Which of the following statements is false regarding the use of an inspiratory pause during me-chanical ventilation?

a. It may be useful in ARDS patients.
b. It may be useful when obtaining a chest radiograph.
c. It has been shown to increase effective-ness of bronchodilator therapy.
d. It will increase mean airway pressure.

ANS: C
The use of a single long inspiratory pause (up to 40 sec) has been advocated in the management of acute lung injury/ARDS as a lung recruitment maneuver, and the results have been encourag-ing. Use of an inspiratory pause has been suggested for administration of bronchodilators to im-prove medication delivery. In the treatment of chronic obstructive pulmonary disease patients, however, a 5-sec inspiratory pause did not result in significant improvement in measures related to the effectiveness of the bronchodilator. If a brief inspiratory pause is used, 1:E ratio and mean airway pressure increase. An inspiratory pause of 0.5 to 1.0 sec applied for a single breath is used for measurement of plateau pressure (Pplat) and in estimation of airway resistance (Raw) where PIP is peak inspiratory pressure and is inspiratory peak flow (square wave). An inspiratory pause can also be used to ensure a full inspiration before a chest radiograph is obtained, and this step may improve the quality of the resulting radiograph.