Pathopharm Exam 2-S4 Flashcards
This receptor affects the arteries more than veins.
-Increases vascular tone by vasoconstriction to increase Blood pressure?
Alpha-1 receptor
This receptor is found primarily on heart and increases heart rate and contractility.
-Also increases risk of arrhythmias?
Beta-1 receptor
This receptor is found in arteries and veins and inhibits adenyl cyclase to decrease norepinephrine release and increase parasympathetic outflow?
Alpha-2 receptor
This receptor causes smooth muscle relaxation and should be avoided with asthmatic patients?
Beta-2 receptor
This drug is an alpha-1 and alpha-2 agonist.
- Endogenous catecholamine.
- Arterial and Venous constriction
- Increase BP, SVR and PVR
- may slow HR due to baroreceptor mechanism
- Does not increase myocardial O2 consumption
- Dose not cross BBB
Norepinephrine (Levophed)
This drug is an alpha-1 agonist
- Causes vasoconstriction, bradycardia
- Coronary vasoconstrictor
- Increase BP, SVR, PVR, and afterload.
- May need to add dopamine to keep HR up.
- Often used in neurologic shock
- Contraindicated w narrow angle glaucoma
Neosynephrine (Phenylephrine)
This drug is a beta-1 agonist
- Synthetic catecholamine
- reduced preload and afterload
- increases contractility, CO, HR and BP.
- Also increases myocardial O2 demand.
- May drop BP if patient is dehydrated.
Dobutamine
This drug is a beta-1 and alpha-1 agonist and works at DA receptors
- First line agent for shock
- Naturally occurring catecholamine
- Precursor to norepi
- Dilates/increases renal blood flow
Dopamine
Low dose Dopamine affects what?
1-3 mcg/kg/min
Renal, coronary and cerebral vasodilation. Increased urinary output
Mid dose Dopamine affects what?
3-10 mcg/kg/min
Beta-1 stimulation with positive ionotropic effect.
Increased HR and small BP increase
High dose Dopamine affects what?
>10 mcg/kg/min
Alpha-1 stimulation with potent vasoconstriction.
Increased BP and increased SVR
This drug is a beta-1 and alpha-1 agonist
- Endogenous catecholamine
- causes peripheral and global vasoconstriction
- Bronchodilation
- NOT first line treatment
- Increases cardiac contractility and O2 demand.
- Increased HR, MAP, CO, SVR, PVR
- Risk of arrhythmia development
- Systolic increase and diastolic decrease
- Does not cross BBB
Epinephrine
This drug is a VP-1 agonist
- ADH
- causes smooth muscle constriction
- Used in ACLS for pulseless VT and VF
- Less constriction at coronary and renal beds
- Vasodilates cerebral vasculature
- May enhance platelet aggregration in septic shock
- Increases BP, MAP, SVR, and UO
Vasopressin
This drug is a vasopressin analog, agonist at VP-1
- IV only
- Control of Low BP
- Used for patients who do not respond to Norepi
- Useful to treat bleeding esophageal varices
- avoid use in hypoxic patients
Terlipressin
This drug is a PDE-3 inhibitor
- Positive inotrope and vasodilator
- Cleared by liver, can accumulate with liver dz
- Increases cAMP causing increased Ca into cells to improve myocardial contractility and inhibit vasoconstriction.
- Increases CO
- Decreases CVP, SVR
Milrinone
This drug is indicated for severely low BP in septic or distributive shock
- very short half life (1 min)
- IV infusion only
- titrate BP to proper range
- May cause clots and DVTs
- Must be given with anti-clotting therapeutics
Angiotensin II acetate (Giapreza)
This drug is a Na/K ATPase inhibitor
- narrow therapeutic window
Used in systolic heart failure with decreased CO
- Used with atrial fib and SVT
- Increases Cardiac output
- Increases voltage at rest.
- Used more in outpatient PO
Digoxin
NE > EPI > DA > ISO
Alpha-1 agonist potency
EPI > NE > DA > ISO
Alpha-2 agonist potency
ISO > EPI = NE > DA
Beta-1 agonist potency
ISO > EPI > NE > DA
Beta- 2 agonist potency
ISO = NE > EPI > DA
Beta-3 agonist potency
Muscarinic receptor structure/function?
G-protein
Nicotinic receptor structure/function?
Ionophore
Alpha and Beta receptor structure/function?
G-protein
This drug is a selective central acting alpha-2 agonist
- analog of Clonidine but 7x more selective
- can be used as anesthetic
Dexmedetomidine (precedex)
This drug is last line treatment for HTN treatment
- Forms A-methyl NE
- False transmitter
- contraindicated with hepatic dz
- Decreases norepi release
Methyldopa
This drug is an Alpha-1 and Beta-1 agonist and mild at Beta-2
- causes peripheral norepi release
- relaxation of smooth muscle and cardiac stimulation and increased blood pressure.
- High abuse, can make meth
Ephedrine
This drug is an irreversible-covalent bind alpha-1 and alpha-2 antagonist.
- Lasts 3 days
- Most effective at smooth muscle and exocrine glands
- Pre-op treatment for pheochromocytoma to block HTNcrisis
- Oral
Phenoxybenzamine (Dibenzyline)
This drug is an alpha-1 and alpha-2 competitive antagonist.
- shorter duration of action than phenoxybenzamine
- used for pheochromocytoma diagnosis
Phentolamine (oraverse)
This drug is a selective alpha-1 antagonist
- used to treat HTN
- less risk of reflexive tachycardia than other alpha blockers
Prazosin (minipress)
Terazosin, Doxazosin, Alfuzosin, and Tamsulosin are all alpha-1 blockers than can be used to treat HTN and what else?
Benign prostatic hyperplasia (BPH)
This drug is a non-selective beta blocker beta-1 and beta-2.
- treats HTN, speaker nerves, angina
- contraindicated in shock, asthma, bradycardia
- bronchospasm side effect
Propanolol
Timolol is a non-selective beta blocker most often used for treating what?
Ocular hypertension and wide angle glaucoma
This drug is a non-selective Alpha-1, Beta-1 and B-2 antagonist.
- treating HTN
- contraindications with asthma and CHF
Labetalol
This drug is a non-selective Alpha-1, Beta-1 and B-2 antagonist.
- treating HTN
- Higher beta: alpha block than labetalol
- contraindications with bronchospasm, COPD, bradycardia
Carvedilol (coreg)
This drug is a selective Beta-1 antagonist
- treat HTN and angina pectoris
Metoprolol (lopressor)
This drug is a selective Beta-1 antagonist used to decrease BP and control ventricular arrhythmias
- side effects of alopecia
Acebutolol
This drug is a selective Beta-1 antagonist
- IV infusion due to short half life
- treatment of atrial fib or flutter, paroxysmal SVT
Esmolol
Sodium Channel blockers are which antiarrhythmic drug class?
Class Ia-Ic
Class Ia-Ic antiarrhythmic class?
Sodium Channel Blockers
Beta-adrenergic blockers are which antiarrhythmic drug class?
Class II
Class II antiarrhythmic class?
Beta-adrenergic blockers
Calcium Channel blockers are which antiarrhythmic drug class?
Class IV
Class IV antiarrhythmic class?
Calcium Channel blockers
Class III antiarrhythmics?
Potassium Channel blockers
What is the normal AV nodal delay in ms?
0.15 seconds or 150 ms
What neurotransmitter shortens the conduction time of action potential through AV node propagation?
Acetycholine (Catecholamines)
During the cardiac cycle which structure directly delivers action potential to the ventricular myocardium?
Purkinje fibers
The cardiac electrical impulse normally begins spontaneously in the SA node because of what?
It depolarizes more rapidly than other automatic cells of the heart.
SA node is first
Which period follows depolarization of the myocardium and represents a period during which no new cardiac potential can be propagated?
Absolute Refractory Period
Where in the heart are the receptors for neurotransmitters located?
Myocardium and coronary vessels
What enables electrical impulses to travel in a continuous cell to cell fashion in myocardial cells?
Intercalated disks
Older children with unrepaired cardiac septal defect experience cyanosis because of which factor?
- Right to left shunt
- Left to right shunt?
Right to left shunt
The atria squeeze in which sequence?
Top down contraction
The ventricles squeeze in which sequence?
Bottom up contraction
The purkinje fibers stimulate what first?
The apex
Transmembrane potential is determined by which 3 ionic gradients?
Na
K
Ca
The maintenance of electrogenic ionic gradients and membrane potential comes from what?
NA/K ATPase pump
3 Na out for 2 K in
This ionic gradient is responsible for the resting membrane potential, it is relatively permeable?
K
Potassium. -90mv membrane potential
Which phase corresponds to Na channel activation with rapid flow in?
Phase 0
Voltage now +10mv
Which phase corresponds to an early repolarizing K current in which Na channels close and K channel open?
Phase 1
Which phase is a combination of inward depolarizing Ca balanced by an outward repolarizing K current?
Phase 2
Which phase is repolarizing due to outward K current increasing which inward Ca current decreases?
Phase 3
Which phase is a balance between inward Na current and outward K current. The membrane potential drifts towards threshold?
Phase 4
Spontaneous depolarization is also called what?
Automaticity
Any change to which phase alters conduction?
Phase 4
Electrical gradient wants to _____ potassium which the concentration gradient wants to ______ potassium?
Electrical- hold in
Concentration- push out
Ectopic pacemaker is facilitated by what?
Treated by what?
Facilitated by hypokalemia
Increasing potassium slow/stop ectopic activity
Increasing the maximum diastolic membrane potential can diminish automaticity by which two drugs?
Adenosine
Acetylcholine
Decreasing the slope of phase 4 depolarization can diminish automaticity by which drugs?
Beta blockers
Increasing the action potential duration can diminish automaticity by which drugs?
K channel blockers
AIDS
Raising the membrane threshold potential can diminish automaticity by which drugs?
Na channel blockers and
Ca channel blockers
Which condition is caused by an accessory conduction pathway?
Wolf-Parkinson-White syndrome
Which drugs prolong nodal refractoriness and slow conduction?
Can treat WPW syndrome
Ca channel blockers
Beta blockers
Digitalis glycosides
Na channel blockers
This drug class is primarily used to slow the rate of action potential rise and prolong ventricular effective refractory period?
Sodium channel blockers Ia
This drug is a class Ia
- Na channel blocker (activated only)
- Used to terminate reentry arrhythmia
- Antimalarial and antipyretic effects
- Must be given slow IV
- Accumulated in hepatic/renal dz pts
- can also block K channels
- Affects Phase 0 and Phase 4
- treat WPW syndrome
- Cinchonism (N/V/D, blurred vision)
- Antimuscarinic action on heart
- Can develop Torsades de Pointes
Quinidine
This drug is a class Ia
- Na channel blocker
- long term use associated with Lupus
- Cardioactive metabolite (NAPA) may lead to Torsades de Pointes
- Does not exhibit antimuscarinic activity like Quinidine
- Ganglionic blocking activity
Procainamide
Procainamide-induced Lupus syndrome occurs more frequently in which population?
Slow acetylators
Europeans
This drug is a class Ia
- Na channel blocker
- Greater anti-muscarinic effects
- Used for ventricular arrhythmias
- Not an alpha- adrenergic blocker
Disopyramide (Norpace)
This drug is a class Ib
- Na channel blocker
- Blocks activated and inactivated
- Reduces the phase 4 slope and increases threshold
- requires IV administration due to extensive first pass
- Rapidly dissociates in normal tissue (low affinity)
- Remains bound in ischemic tissue (high affinity)
- Major side effect is Seizure in rapid administration and cardiac depression
Lidocaine (Xylocaine)
This drug is a class Ib
- Na channel blocker
- Chronic treatment of Ventricular tachyarrhythmias
- Amine analog of Lidocaine
- Oral administration
Mexiletine Hydrochloride
This drug is a class Ib
- Na channel blocker
- effective in suppression of ventricular arrhythmias associated with digitalis toxicity
- Least effective Na channel blocker
- Shortens QT more than any agent
- Can cause CNS disturbances (sedation, nystagmus, confusion, ataxia).
- Causes hirsitism (hair growth)
Phenytoin (Dilantin)
Barbituates do what to phenytoin levels?
Lower phenytoin levels due to metabolizing enzyme induction
Warfarin, Isoniazid do what to phenytoin levels?
Increase phenytoin levels due to metabolism inhibition
This drug is a class Ib piperazine deriv
-also blocks K and Ca conductance
- used to treat chronic angina
- decreases late Na inward current and intracellular Ca conc
- Increases refractory period used for ventricular arrhythmias
- Metabolized by CYP3A4 avoid grapefruit juice
Ranolazine (Ranexa)
This drug is a class Ic
- Na channel blocker
- more effective than Ia or Ib
- suppresses pvcs and v-tach
- effective in managing atrial tachyarrhythmias
- effective in WPW syndrome treatment
- Reserved for management of life threatening arrhythmias.
- Not 1st line treatment
- Proarrhythmic dangerous with MI patients
Flecainide Acetate
This drug is a class Ic
- Na channel blocker
- weak beta blocker
- weak Ca channel blocker
- active metabolite via liver metabolism
- Proarrhythmic dangerous with MI patients
Propafenone (Rythmol)
This drug is a class II
- beta blocker
- decreases the slope of phase IV
- Increases AV conduction time
- treatment of atrial flutter and atrial fibrillation
- can lead to bronchospasm, worsen CHF
Propranolol (Inderal)
This drug is a class II
- beta blocker
- very short acting (IV admin)
- cardioselective
- decreases the slope of phase IV
- Increases AV conduction time
- treatment of atrial fibrillation with RVR
Esmolol (Brevibloc)
This drug is a class III
- potassium channel blocker
- delays repolarization and prolongs action potential
- increases refractory period
- orthostatic hypotension with chronic use
- increased ventricular action potential duration
- Initial catecholamine release
- used to manage serious ventricular arrhythmias caused by lidocaine or procainamide
- Not first line treatment
Bretylium Tosylate
This drug is a cross between class I and III
- K channel blocker
- Na channel blocker
- prolongs action potential duration
- Treatment of ventricular arrhythmias
- Can cause hypo/hyperthryoidism due to iodine content
- Long term therapy can lead to pulmonary fibrosis (fatal)
- Postoperative pulmonary edema
- sinus arrest (risky drug)
Amiodarone (Nexterone)
This drug is a cross between class I and III
- Increasing refractory period
- alternative to amiodarone for atrial fib/flutter treatment
- Black Box warning with CHF
- greatest effect on K channels
Dronedarone (Multaq)
This drug acts as a class II and III
- Nonselective beta blocker
- K channel blocker
- Prolongs refractory period
- may cause HTN or vasospasm
- Avoid in asthmatics
- treats atrial fib/flutter
Sotalol (Betapace)
This drug is a class V
- G-protein coupled
- activates acetylcholine K current
- decreases action potential duration
- Rapidly terminates SVT
Adenosine
This drug is a class IV
- Ca channel blocker
- blocks the inward Ca current to slow conduction through AV node and decrease phase IV depolarization
- Main action on the heart
- used to convert atrial fib/flutter to NSR
- Hypotension side effect
- constipation
Verapamil and
Diltiazem (Cardizem)
Which classes/drugs are ideal to treat Atrial fibrillation?
Calcium channel blockers- Verapamil/Diltiazem
Beta blockers- Propranolol
Digitalis glycosides- Digoxin
Which classes/drugs are ideal to treat and maintain Normal Sinus Rhythm?
Class Ia Sodium channel blockers
Quinidine and Procainamide
Which classes/drugs are ideal to treat Paroxysmal SVT?
- Valsalva maneuver
- Alpha receptor agonist
- Digoxin
Adenosine, Verapamil, Diltiazem, Esmolol or Cardioversion.
Thiazide diuretics work in this part of the kidney?
Distal renal tubule
Hydrochlothiazide
Potassium sparing diuretics work in which part of the kidney?
Late distal tubule and Collecting duct
Amiloride, Triamterene, Spironolactone
High Ceiling Loop diuretics work in which part of the kidney?
Thick ascending limb in loop of Henle
Lasix, Bumetanide
Which beta blocker’s vasodilation affect includes potentiating Nitric Oxide?
Nebivolol (Bystolic)
Which drug works primarily to vasodilate the arteries thus having greater effect on diastolic BP?
Hydralazine
Minoxidil was once an orally active form of direct arteriole smooth muscle relaxation for HTN treatment but is now used for what?
Hair growth in women
This drug has a Ferrous iron center complex with 5 cyanide (44% by weight), requires IV administration due to short duration. Requires A-line monitoring and may result in coronary steal?
Nitroprusside
What is the active mediator responsible for direct nitroprusside vasodilating effect?
NItric oxide
The body sulfur stores can detoxify how many mg of nitroprusside into cyanide ions?
50mg
Which drug is most often used for hypertensive emergencies?
Nitroprusside
Which class of drugs can potentiate NMBA agents and make them last longer?
Calcium channel blockers
This drug is a diagnostic marker for ALL leukemia?
Entresto
Neprilysin Inhibitor
