Author Question: An increase in intrinsic work of breathing due to a decrease in static compliance is caused by which ... (Read 51 times)

dalyningkenk · **on:** Jul 16, 2018

An increase in intrinsic work of breathing due to a decrease in static compliance is caused by which of the following?

a. Emphysema
b. Bronchospasm
c. Pulmonary fibrosis
d. Airway inflammation

Question 2

Calculate the airway resistance given the following clinical data: flow rate 60 L/min, PIP 28 cm H2O, Pplateau 21 cm H2O, and PEEP 8 cm H2O.

a. 7 cm H2O/L/sec
b. 13 cm H2O/L/sec
c. 20 cm H2O/L/sec
d. 28 cm H2O/L/sec

jaymee143 · **Reply #1 on:** Jul 16, 2018

Answer to Question 1

ANS: C
Static compliance is influenced by the elastic characteristics of the lungs and thorax. A decrease in static compliance is due to either the lungs becoming stiffer or the thorax's inability to stretch to accommodate volume in the lungs. Pulmonary fibrosis is a pathophysiologic condition that causes the alveoli to become stiffer due to scarring. Therefore, pulmonary fibrosis will increase a patient's work of breathing due to decreases in the static compliance. Emphysema causes an in-crease in static compliance due to the loss of elastic properties of the lungs and also an increase in airway resistance because of bronchospasm, airway inflammation, and airway edema. Bron-chospasm and airway inflammation lead to increased airway resistance and decreased dynamic compliance.

Answer to Question 2

ANS: A
60 L/min = 1 L/sec. Raw = (PIP Pplateau)/(L/sec) = (28 21)/1 = 7 cm H2O/L/sec.