Why is the total mechanical work of breathing difficult to assess ...

[saliriagwu]

Why is the total mechanical work of breathing difficult to assess during spontaneous breathing?
 
  a. Most volunteer subjects cannot under-stand the procedure used.
  b. Respiratory muscle activity contributes to inflation resistance.
  c. The respiratory muscles (diaphragm, etc.) must be paralyzed.
  d. The subjects used to make the measure-ments must be unconscious.

Question 2

Which of the following formulas is used to compute the mechanical work of breathing?
 
  a. Change in pressure/flow
  b. Change in pressure  change in flow
  c. Change in pressure  change in volume
  d. Change in volume/change in pressure

[Kdiggy]

Answer to Question 1

ANS: B
The mechanical work of breathing cannot be measured easily during spontaneous breathing. This is because the respiratory muscles contribute to the resistance offered by the chest wall.

Answer to Question 2

ANS: C
The mechanical work of breathing can be calculated as the product of the pressure across the res-piratory system and the resulting change in volume.

[saliriagwu]

Gracias!

[xiaomengxian]

TYSM