Impact of persistent endotracheal tube biofilm on ventilator-associated pneumonia clinical and microbiological response

Methods All patients over 18 years old admitted to the Intensive Care Unit of the Hospital Universitario and Politecnico la Fe (Valencia, Spain), undergoing mechanical ventilation and with VAP diagnosis were included. Clinical and microbiological data were collected at the moment of inclusion and on days 3 and 7 after VAP diagnosis. After ETT removal, ETT was washed and a piece of 0.5 cm length was cut and sonicated and the resulting material was quantitatively cultured (100 uL blood agar plate with counting of colonies with 100 uL in isolation in chocolate blood agar). Clinical response (resolution of VAP signs: fever, high leucocyte count and respiratory purulence) was evaluated at day 3 and day 7. Median and interquartile range (IR) was calculated for continuous variables, and absolute and relative frequencies for discrete variables. Statistical analysis was done by chisquare test.