The ventilator that functions most physiologically uses which of ...

[burchfield96]

The ventilator that functions most physiologically uses which of the following?
 
  a. Open loop
  b. Double circuit
  c. Positive pressure
  d. Negative pressure

Question 2

Which of the following statements best defines elastance?
 
  a. Ability of a structure to stretch.
  b. Ability of a structure to return to its natu-ral shape after stretching.
  c. Ability of a structure to stretch and remain in that position.
  d. Ability of a structure to fill and empty during static conditions.

[ky860224]

Answer to Question 1

ANS: D
Air is caused to flow into the lungs with a negative pressure ventilator because the ventilator generates a negative pressure at the body surface that is transmitted to the pleural space and then to the alveoli. The transpulmonary pressure becomes greater because the pleural pressure drops. This closely resembles how a normal spontaneous breath occurs.

Answer to Question 2

ANS: B
The opposite of compliance, elastance is the tendency of a structure to return to its original form after being stretched or acted on by an outside force.