ANS Pharm! Flashcards
What are some traits about NEO?
RBF: decreased
MAP: ^^
Metabolism: MAO
Receptor: alpha 1
Use: hypotension
What are some traits about Clonidine?
RBF: no change
MAP: decreased
Metabolism: 50% liver/50% unchanged
Receptor: a2
Use: HTN (rebound HTN with abrupt stop)
What are some traits about dexmedetomidine?
RBF: no change
MAP: decreased
Metabolism: CYP liver
Receptor: a2
Use: sedation, analgesia, (may cause bradycardia and hypotension)
What may occur following the administration of phenylephrine?
Significant bradycardia
What is the alpha 2: alpha 1 ratio in clonidine?
200:1
What is the alpha 2: alpha 1 ratio in precedex?
1600:1
What type of action does clonidine have at the alpha 2 receptor?
Partial agonist
What type of action does precedex have at the alpha 2 receptor?
Full agonist
What aspect of the nervous system do alpha 2 agonist work?
Locus coeruleus and dorsal horn
Precedex produces more than clonidine
What does abrupt discontinuation of clonidine cause?
Rebound HTN, tachycardia, and arrhythmia
What drug can reduce emergence and agitation in both adults and children?
Precedex
What are some traits about epinephrine?
RBF: decreased
MAP: ^
Airway resistance: decreased
Metabolism: reuptake; MAO, COMT
Receptor: B1 > B2, a1
Use: shock, anaphylaxis, ACLS
What are some traits about norepinephrine?
RBF: decreased (most)
MAP: ^^^ (most)
Airway resistance: no change
Metabolism: reuptake, MAO, COMT
Receptor: a1, B1 >nB2
Use: shock, vasoplegia
What are some traits about dopamine?
RBF: ^^^
MAP: ^
Airway resistance: no change
Metabolism: reuptake; MAO and COMT
Receptor: B1 > B2, a1
Use: shock
What are some traits about isoproterenol?
RBF: deceased
MAP: ^
Airway resistance: decreased sig.
Metabolism: COMT
Receptor: B1 > B2
Use: drug pacing
What are some traits about dobutamine?
RBF: ^^
MAP: ^
Airway resistance: no change
Metabolism: COMT
Receptor: B1 > B2 > a1
Use: cardiogenic shock, stress test
What are some traits about ephedrine?
RBF: decreased
MAP: ^^
Airway resistance: decreased
Metabolism: liver (^ % Renally unchanged)
Receptor: a, B, indirect
Use: hypotension
What will organs with a higher incidence of B2 see if epi is administered?
Dilation (skeletal muscle)
What will organs with a higher incidence of alpha 1 see if epi is administered?
Vasoconstriction
(Mesentery/kidneys)
What does a lower dose of epi favor?
Beta stimulation
What does a higher dose of epi stimulate?
Alpha effects
What epinephrine reversal?
Converts the pressor response (mediated by a receptors) to a depressor response (mediated by B2 receptors)
Which med is a first line therapy in distributive shock that otherwise may be refractory to hypotension?
NE
What does low-dose dopamine do?
< 3 mcg/kg/min
Stimulates D1 receptors ~ resulting in vasodilation and increased renal and splanchnic flow
What does moderate dose dopamine do?
3-8 mcg/kg/min
Stimulates a1 and B1 adrenergic receptors in the heart and periphery, this increasing contractility
What does high dose dopamine do?
> 10 mcg/kg/min
Acts as a pure a1 agonist > increased BP
Does dopamine prevent/reverse kidney injury or failure?
NO!! Data does not support that.
What is isoproterenol derived from?
Dopamine!
Potent B1 and B2 activity (2-3 x the potency of epi)
***no alpha activity
What does isoproterenol tend to precipitate?
Supra ventricular and ventricular arrhythmias (hence why it is given in EP lab for SVT)
What is dobutamine derived from?
Isoproterenol!
What does dobutamine act as?
“Pharmacological stress test”
Why is dobutamine sometimes used in patient with pulmonary HTN?
Increase inotropy as it decreases pulmonary arterial pressures and PVR through its B2 stimulation
How does ephedrine elicit it’s indirect effect?
Results from the endo utopia of ephedrine into the adrenergic presynaptic terminals ~ displaying NE from secretory vesicles
What is seen with repeat administrations of ephedrine?
Tachyphylaxis
This results from depletion of the presynaptic norepinephrine
***this is why it is NOT given as an infusion
Does ephedrine cross the BBB?
Yes. ~ mild stimulating effects which may lead to misuse
What are B2 agonists commonly used for?
Airway dx!
COPD, asthma, airway reactivity
What are considered short acting B2 agonists?
Albuterol, terbutaline, LR albuterol
What are considered long acting B2 agonist drugs?
Salmeterol and formoterol
What are some side effects of B2 stimulation?
Tremor, anxiety, restlessness
What happens with escalated dosing of B2 agonists?
B2 selectivity wanes and B1 effects (tachycardia and arrhythmias) become more apparent
How does B2 agonists work?
^cAMP (BUT in this region) increased cAMP reduced Ca levels leading to smooth muscle relaxation
***happens in uterine musc too!
What is the black box warning to longer-acting B2 selective agents?
Due to a risk of asthma-related deaths.
***could be noted hyperresponsivenss after continuous use.
What are examples of two nonselective alpha 1 and alpha 2 antagonists?
Phenoxybenzamine
Phentolamine
Which alpha antagonist is a NONcompetitive antagonist?
Phenoxybenzamine
The bonding of this receptor is irreversible!!
**oral administration
What is phenoxybenzamine exclusively used for?
Preoperative management of pheochromocytoma ~ prevents episodic HTN and normalizes BP
What is the BEST treatment for phenoxybenzamine-induced severe hypotension?
Vasopressin and fluids! (NE and Neo will be useless)
What is phentolamine?
COMPETITIVE nonselective alpha receptor antagonist
**it can be overcome by Neo and NE
How is Phentolamine administered?
Potent, rapid acting vasodilator. It can cause baroreceptor-mediated bradycardia!!!
***use in extreme caution with patients with flow-limited CAD
Can Phentolamine be given as a local injection?
Yes! Especially after extravasation of a vasoconstrictor like NE or Epi.
What other receptor does phentolamine have an affinity for?
5-HT ~ this will stimulate stomach acid secretion
What is prazosin?
Highly selective alpha 1 receptor antagonist
1000:1 (alpha 1 vs alpha 2)
What are the side effects to prazosin?
Postural/orthostatic hypotension
What is Terazosin?
Less potent and longer acting than prazosin.
It’s main use is in treating prostate hypertrophy! (There are a large number of alpha 1 receptors there) ~ Anesthetic-induced hypotension may be exacerbated.
What is Yohimbe?
Primary a drug for males. ~ selective alpha 2 antagonist wildly used for sterile dysfunction, athletic performance, weight loss, HTN, etc…
**illegal in US
What are the main indications for Beta blocker use?
HTN
SVT
Afib
blunting of a Hemodynamic response
Reducing myocardial O2 consumption
Which two B-blockers have membrane stabilizing activity?
Propranolol and acebutolol
(These have MSA ~ inhibits or abolishes action propagation across the cell membrane)
Which B-blockers possess intrinsic sympathomimetic activity?
Pindolol, labetalol, and acebutolol
Exert a partial stimulating (agonist) action at the B receptor
What is the prototypical NONselective B-blocker?
Propranolol
What are some side effects of Propranolol?
Can produce bronchoconstriction (d/t it’s nonselectivity)
May aggravate Raynaud’s
What are some other examples of NONselective B-Blockers?
Carvedilol, nadolol, pindolol, sotalol, and timolol
What are some examples of CARDIOSELECTIVE B-Blockers?
Metoprolol
Atenolol
Acebutolol
Esmolol
Bisoprolol
Which BB is metabolized by the kidney?
Atenolol
What is the first-line drug for rapid perioperative control of HR and BP?
Esmolol
How is esmolol metabolized?
Nonspecific esterases in the red blood cell
What are the two main NONselective adrenergic antagonists?
Labetalol and Carvedilol
What is the ratio of B to alpha block with labetaolol
7:1
What is labetolol primarily used for?
Acute HTN
Which BB has both antioxidant and anti-inflammatory properties?
Carvedilol
What is a common self-administered cholinergic?
Nicotine!
Which ganglia are activated with nicotine?
Both SNS and PNS!!! POSTganglionic neurons are activated by ACh released from PREganglionic receptors
Why is Nicotine a concern in the cardiovascular system?
Nicotine’s effects will be unopposed because there is insignificant PNS regulation
What medication is used to provoke bronchoconstriction, increased airway secretions, and peak expiratory flow rate?
Methacholine!
It’s used to identify reactive airway disease in those who do not have apparent signs of asthma.
What medication is used to treat nonobstructive urinary retention in the postoperative period?
Bethanachol
Which two cholinergic agonists produce miosis and have applications in treat glaucoma?
Carbamylcholine
Pilocarpine
What are some traits about atropine?
HR: ^^^ (most)
Smooth musc relax: ^^
Sedation: ^^
Mydriasis: ^
Antisialagogue: ^
Prevent Motion sickness: ^
Decrease gastric secretion: ^
Structure: tertiary amine
BBB: yes
What are some traits about scopolamine?
HR: ^
Smooth musc relax: ^
Sedation: ^^^
Mydriasis: ^^^
Antisialagogue: ^^^
Prevent Motion sickness: ^^^
Decrease gastric secretion: ^
Structure: tertiary amine
BBB: yes
(Remember MAPS ~ things scopolamine is best at ~ Mydriasis, Antisialagogue, Prevention of motion sickness, and Sedation)
What are some traits about Glyco?
HR: ^^
Smooth musc relax: ^^
Sedation: 0
Mydriasis: 0
Antisialagogue: ^^
Motion sickness: 0
Decrease gastric secretion: ^
Structure: quaternary Amine
BBB: no
What two antimuscarinics are considered belladonna alkaloids?
Atropine
Scopolamine
What can low-dose atropine cause?
Bradycardia! This happens by blocking M1 receptors on preganglionic parasympathetic fibers
What is the catchy phrase about anticholinergic syndrome?
Dry as a bone
Red as a beet
Blind as a rat
Hot as a hare
Mad as a hatter!
What medication reverses anticholinergic syndrome?
Physostigmine!! 1-2 mg
Ir also crosses the BBB cometitively reversing the effect
Which calcium receptor/channel do CCB target?
L type Ca channels
What are the 3 types of CCB?
Dihydropyridines
Benzothiazepines
Phenylalkylamines
What are examples of dihydropyridines?
Nifedipine, Nimodipine, nicardipine, and clevidipine
What is an example of a benzothiazepines?
Diltiazem!
The both have Zs in their name!
What is an example of a phenylalkylamine?
Verapamil
Which two CCB are better for controlled HR or contractility?
Verapamil and diltiazem
In what order do CCBs IMPAIR contractility?
Verapamil > nifedipine > diltiazem > nicardipine
In a patient with reduced EF, what medication would be best to preserve contractility while reduced HR?
Diltiazem
What medications are best used for treatment of HTN from elevated SVR?
Nifedipine and nicardipine
What is the only CCB that is proven to reduce M&M from cerebral vasospasm?
Nimodipine
Which CCB is also useful as a coronary antispasmodic?
Nicardipine
Do CCB produce great arterial or venous relaxation?
Arterial!!!
**they preserve preload while decreasing afterload
What is useful in treating angina/MI in those who may be unable to tolerate B1 antagonists?
Verapamil
Which CCB is highly selective for arterial smooth muscle with negative chronotropic or inotropy effects?
Clevidipine
What drug is useful in treating acute HTN, even in the setting of pheochromocytoma and intracerebral hemorrhage?
Clevidipine
Which drug does not improve or maybe even worsen mortality in those with acute MI?
Nifedipine
What drug is often prescribed for Raynaud’s?
Nifedipine
Which CCB is best with CHRONIC HTN?
Nicardipine
Which vasodilator dilates stenotic coronary arteries?
Nitroglycerin
Which vasodilator produces coronary steal?
Nitroprusside
Which vasodilator activates K-ATP channels?
Hydralazine
Which vasodilator causes hypertrichosis?
Minoxidil
What are some traits about nitroglycerin?
Action: venodilator with reduced afterload
Dose: 5-100 mcg/min
Onset: 2-5 mins
Duration: 5-10 mins
Notes: large coronary arteries may dilate; liver metabolism
What are some traits about Nitroprusside?
Action: reduces AFTERLOAD and PRELOAD
Dose: 0.3-10 mcg/kg/min
Onset: seconds
Duration: < 5 mins
Notes: potential for cyanide toxicity; liver metabolism
What are some traits about hydralazine?
Action: arterial smooth muscle dilator
Dose: 2.5-20 mg
Onset: 2-20 mins
Duration: up to 12 hrs!
Notes: patience with dosing d/t slow onset AND offset. Don’t burn yourself; liver metabolism
What was nitroglycerin first used for?
Dynamite!
The vasodilators effect of nitroglycerin is greater on what?
Venues!
How does NTG exert its action?
Liberation if nitric oxide
How does NTG improve the balance of O2 supply?
Direct coronary vasodilator and system effects (lowers preload)
What med is an excellent first-line treatment for cardiac ischemia?
NTG ~ dilates even stenotic vessels, preventing vasospasm
Why isn’t Nitroprusside used in MI tx?
It can produce coronary steal! Redistributing blood away from ischemic sites
Is reflex tachycardia worse with Nitroprusside or NTG?
nitroprusside ~ it’s a great arterial dilator
What is produced in SNP metabolism?
Cyanide
This inhibits aerobic metabolism
**Also bonds with hemoglobin to form methemoglobin and binding to sulfur to form thiocynate
What is the action of hydralazine?
Activation of K(ATP) channels ~ reducing intracellular Ca.
Which medication is now used for topical hair loss?
Minoxidil
What are the PDE5 inhibitors?
Sildenafil
Tadalafil
Vardenafil
How do PDE5 inhibitors work?
Increase levels of cGMP ~ this enhances nitric oxide vasodilation
**esp in the lungs and penis
Great to promote pulmonary vasodilation and decrease pHTN
What are examples of PDE4 inhibitors?
Roflumast, apremilast, ibudilast
How do PDE4 inhibitors work?
They increase levels of cAMP ~ this causes airway smooth muscle relaxation in those hyperactive airways .
(Also work for treating inflammatory states)
What is an example of a PDE3 inhibitor?
MILRINONE and cilostazol
How does PDE3 inhibitors work?
They increase levels of cAMP and cGMP ~ this increases inotropy in the heart and relaxation of vascular and airway smooth muscle.
Also called inodilators
how do PDE5 inhibitors affect platelet function?
They prevent platelet aggregation
What are vasopressin’s endogenous roles?
Water, osmolar, and BP homeostasis
What are ACEi best suited for?
HTN r/t increased renin production
***first lien therapy for HTN, CHF, mitral regurge, and LV dysfunction
What is the main side effects of acei?
> Dry cough ~ blocked degradation of bradykinin (which is a pulmonary inflammatory mediator)
> Angioedema > blocked degradation of bradykinin
> profound Hypotension that is refractory to neo, NE, or ephedrine
What are ARBs?
Angiotensin receptor blockers
Have a greater affinity for AT1 receptors
***ACE inhibitors work on both AT1 and AT2 receptors
Which medications provide renal protection for patients with DM?
ARBs
How do volatile anesthetics affect the EKG waveform?
They all prolong the QT interval d/t inhibition of K+ efflux that normally causes repolarization
What type of antiarrhythmic is lidocaine?
1B
What enzyme converts angiotensinogen to angiotensin 1?
Renin
What determines the HR of a transplanted heart?
Intrinsic rate of the SA node (100-120)
What type of drugs must be given in a patient with a transplanted heart?
Medications that DIRECTLY stimulate the SA node
(Epi, isuprel, glucagon)
Do carotid massages or the valsalva maneuver have any effect on the denervated heart?
No!
What are Paragangliomas?
Neuro endocrine tumors that arise from neural crest cells.
(Similar to pheochromocytoma, BUT exist outside of the adrenal gland)
**location determines S&S
Although paragangliomas rarely secrete vasoactive substances, if they did, what is the most common?
NE
What medication is used to treat carcinoid-like syndrome?
Octreotide
What is multiple system atrophy?
Degeneration and dysfunction of diverse central system structures (such as basal ganglia, cerebella’s cortex, locus coeruleus, pyramidal tracts)
**this was formally called shy-drager syndrome
What are S&S of multiple system atrophy? Aka Shy-Drager syndrome?
Urinary retention
Bowel dysfunction
Impotence
Postural hypotension
Failure of baroreceptors to produce an increase in HR or vasoconstriction in response to hypotension
When does death from cerebral ischemia (associated with prolonged hypotension) occur?
Within 8 years
Which antiemetics have anticholinergic properties?
Benadryl
Promethazine
