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CARDIOVASCULAR PHYSIOLOGY CONCEPTS
4.
A sudden increase in carotid artery
pressure
a. Decreases carotid sinus baroreceptor
firing rate.
b. Increases sympathetic efferent nerve
activity to systemic circulation.
c. Increases vagal efferent activity to the
heart.
d. Results in reflex tachycardia.
5.
Which of the following can cause
tachycardia?
a. Increased arterial pulse pressure
b. Increased blood PCO2
c. Increased firing of carotid sinus
baroreceptors
d. Vasovagal reflex
6.
Infusion of a high dose of epinephrine
following pharmacologic blockade of
P-adrenoceptors will
a. Decrease mean arterial pressure.
b. Have no significant cardiovascular
effects.
c. Increase heart rate.
d. Increase systemic vascular
resistance.
7.
In an experimental protocol, intravenous
infusion of acetylcholine was found
to decrease mean arterial pressure and
increase heart rate. These results can
best be explained by
a. Direct action of acetylcholine on
muscarinic receptors at the sinoatrial
node.
b. Increased firing of carotid sinus baro-
receptors.
c. Reflex activation of sympathetic
nerves.
d. Reflex systemic vasodilation.
8.
A 27-year-old female patient with severe
hypertension is found to have bilateral
renal artery stenosis caused by fibro-
muscular dysplasia of the renal arteries
resulting in elevated levels of circulating
renin. One mechanism contributing to
her hypertension is
a. Increased blood volume.
b. Increased circulating atrial natriuretic
peptide.
c. Increased sodium loss by the kidneys.
d. Inhibition of aldosterone release.
9.
A hospitalized patient with acute decom-
pensated heart failure is given a drug
that increases circulating atrial natriu-
retic peptide by inhibiting its metabo-
lism. What beneficial effects would this
treatment have in this patient?
a. Decrease blood volume by promoting
sodium loss by the kidneys
b. Increase blood pressure by constricting
the arterial and venous vasculature
c. Increase cardiac output by increasing
preload
d. Stimulate the release of aldosterone
from the adrenal cortex
10. Following an automobile accident that
resulted in significant hemorrhage, a
48-year-old male patient is admitted to the
Emergency Department in critical condition
with an arterial pressure of 65/45 mm Hg
and a heart rate of 140 beats/min. Fluid
resuscitation was augmented by administra-
tion of arginine vasopressin. The potential
benefit of adding vasopressin during resus-
citation is derived from its ability to
a. Augment sympathetic activity.
b. Increase systemic vascular resistance.
c. Produce renal fluid loss (diuresis).
d. Stimulate the release of renin.
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