Ch. 19 Adrenergic blocking drugs Flashcards
What are the 3 classes of adrenergic blockers
alpha blockers, beta blockers, or alpha-beta blockers
What are the effects of alpha adrenergic blockers?
vasodilation
decreased BP
miosis (pupil constriction)
suppressed ejaculation
Which alpha blockers are used primarily for their vasoconstrictive properties?
ergot alkaloids
“ergo-“ prefix
Which alpha blockers are used as antihypertensives because they cause vasodilation?
drugs with suffix “-zosin”
Most alpha blockers are COMPETITIVE/NONCOMPETITIVE in their actions
competitive i.e. they compete with NEP for binding to the receptor
Explain the difference between competitive and noncompetitive alpha blockers
competitive: higher affinity for the receptor than NEP causes the receptor to be less responsive - reversible
noncompetitive: form a covalent bond with the receptor - irreversible
Which adrenergic blockers are also called oxytocics and why?
Ergot alkaloids - because they cause smooth muscle of uterus to contract and induce local vasoconstriction, which help control postpartum and postabortion bleeding
Which adrenergic blockers are used for treatment of BPH?
“zosin” drugs and tamsulosin
- relax smooth muscle of the prostate and bladder to reduce urinary obstruction
Explain how alpha blockers can prevent/control HTN in patients who have pheochromocytoma
pheochromocytoma is a tumor on the adrenal glands and secrete NEP –> SNS stimulation
the alpha blockers noncompetitively block exocrine glands
Which conditions with increased vasoconstriction can treated by the alpha blocker phentolamine?
Raynaud's disease acrocyanosis frostbite extravasation caused by vasopressors (NEP, EP, DA) because phentolamine causes vasodilation
Which of the following are CI’s for alpha blockers?
peripheral vascular disease liver and kidney disease CAD PUD sepsis
Beta 1 blockers are also called ____________
cardioselective beta blockers
cardioselective beta blockers cause what effects on the heart?
reduces HR
slows AV node conduction
prolongs SA node recovery
decreases myocardial oxygen demand by decreasing myocardial contractility
beta-2 adrenergic blockers cause what effects?
bronchiole constriction
vasoconstriction –> increased PVR –> increased BP
impaired insulin secretion from pancreas –> hyperglycemia
release of fatty acids from adipose tissue –> moderately elevated TG’s and reduced HDL’s
why are some beta blockers considered to have cardioprotective effects
they inhibit stimulation by catecholamines, (which are released during myocardial muscle damage and increase myocardial oxygen demand)
what are the cardiac indications of beta blockers?
angina
post-MI
dysrhythmias
HTN
Why are beta blockers able to easily gain access to the CNS? For what application does it allow?
beta blockers have lipophilicity - attraction to lipid or fat
so can be used to treat migraine headaches
can also topically treat ocular disorders such as glaucoma
CI’s for beta blockers?
cardiogenic shock bradycardia pregnancy severe pulmonary disease Raynaud's disease
When adrenergic blockers are used, __________ pulse rate should be taken for ____________ and the healthcare provider should be contacted if less than ____________.
apical
1 minute
60 beats/minute
With adrenergic blockers, when should the healthcare provider be notified (regarding weight gain)?
increase of 1 kg over 24 hours or 2 kg or more within 1 week
What clinical manifestations may appear if the patient is not weaned off adrenergic blockers slowly?
Chest pain or rebound HTN
What is the management of an overdose of adrenergic-blocking drugs?
patient’s stomach should be emptied
- activated charcoal should be given to bind to the drug and remove it from the stomach and circulation
- sorbitol may be given to speed up elimination
- symptomatic and supportive measures e.g. fluids, volume expanders, vasopressors, anticonvulsants
Which of the following will result when a patient who has experienced infiltration of a peripheral infusion of dopamine is injected with alpha-blocker phentolamine (Rogitine)?
a. local analgesia
b. local hypotension
c. local vasodilation
d. local vasoconstriction
C
Which of the following statements is most correct for a patient taking a beta blocker?
a. postural hypotension is not a problem with this drug
b. the drug may be discontinued without any time restraints
c. weaning off the medication is necessary to prevent rebound hypertension
d. the patient should stop taking the medication at once with a gain of 1-2 kg in a week
C
About which of the following should the nurse provide teaching to a patient who has a new prescription for beta blockers?
a. tachycardia
b. tachypnea
c. bradycardia
d. bradypnea
C
For a patient who has had a recent MI, which of the following drugs may be prescribed for its cardioprotective effects?
a. esmolol
b. prazosin
c. metoprolol
d. phentolamine
C
Which of the following conditions should the nurse assess the patient for before initiating therapy with a nonselective beta blocker?
D
What is the management of an overdose of adrenergic-blocking drugs?
patient’s stomach should be emptied
- activated charcoal should be given to bind to the drug and remove it from the stomach and circulation
- sorbitol may be given to speed up elimination
- symptomatic and supportive measures e.g. fluids, volume expanders, vasopressors, anticonvulsants
Which of the following will result when a patient who has experienced infiltration of a peripheral infusion of dopamine is injected with alpha-blocker phentolamine (Rogitine)?
a. local analgesia
b. local hypotension
c. local vasodilation
d. local vasoconstriction
C
Which of the following statements is most correct for a patient taking a beta blocker?
a. postural hypotension is not a problem with this drug
b. the drug may be discontinued without any time restraints
c. weaning off the medication is necessary to prevent rebound hypertension
d. the patient should stop taking the medication at once with a gain of 1-2 kg in a week
C
About which of the following should the nurse provide teaching to a patient who has a new prescription for beta blockers?
a. tachycardia
b. tachypnea
c. bradycardia
d. bradypnea
C
For a patient who has had a recent MI, which of the following drugs may be prescribed for its cardioprotective effects?
a. esmolol
b. prazosin
c. metoprolol
d. phentolamine
C
Which of the following conditions should the nurse assess the patient for before initiating therapy with a nonselective beta blocker?
a. pancreatitis
b. liver disease
c. HTN
d. chronic bronchitis
D
