Effectiveness of oral rinse with chlorhexidine in preventing nosocomial respiratory tract infections among intensive care unit patients

Infect Control Hosp Epidemiol. 2009 Oct;30(10):952-8. doi: 10.1086/605722.


Objective: To evaluate the effectiveness of the oral application of a 0.12% solution of chlorhexidine for prevention of respiratory tract infections among intensive care unit (ICU) patients.

Design: The study design was a double-blind, randomized, placebo-controlled trial.

Setting: The study was performed in an ICU in a tertiary care hospital at a public university. PATIENTS. Study participants comprised 194 patients admitted to the ICU with a prospective length of stay greater than 48 hours, randomized into 2 groups: those who received chlorhexidine (n = 98) and those who received a placebo (n = 96).

Intervention: Oral rinses with chlorhexidine or a placebo were performed 3 times a day throughout the duration of the patient's stay in the ICU. Clinical data were collected prospectively.

Results: Both groups displayed similar baseline clinical features. The overall incidence of respiratory tract infections (RR, 1.0 [95% confidence interval [CI], 0.63-1.60]) and the rates of ventilator-associated pneumonia per 1,000 ventilator-days were similar in both experimental and control groups (22.6 vs 22.3; P = .95). Respiratory tract infection-free survival time (7.8 vs 6.9 days; P = .61), duration of mechanical ventilation (11.1 vs 11.0 days; P = .61), and length of stay (9.7 vs 10.4 days; P = .67) did not differ between the chlorhexidine and placebo groups. However, patients in the chlorhexidine group exhibited a larger interval between ICU admission and onset of the first respiratory tract infection (11.3 vs 7.6 days; P = .05). The chances of surviving the ICU stay were similar (RR, 1.08 [95% CI, 0.72-1.63]).

Conclusion: Oral application of a 0.12% solution of chlorhexidine does not prevent respiratory tract infections among ICU patients, although it may retard their onset.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Administration, Oral
  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Anti-Infective Agents, Local / administration & dosage*
  • Chlorhexidine / administration & dosage*
  • Cross Infection* / epidemiology
  • Cross Infection* / etiology
  • Cross Infection* / prevention & control
  • Double-Blind Method
  • Female
  • Humans
  • Incidence
  • Intensive Care Units
  • Length of Stay
  • Male
  • Middle Aged
  • Oropharynx / microbiology
  • Respiratory Tract Infections* / epidemiology
  • Respiratory Tract Infections* / etiology
  • Respiratory Tract Infections* / prevention & control
  • Treatment Outcome
  • Young Adult


  • Anti-Infective Agents, Local
  • Chlorhexidine