The impact of 0.5% chlorhexidine oral decontamination on the prevalence of colonization and respiratory tract infection in mechanically ventilated patients. Preliminary study.

AIMS

To determine the effect of Chlorhexidine (CHX) 0.5% oral decontamination on the incidence of colonization/infection of lower respiratory tract in critically ill mechanically ventilated patients.

METHODS

The study was conducted in the multidisciplinary ICU. 30 patients, mechanically ventilated for at least 48 hours, were included. The oral care was performed every 6 hours (6 h CHX group) or 12 hours (12 h CHX group). Tracheal samples were collected every day and the mucosal plaque score (MPS) was also assessed.

RESULTS

The MPS score averages were between 3.8 and 6 in the 6 hours CHX group and between 3.6 and 5 in the 12 hours CHX group. There was no positive association between MPS score and frequency of CHX decontamination (p= 0.898). For 60% of patients in 6 h CHX group and for 40% of patients in 12 h CHX group, colonization did not develop until leaving the study. No significant difference were found between groups with respect to frequency of colonization based on its time of onset (p= 0.523). There is a relationship between the isolation of MRSA and CHX oral decontamination at 12 hours (<phi c =0.392, p=0.032).

CONCLUSIONS

In our preliminary study, no signifficant differences were found between 6 or 12 hour CHX oral decontamination with respect to MPS score and colonization. However, MRSA is vulnerable to 6 hours CHX decontamination. Larger sample size studies are required to determine the efficacy of CHX in the prevention of colonization or respiratory tract infections in mechanically ventilated patients.