A mechanically ventilated patient has developed VAP from an ...

[Jkov05]

A mechanically ventilated patient has developed VAP from an endogenous source. How could such bacteria have invaded this patient's lungs? I. growth from condensate in the ventilator breathing circuit II. an HME not changed in a timely fashion III. gastroesophageal reflux IV. colonization of bacteria on the patient's skin
 
  A. I, II only
  B. III, IV only
  C. I, II, IV only
  D. II, III, IV only

Question 2

Why are the use of antacids or histamine H2 receptor antagonists risk factors for the development of VAP?
 
  A. These medications cause biofilm to accumulate within the endotracheal tube.
  B. These drugs cause resident bacteria to overcolonize in the small intestine and invade the stomach.
  C. These drugs cause the overgrowth of gram-positive bacteria in the oropharynx.
  D. These medications increase gastric pH and can cause bacterial gastric colonization.

[billybob123]

Answer to Question 1

ANS: B
A. Incorrect response: See explanation B.
B. Correct response: Colonization of the oropharynx and trachea with the causative pathogen has been shown to be important in the pathogenesis of VAP. Endogenous bacteria (stomach and intestines) can reach the oropharynx after colonizing the skin or via a vector, such as hands of the ICU team, or by gastroesophageal reflux.
C. Incorrect response: See explanation B.
D. Incorrect response: See explanation B

Answer to Question 2

ANS: D
A. Incorrect response: See explanation D.
B. Incorrect response: See explanation D.
C. Incorrect response: See explanation D.
D. Correct response: The stomach is normally sterile because of the low pH. However, colonization within the stomach can occur in critically ill patients because of an increase in the pH of the gastric contents caused by the use of H2 blockers, antacids, and enteral feeding. Any of these factors can increase gastric pH and lead to gastric colonization. Once colonized, the stomach acts as a reservoir from which pathogenic bacteria can colonize the oropharynx and trachea, or get aspirated directly into the lungs.

[Jkov05]

Excellent

[cam1229]

Gracias!