Colonisation of the ventilated airway

Inglis, Timothy John Jay (1990) Colonisation of the ventilated airway. University of Southampton, Doctoral Thesis.

Abstract

A prospective study of bacterial colonisation of the lower respiratory tract was conducted in intensive care patients. There was evidence to support the spread of bacteria into the lower respiratory tract from the stomach and oropharynx, and up into the tracheal tube. Prolonged mechanical ventilation and factors contributing to a raised intragastric pH were associated with the presence of Gram negative bacilli in the trachea. A biofilm was found on the inner surface of most adult tracheal tubes, from which particles small enough to penetrate far into the lungs were shown to be scattered during a normal ventilator cycle. This phenomenon was demonstrated with tubes from adult and premature neonatal patients, and in both cases would provide a means of delivering bacteria to the lungs. It is concluded that particle scatter resulting from gas-liquid interaction in trachael tubes containing a biofilm, might contribute to the development of ventilator-associated pneumonia in adults, and bronchopulmonary dysplasia in premature neonates. The implications for preventive strategies are considered.

This record has no associated files available for download.

Contributors

Download statistics