[Prevention of nosocomial infections after cardiac surgery by decontamination of the nasopharynx and oropharynx with chlorhexidine; a prospective, randomised study]

Abstract

Objective: To determine the efficacy ofperioperative decontamination of the nasopharynx and oropharynx in reducing nosocomial infection after cardiac surgery with the use of 0.12% chlorhexidine.

Design: Randomized, double-blind, placebo-controlled clinical trial (www.clinicaltrials.gov; identifier NCT00272675).

Methods: The trial was conducted at the Onze Lieve Vrouwe Gasthuis, Amsterdam, the Netherlands, from 1 August 2003-31 August 2005. Of 991 patients older than 18 years who underwent elective cardiothoracic surgery during the study interval, 954 were eligible for the study. They were given an oropharyngeal rinse and nasal ointment was applied which contained either chlorhexidine or placebo. Clinical outcomes were incidence of nosocomial infection, rate of Staphylococcus aureus nasal carriage and duration of hospital stay.

Results: The incidence ofnosocomial infection in the chlorhexidine and placebo groups was 19.8% and 26.2% respectively (absolute risk reduction (ARR): 6.4%; 95% CI: 1.1-11.7; p = 0.002). In particular, lower respiratory tract infections and deep surgical site infections were less common in the chlorhexidine group than in the placebo group (ARR: 6.5%; 95% CI: 2.3-10.7; p = 0.002 and 3.2%; 95% CI: 0.9-5.5; p = 0.002, respectively). For the prevention of one nosocomial infection, 16 patients needed to be treated with chlorhexidine. A significant reduction in S. aureus nasal carriage was found in the chlorhexidine group (57.5%) as compared with a reduction of 18.1% in the placebo group (p < 0.0001). Total hospital stay for patients treated with chlorhexidine was 9.5 days compared with 10.3 days in the placebo group (95% CI: 0.24-1.88; p = 0.04).

Conclusion: Decontamination of the nasopharynx and oropharynx with chlorhexidine appeared to be an effective method to reduce nosocomial infection after cardiac surgery.