Question 1

A patient is wheezing and short of breath. The nurse assesses a heart rate of 88 beats/min, a respiratory rate of 24 breaths per minute, and a blood pressure of 124/78 mm Hg. The prescriber orders a nonspecific beta agonist medication. Besides evaluating the patient for a reduction in respiratory distress, the nurse will monitor for which side effect?

A) Hypotension
B) Tachycardia
C) Tachypnea
D) Urinary retention

Tachycardia

Accepted Answer

Beta agonists are used for asthma because of their beta₂ effects on bronchial smooth muscle, causing dilation. Beta₁ effects cause tachycardia and hypertension. Beta receptors do not exert effects on the bladder.

Question 2

A pregnant patient is in premature labor. Which class of drug will she be given? A) Alpha₁ agonist B) Anticholinergic C) Beta₂ agonist D) Beta₂ antagonist

Accepted Answer

Beta₂ agonists cause relaxation of uterine muscle, slowing or stopping the contractions that precipitate labor. An alpha₁ agonist would have effects on the heart and arterioles. Anticholinergic drugs generally are given for their effects on the urinary and GI tracts and do not affect uterine muscle. A beta₂ antagonist would cause increased constriction of uterine muscle.

Question 3

A nurse is teaching a patient about a medication that alters sympathetic nervous system functions. To evaluate understanding, the nurse asks the patient to describe which functions the sympathetic nervous system regulates. Which answer indicates the need for further teaching?

A) "The digestive functions of the body"
B) "The cardiovascular system"
C) "The 'fight-or-flight' response"
D) "Body temperature"

"The digestive functions of the body"

Accepted Answer

The sympathetic nervous system does not regulate digestive functions of the body-the parasympathetic nervous system does; further education is needed. The sympathetic nervous system regulates the cardiovascular system, the fight-or-flight response, and the body temperature; no further education is needed.

Question 4

A nurse is administering an agonist drug that acts on postganglionic neurons of the sympathetic nervous system. Which response will the nurse expect to see?&#10;A) Decreased sweating&#10;B) Bronchodilation&#10;C) Increased cardiac output&#10;D) Pinpoint pupils

Accepted Answer

Norepinephrine (NE) is the most common neurotransmitter released by all postganglionic neurons of the sympathetic nervous system except those going to sweat glands where ACh is the neurotransmitter. NE acts on alpha₁, alpha₂, and beta₁ receptors to increase the force and rate of cardiac contraction, thus increasing cardiac output. ACh would increase sweating. Bronchodilation occurs when epinephrine activates beta₂ receptors on bronchial smooth muscle. NE affects alpha₁ receptors to dilate the pupils.

Question 5

A patient is to receive a beta agonist. Before administration of this medication, which assessment finding would most concern the nurse?&#10;A) Pulse oximetry reading of 88%&#10;B) Blood pressure of 100/60 mm Hg&#10;C) Respiratory rate of 28 breaths per minute&#10;D) Heart rate of 110 beats/min

Accepted Answer

A beta agonist dilates respiratory smooth muscle, but as a side effect, it can stimulate the heart. A heart rate of 110 beats/min is a concern, because this medication may further increase the already elevated heart rate. A pulse oximetry reading of 88% is a concern, but the medication causes bronchodilation and increased oxygenation; this should increase the pulse oximetry reading. A blood pressure of 100/60 mm Hg is on the low side, but this medication may actually cause an increase in blood pressure as a side effect; this should not concern the nurse before administration of the medication. A respiratory rate of 28 breaths per minute is elevated; however, this medication should increase oxygenation by bronchodilation, and the patient's respiratory rate should decrease once oxygenation has improved. Therefore, this should not concern the nurse.

Question 6

What is the target organ when a beta₁ agonist is administered? A) Heart B) Kidney C) Respiratory D) Liver

Accepted Answer

A beta₁ agonist increases the patient's heart rate and blood pressure and is used in heart failure. Beta₁ agonists would not be used for kidney, respiratory, or liver failure.

Question 7

A nurse is explaining activation of beta₂ receptors to nursing students during a clinical rotation at the hospital. Which statement by a student demonstrates a need for further teaching? A) "Beta₂ activation results in bronchodilation." B) "Beta₂ activation results in contraction of uterine muscle." C) "Beta₂ activation results in glycogenolysis." D) "Beta₂ activation results in vasodilation of skeletal muscles."

Accepted Answer

Beta₂ activation would result in relaxation of uterine smooth muscle, not contraction; this statement indicates a need for further teaching. Bronchodilation is an effect of beta₂ activation; no further teaching is needed. Beta₂ activation does result in glycogenolysis; no further teaching is needed. Beta₂ activation does result in vasodilation of skeletal muscle; no further teaching is needed.

Question 8

Many medications list side effects that include dry mouth, constipation, and urinary retention. What kinds of effects are these?&#10;A) Alpha adrenergic&#10;B) Anticholinergic&#10;C) Beta adrenergic&#10;D) Sympathetic

Accepted Answer

Cholinergic stimulation by ACh causes increased salivation, increased gastrointestinal (GI) motility, and relaxation of the bladder trigone and sphincter. Anticholinergic medications inhibit these responses, causing dry mouth, constipation, and urinary retention. Alpha-adrenergic agents effect processes in the sympathetic nervous system, causing peripheral vasoconstriction and pupil dilation, among other effects. The effects of beta-adrenergic medications are seen mostly in the heart and blood vessels. The sympathetic nervous system has both cholinergic and adrenergic transmitters.

Question 9

A nurse is teaching a group of nursing students about neurotransmitters. Which statement by a student about acetylcholine indicates a need for further teaching?&#10;A) &#34;It activates three cholinergic receptor subtypes.&#34;&#10;B) &#34;It has effects in the parasympathetic, sympathetic, and somatic nervous systems.&#34;&#10;C) &#34;It is used at most junctions of the peripheral nervous system.&#34;&#10;D) &#34;Its transmission is terminated by reuptake into the cholinergic nerve terminal.&#34;

Accepted Answer

Acetylcholine (ACh) is destroyed by acetylcholinesterase, an enzyme that degrades ACh into two inactive products: acetate and choline. Choline is taken up into the nerve terminal. ACh activates three receptor sites: nicotinicN, nicotinicM, and muscarinic. ACh has effects throughout the peripheral nervous system (PNS) and is used at most junctions in the PNS.

Deck 13: Physiology of the Peripheral Nervous System