Author Question: Which of the following physiologic effects is associated with the Valsalva maneuver? A. increased ... (Read 90 times)

bobypop · **on:** Jul 16, 2018

Which of the following physiologic effects is associated with the Valsalva maneuver?

A. increased right ventricular preload
B. decreased left ventricular afterload
C. increased cardiac output
D. increased venous return

Question 2

How should the therapist instruct a patient to perform a Valsalva maneuver for the assessment of respiratory mechanics?

A. Have the patient pant rapidly just above and below normal tidal breathing for 12 seconds.
B. Instruct the patient to exhale as rapidly and as forcefully as possible against a closed glottis for several seconds.
C. Teach the patient to perform an inspiratory maneuver, similar to sucking on a straw, for several seconds.
D. Coach the patient to breath hold for approximately 10 seconds.

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

Answer to Question 1

ANS: B
A. Incorrect response: Venous return to the right side of the heart decreases. Consequently, right ventricular preload decreases.
B. Correct response: A Valsalva maneuver involves performing an expiratory maneuver against a closed glottis. During a Valsalva maneuver, the pleural pressure increases, and the left ventricular afterload decreases.
C. Incorrect response: Because venous return to the heart decreases during a Valsalva maneuver, the cardiac output decreases.
D. Incorrect response: Because of the high pleural pressure that develops, venous return to the left ventricle decreases when a Valsalva maneuver is performed.

Answer to Question 2

ANS: B
A. Incorrect response: Having the patient pant rapidly just above and below normal tidal breathing for 12 seconds is essentially a maximum voluntary ventilation maneuver.
B. Correct response: A Valsalva maneuver is performed by instructing the patient to make a maximum and forceful expiratory maneuver against a closed glottis for several seconds. This maneuver causes a decreased stroke volume and reduces the cardiac output because it elevates the pleura pressure.
C. Incorrect response: Having the patient pant rapidly just above and below normal tidal breathing for 12 seconds is not used to evaluate breathing mechanics.
D. Incorrect response: Breath holding for 12 seconds is not part of the Valsalva maneuver.