Exam II CV Drugs antagonists Flashcards
Mechanism of Action
Binds ___ or ___with alpha receptors
[Alpha-adrenergic Antagonists]
competitively or covalently
MOA:
Prevent the effect of ___ and other ___ ___from interacting with the alpha receptor
[Alpha-adrenergic Antagonists]
catecholamines and other alpha agonists
MOA:
Located in the ___ and ___
[Alpha-adrenergic Antagonists]
heart and peripheral vasculature
Effects
Vaso___
___ ___
Reflex ___
Blocks ___ of insulin secretion
[Alpha-adrenergic Antagonists]
dilation
Orthostatic hypotension
tachycardia
inhibition
Effects
Side effects prevent use as essential ____
If beta blockade is not present, ___cardiac stimulation is allowed.
[Alpha-adrenergic Antagonists]
antihypertensives
maximal
MoA – ___ ___
[Phentolamine (Regitine)]
competitive binding
Nonselective – ___ and ___
[Phentolamine (Regitine)]
alpha1 and alpha2
Effects:
___-α1 blockade and direct action on vascular smooth muscle
[Phentolamine (Regitine)]
Vasodilation
Effects:
Cardiac stimulation (increased HR and CO)-___ and ___(blocks neg. feedback of NE)
Side-effects: dysrhythmias, angina, hyper- ___, abd. pain, ___ due to ___ tone
[Phentolamine (Regitine)]
reflex and α2 blockade
peristalsis, diarrhea, parasympathetic
Uses
Acute HTN emergencies, ___
Accidental infiltration of a ___ (___-___ mg in 10 ml)
[Phentolamine (Regitine)]
pheochromocytoma
sympathomimetic, 5-15 mg
Onset –___minutes
Duration – ___-___minutes
Infusion:
[Phentolamine (Regitine)]
2
10-15
1 – 10 mcg/kg/min
MoA – ___ __binding to α-receptors
Nonselective, ___>___
[Phenoxybenzamine (Dibenzyline)]
irreversible covalent
α1>α2
Effects:
___ – orthostatic hypotension exaggerated with hypovolemia, HTN
[Phenoxybenzamine (Dibenzyline)]
Vasodilation
Effects:
Impairment of ___ ___(lower BP with hypovolemia and vasodilating drugs like volatile agents)
[Phenoxybenzamine (Dibenzyline)]
compensatory vasoconstriction
Effects:
___ CO
[Phenoxybenzamine (Dibenzyline)]
Increased
Effects:
Very little change in ___ ___ flow even with ___ BP
[Phenoxybenzamine (Dibenzyline)]
renal blood, decreased
Effects:
Prevents the inhibition of ___ ___
[Phenoxybenzamine (Dibenzyline)]
insulin secretion
Effects:
Pupil ___
[Phenoxybenzamine (Dibenzyline)]
constriction
Effects:
Chronic use may cause ___
[Phenoxybenzamine (Dibenzyline)]
sedation
Effects:
Nasal ___
[Phenoxybenzamine (Dibenzyline)]
congestion
Uses:
Control BP in ___
[Phenoxybenzamine (Dibenzyline)]
pheochromocytoma
Uses:
In trauma patients, used to ___vasoconstriction (shock), only after ___ ___
[Phenoxybenzamine (Dibenzyline)]
reverse, volume replacement
Uses:
___ syndrome
[Phenoxybenzamine (Dibenzyline)]
Raynaud’s
Onset: up to ___ minutes (IV)
Elimination ½ life: ___hours (duration can last up to 4 days)
[Phenoxybenzamine (Dibenzyline)]
60
24
MoA – ___, ___binding with alpha receptors
[Prazosin (Minipress)]
competitive, reversible
Selective – ___ ___
[Prazosin (Minipress)]
α1 antagonist
Effects:
Vasodilation of both ___ and ___
[Prazosin (Minipress)]
arterioles and veins
Effects:
Less reflex ____(___not blocked)
[Prazosin (Minipress)]
tachycardia, alpha2
Uses:
___tension
Severe___
Onset: within 2 hours
Duration: 10-24 hours
[Prazosin (Minipress)]
Hyper
CHF
Onset: ___ hours
Duration: ___-___ hours
[Prazosin (Minipress)]
within 2
10-24
Another alpha blocker that you may see patients taking is ___(Cardura), which is used to treat both ___ and ___
[Prazosin (Minipress)]
Doxazosin
HTN and benign prostatic hypertension.
Selective - ___ ___
[Doxazosin (Cardura)]
α1 antagonist
Once daily dose
Peak ___ to __ hours
Elimination ½ life ___hours
[Doxazosin (Cardura)]
2 to 3 hours
22
Indications:
Benign prostatic hypertrophy
___tension treatment
[Doxazosin (Cardura)]
Hyper
Mechanism of Action
Competitive binding to ___receptors to block the effect of ___and agonists on the heart and smooth muscles of airways and blood vessels
[Beta-adrenergic Antagonists]
beta, catecholamines
MOA:
Prolonged or chronic use of ___ ___causes up-regulation of ___receptors.
[Beta-adrenergic Antagonists]
beta blockers, beta
Nonselective – block both ___ and ___
___, ___
[Classifications]
β1 and β2
Propranolol, timolol
Cardioselective – block ___
___, ___, ___
[Classifications]
β1
Metoprolol, atenolol, esmolol
Partial antagonist – intrinsic ___effect
___myocardial depression and HR reduction
[Classifications]
sympathomimetic
Less
Pure antagonist – ___ ___ effect
[Classifications]
no sympathomimetic
Selectivity is ___-___.
If a big enough dose of a cardioselective beta-blocker is given, the effect can impact ___receptors also.
[Classifications]
dose-related, beta-2
Β1 blockade - Removes ___ ___ to the heart
[Effects of beta-adrenergic antagonists]
sympathetic stimulation
Negative inotropic effects
___ ___
[Effects of beta-adrenergic antagonists]
Myocardial depression
Negative chronotropic effects
___, ___
[Effects of beta-adrenergic antagonists]
Slows HR, sinus rate
Negative dromotropic effects
___the conduction of impulse through the ___ ___
Slows rate of ___ ___ ___
[Effects of beta-adrenergic antagonists]
Slows, AV node
phase 4 depolarization
Increase in lusitropy
___ ___
[Effects of beta-adrenergic antagonists]
Ventricular relaxation
Decrease in bathmotropy
Reduced ___
[Effects of beta-adrenergic antagonists]
degree of excitability
Β2 blockade:
Vaso____
[Effects of beta-adrenergic antagonists}
constriction
B2 Blockade
Unopposed alpha vasoconstriction can cause ___ ___ ___
(increased serum K*)
decreased LV ejection
B2 Blockade
Broncho___
[Effects of beta-adrenergic antagonists]
constriction
B2 Blockade
___ glycogenolysis, blocks ___ related to hypoglycemia, alters fat metabolism (lipolysis).
Inhibits uptake of K into skeletal muscle cells
[Effects of beta-adrenergic antagonists]
Prevents, tachycardia
B2 Blockade
Inhibits uptake of ___into ___ ___ cells
[Effects of beta-adrenergic antagonists]
K
skeletal muscle
? Additive myocardial depressant effects with ___
___ to continue
___ > isoflurane
[Effects of beta-adrenergic antagonists]
anesthetics
Safe
halothane
CNS – cross ___ ___ ___ - fatigue, lethargy, vivid dreams, memory loss, depression
[Effects of beta-adrenergic antagonists]
blood/brain barrier
Cross placenta – fetal ___cardia, ___tension, ___glycemia
[Effects of beta-adrenergic antagonists]
Brady, hypo, hypo
GI – ___, ___, ___
[Effects of beta-adrenergic antagonists]
nausea, vomiting, diarrhea
Chronic use – fever, rash, ____, alopecia, ____
[Effects of beta-adrenergic antagonists]
myopathy, thrombocytopenia
___ ___block – slowed conduction may be enhanced
[Contraindications to beta-blockade]
AV heart
___ – eliminates tachycardia that is compensating for decrease in volume
[Contraindications to beta-blockade]
Hypovolemia
____ – increased airway resistance (___ or ___)
[Contraindications to beta-blockade]
COPD, nonselective or high doses
Diabetic – mask signs of ___ (nonselective or high doses)
[Contraindications to beta-blockade]
hypoglycemia
Peripheral vascular disease, Raynaud’s syndrome or ____-___ agonist – vasoconstriction unopposed (nonselective), ____ extremities
[Contraindications to beta-blockade]
alpha-adrenergic, V
Overdose of beta-adrenergic antagonist:
___cardia
___cardiac output
___tension
___shock
Bronch____
____intraventricular conduction of impulses
___glycemia - rarely
Brady
Low
Hypo
Cardiogenic
-ospasm
Prolonged
Hypo
TREATMENT:
___ ___ mcg/kg IV (0.5 mg IV) first
[Overdose of beta-adrenergic antagonist]
Atropine 7
TREATMENT:
Isoproterenol ___-___ mcg/min (with ___beta-blocker)
[Overdose of beta-adrenergic antagonist]
2-25, nonselective
Treatment:
Dobutamine (pure ___agonist) when beta-blockade is from a beta-blocker with ___ ___effects
pharmacologic treatment)
[Overdose of beta-adrenergic antagonist]
β1, no sympathomimetic
Treatment:
Glucagon (___-___mg)(drug of choice due to ____ action) and CaCl (250 mg to 1 gm) increase cardiac function independent of the blocked receptors.
[Overdose of beta-adrenergic antagonist]
1-10, independent, CaCl, increase
Treatment:
If heart rate does not ___ with drugs, a ___may be necessary.
[Overdose of beta-adrenergic antagonist]
increase, pacemaker
Treatment:
Hemodialysis – only for minimally ___-___, renally excreted ___ ___(refractory to pharmacologic treatment)
[Overdose of beta-adrenergic antagonist]
protein-bound, beta blockers
Isuprel overcomes competitive binding – requires much higher dose (___-___X) than when beta blockade is absent.
[Overdose of beta-adrenergic antagonist]
5-20
___and ____– avoid, as alpha1 vasoconstriction occurs at the high doses required to overcome the beta blockade
[Overdose of beta-adrenergic antagonist]
Epinephrine and dopamine
Glucagon – MOA is not via ___ receptors – stimulates ___ ___ and increases ___ ___ – especially effective in life-threatening bradycardia
[Overdose of beta-adrenergic antagonist]
beta, adenylate cyclase,
intracellular cAMP
Myocardial thresholds may be raised to prevent ___capture
[Overdose of beta-adrenergic antagonist]
electromyocardial
Increased ___stimulation due to ____-____ of beta receptors
[Acute withdrawal of beta-blockade]
sympathetic, up-regulation
Within ___-___hours
[Acute withdrawal of beta-blockade]
24-48
Profound ___tension, ___cardia, contractility
[Acute withdrawal of beta-blockade]
hyper, tachy
Avoid: ___ preoperative beta-blockade therapy
Infusion of propranolol ___mg/hr IV
[Acute withdrawal of beta-blockade]
continue
3
Treatment of hypertension:
Decrease ___, decrease ___
[Uses of beta-adrenergic antagonists]
HR, CO
Treatment of hypertension:
Decrease___ in larger doses
[Uses of beta-adrenergic antagonists]
contractility
Treatment of hypertension:
With____, prevention of ___ ___
[Uses of beta-adrenergic antagonists]
vasodilator, reflex tachycardia
Treatment of hypertension:
Decrease___, decrease ___, prevention of Na, water retention
[Uses of beta-adrenergic antagonists]
renin, aldosterone
Management of angina pectoris
Decreased myocardial oxygen consumption – ___, ___
[Uses of beta-adrenergic antagonists]
decreased HR, contractility
Post-myocardial infarction
Historically - Decreases ___ and ___
Increases chances of survival ___-___%
Begin within ___ to ___ days after MI and continue for 1-3 years
Within ___hours of onset of ___ may actually decrease infarct size and ___
[Uses of beta-adrenergic antagonists]
mortality and reinfarctions
20-40
5 to 28
12, infarct, dysrhythmias
