Dislodgement of bacteria from endotracheal tubes after saline instillation and suction catheter insertion

Abstract

Bacterial glycocalyx formations on the inner lumens of endotracheal tubes may be dislodged into the lower airway by suction catheter insertions or saline instillations. Repeated introduction of bacteria into the lower airway may overwhelm host defense mechanisms, leading to nosocomial pneumonia. Ten crossover subjects required intubation for 2 to 39 days. A range of 0-62,000 (mean 26,980) viable bacterial colonies per milliliter was dislodged from freshly removed endotracheal tubes by either catheter insertion or saline instillation. There was no significant difference in numbers of viable bacteria dislodged from endotracheal tubes by catheter insertion versus a 5 milliliter saline instillation. The large numbers of coated bacteria dislodged could be an underestimated infectious hazard, particularly as endotracheal suctioning is generally performed multiple times each day for intubated patients. As optional saline instillations have not improved endotracheal suctioning outcomes in previous studies, caregivers should consider deleting saline instillation during endotracheal suctioning.