What appears to be the major cause of lower respiratory tract ...

[penza]

What appears to be the major cause of lower respiratory tract infections for patients receiving mechanical ventilation?
 
  A. premorbid lifestyle
  B. difficult intubation
  C. aspiration
  D. airflow obstruction

Question 2

A patient who has been receiving mechanical ventilation for a week has just developed VAP. How does this epidemiologic variable (time of onset) affect patient treatment and outcome?
 
  A. no different than if the patient developed VAP after 2 days of mechanical ventilation
  B. involvement of multidrug resistant pathogens and increased mortality
  C. associated with antibiotic-sensitive bacteria, but increased mortality
  D. connected with variably sensitive bacteria and better prognosis

[rachel]

Answer to Question 1

ANS: C
A. Incorrect response: See explanation C.
B. Incorrect response: See explanation C.
C. Correct response: For lower respiratory tract infections to occur, the balance between host defenses and microbial propensity for invasion must be shifted in favor of developing pneumonia. The majority of these infections appear to result in aspiration of potential pathogens that have colonized the oropharyngeal airways. Once an adequate concentration of pathogens is present in distal lung tissue and is able to overcome host defenses, pneumonia develops.
D. Incorrect response: See explanation C.

Answer to Question 2

ANS: B
A. Incorrect response: See explanation B.
B. Correct response: The time of onset is an important epidemiologic variable and risk factor for specific pathogens in patients with VAP. Early-onset VAP, onset within the first 4 days of hospitalization, usually carries a better prognosis and is more likely to be caused by antibiotic-sensitive bacteria. Late-onset VAP, after 4 days of hospitalization, is more likely to be caused by multidrug resistant pathogens, and is associated with increased mortality and morbidity.
C. Incorrect response: See explanation B.
D. Incorrect response: See explanation B