Table 2. Etiology of 40 episodes of ventilator-associated tracheobronchitis.

Agents	Infections (%)
Pseudomonas aeruginosa	31.0
Klebsiella pneumoniae	19.0
Serratia marcescens	7.0
Staphylococcus aureus	7.0
Enterococcus faecalis	4.80
Enterobacter aerogenes	4.80
Acinetobacter baumannii	4.80
Stenotrophomonas maltophilia	4.80
Elizabethkingia meningoseptica	4.80
Achromobacter xylosoxidans	2.4
Citrobacter koseri	2.4
Providencia stuartii	2.4
Burkholderia pickettii	2.4
Acinetobacter lwoffii	2.4
Total	100