How do endotracheal tubes increase the risk of infection?

a. By increasing bleeding risks
b. Providing surfaces for biofilms to develop
c. By reducing neutrophil effectiveness
d. By increasing mucociliary escalator clear-ance

ANS: B
Endotracheal tubes allow pathogens to increase the risk of infection by impeding local host de-fenses and providing biofilms that may facilitate adherence of pathogens.