
authors.forename: Jozef
authors.initials: J
authors.lastname: Kesecioglu
authors.forename: Marc J
authors.initials: MJ
authors.lastname: Bonten
mesh_terms: D000368:Aged; D003428:Cross Infection / Q000517:prevention & control* / Q000635:transmission*; D018592:Cross-Over Studies; D005260:Female; D016905:Gram-Negative Bacterial Infections / Q000517:prevention & control* / Q000635:transmission*; D006801:Humans; D007442:Intubation, Intratracheal / Q000009:adverse effects / Q000295:instrumentation*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012121:Respiration, Artificial / Q000009:adverse effects / Q000295:instrumentation; D013396:Suction / Q000379:methods*; D014132:Trachea / Q000382:microbiology; D016896:Treatment Outcome