Author Question: What is the desired mass median aerodynamic diameter (MMAD) for the effective inhalation of an ... (Read 32 times)

asd123 · **on:** Jul 16, 2018

What is the desired mass median aerodynamic diameter (MMAD) for the effective inhalation of an aerosolized bronchodilator?

A. less than 1 m
B. 1 m to 3 m
C. 3 m to 5 m
D. greater than 5 m

Question 2

Which of the following factors affects the moisture output of an HME? I. tidal volume II. respiratory rate III. patient temperature IV. inspiratory time

A. I, II only
B. III, IV only
C. I, II, IV only
D. I, II, III, IV

Chelseyj.hasty · **Reply #1 on:** Jul 16, 2018

Answer to Question 1

ANS: C
A. Incorrect response: Particles smaller than 1 m diameter reach deep into the tracheobronchial tree, but are commonly removed during exhalation without producing any effect. Particles this size do not significantly deposit on lung tissue to have any effect.
B. Incorrect response: Medications that are intended for penetration and deposition among the peripheral airways should have an MMAD of 1 m to 3 m diameter. Pentamidine is an example of such a medication.
C. Correct response: Medications that have their effects on the large- to medium-sized airways need to be in the range of 3 m to 5 m diameter. Bronchodilators need to be in this particle size range.
D. Incorrect response: Particles greater than 5 m in diameter would not penetrate significantly into the respiratory tract.

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: As a patient's tidal volume increases, moisture output decreases. The amount of the output decrease depends on the efficiency of the device and its dead space. An increased respiratory rate decreases the moisture output of an HME. Increased temperature increases the moisture output. A decrease in the inspiratory time decreases the moisture output of an HME. Similarly, an increase in the expiratory flow caused by decreased lung compliance decreases the moisture output.