Airway colonisation in long-term mechanically ventilated patients

Objective To evaluate the impact of continuous subglottic suctioning and semi-recumbent body position on bacterial colonisation of the lower respiratory tract.Design A randomised controlled trial.Setting The ten-bed medical ICU of a French university hospital.Patients Critically ill patients expected to require mechanical ventilation for more than 5 days.Interventions Patients were randomly assigned to receive either continuous suctioning of subglottic secretions and semi-recumbent body position or to receive standard care and supine position.Measurements and results Oropharyngeal and tracheal secretions were sampled daily and quantitatively cultured. All included patients were followed up from day 1 (intubation) to day 10, extubation or death. Ninety-seven samples of oropharynx and trachea were analysed (40 for the suctioning group and 57 for the control group). The median bacterial counts in trachea were 6.6 Log₁₀ CFU/ml (interquartile range, IQR, 4.4–8.3) in patients who received continuous suctioning and 5.1 Log₁₀ CFU/ml (IQR 3.6–5.5) in control patients. Most of the patients were colonised in the trachea after 1 day of mechanical ventilation (75% in the suctioning group, 80% in the control group). No significant difference was found in the daily bacterial counts in the oropharynx and in the trachea between the two groups of patients.Conclusion Tracheal colonisation in long-term mechanically ventilated ICU patients was not modified by the use of continuous subglottic suctioning and semi-recumbent body position.