Cardiac 05 Cardiac Pharmacology Flashcards
What’s the purpose of the sympathetic system?
Activation of flight or fight response.
What’s the purpose of the parasympathetic system?
Maintain organ function and conserve energy
What 2 neurotransmitters do we want to know that are part of the sympathetic system?
- Norepinephrine
- Epinephrine
What are 2 receptors of the sympathetic system?
Adrenergic: alpha and beta
What neurotransmitter do we want to know in the parasympathetic system?
Acetylcholine
What are cholinergic receptors of the parasympathetic? (2)
nicotinic, muscarinic
Beta 1 receptor meds would affect the heart and do what?
Heart: increase conduction, velocity, and contractility
Beta 2 meds would affect what lungs in what way?
Lungs, leading to bronchial dilation and decrease secretions.
Delete
What receptors (2) would affect the vessels?
Alpha 1 and Beta 2, constriction or dilation may occur (??)
What is dopamine and how does it work?
- Natural occuring catecholamine and precurso to norepinephrine.
- Stimulation of dopaminergic receptor. Versatile drug with different effects depending on the concentration. It helps in positive inotropic effect and vasoconstriction.
What is the therapeutic use of norepinephrine?
- Endogenous catecholamine w/ inotropic and peripheral vasoconstriction effects. Used as first line drug for BP management.
What is phenylephrine and its effects?
- Powerful alpha agonist. Used when no beta simulation is wanted.
- Increase afterload, BP,SVR and PVR. Coronary vasoconstriction
What is epinephrine and it’s effects?
- Endogenous catecholamine.
- Powerful inotropic, peripheral vasoconstriction effects and inotropic effects. Increase mycoardial O2 consumption, incrase myocardial contractility.
Usually not used as a first line drug d/t profound vasoconstrictive effects.
What is vasopressin?
It’s a naturally occurring antidiuretic hormone. In unnatural high doses, it’s a non adrenergic peripheral vasoconstrictor.
What are the pharmacodynamics of vasopressin?
- Stimulation of smooth muscle
- Smooth muscle constriction: pallor of skin, nausea, intestinal cramps,
- Less constriction of coronary and renal vascular beds and vasodilation of cerebral vasculatore
- No skeletal muscle vasodialtion or increased myocardial O2 consumption during CPA cuz there’s no beta-adrenergic activity.
- Might enhance platelet aggregation in septic shock
How does vasopressin affect the hemodynamics? (3)
- Increase SBP, MAP, SVR
- Increase UO
How does epinephrine affect hemodynamics? (5)
- Increases HR, MAP, CO, SVR, PVR
- Pro arrhythmic
What is dobutamine and the therapeutic use?
- Synthetic catecholamine with selective beta adrenergic agonist properties. Class intotropic agent.
- Effect as positive inotropic for preload and afterload reduction. Used for + inotropic properities when vasoconstriction is NOT preferable.
Used in combo w/ another catecholamine or vasodilator.
What are the hemodynamic effects of dobutamine? (3) CO, SVR, HR
- Increase CO
- Mild decrease in SVR
- Increase in HR
What is milrinone?
Synthetic noncatecholamine agent that does not stimulate or block adrenergic receptors. Effects as a positive inotrope and vasodilator.
How does milrinone affect hemodynamics?
- Increase CO
- Decrease CVP, SVR, PAOP
- no significant effect on HR or BP
What is nicardipine used for? (2)
Class of drug?
It’s a calcium channel blocker used for antiHTN, chronic stable angina
What are the hemodynamic effects of nicardipine? SVR, BP, HR
- Decrease SVR and BP
- Reflex increase in HR
- Coronary artery dilation
Where are beta1 receptors located?
Heart
Where are beta2 receptors located?
bronchial and vascular smooth muscle
Where are Alpha1 receptors located?
Vessels
Where are dopaminergic receptors located?
Renal and mesenteric artery bed.
What receptors does phenylephrine hit?
Pure alpha1, vasoconstriction of most vessels. No beta receptors.
What receptors does norepinephrine hit?
HR, contractility, up or down?
Alpha1 and beta1. 2:1.
Helps with vasoconstriction, increase HR, contractility and conductivity.
What 3 receptors does epinephrine hit and the ratios?
alpha1: Beta1: Beta2
4:4:2
What 3 receptors does dopamine hit?
alpha1:beta1:beta2
2:4:1
What 2 receptors does Isoproterenol hit?
beta1:beta2
4:4
What’s the range dose for dopamine?
1-10mcg/kg/min
What’s the dose range of levophed?
2-10mcg/min
What’s the dose range of phenylephrine (neo synephrine)
40-60mcg/min
What is the range of epinephrine?
1-4mcg/min
What is the range of vasopressin?
0.2-0.9 U/min
What is the dobutamine range?
2-10 mcg/kg/min
How does milrone work?
By inhibiting the phosphodiesterase III enzyme. Effective as positive inotrope and vasodilator.
does not work on adrenergic receptors.
What are hemodynamic effects of milrinone?
Increase in CO.
Decrease in CVP, SVR, PAOP
No significant changes in HR or BP
What are milrinone range?
0.375 - 0.75 mcg/kg/min
What’s the range dose of nicardipine?
5-15mg/hr
How does nicardipine work?
Calcium Channel blocker, dilates coronary arteries and arterioles
Nitrates should not be taken with…
sildenafil
What are precautions that should be taken with nitroprusside?
- BP monitoring since it’s a strong vasodilator
- Thiocyanate toxicity if nitroprusside is used longer than 72 hours longer
- may cause hypoxia with intrapulmonary shunting
What kind of cardiomyopathy typically has mitral regurgitation?
dilated cardiomyopathy, d/t ventricular dilation and stretching of the mitral valve ring.
What does an S3 indicate in terms of HF?
Early indicator of LHF. Indicates systolic dysfunction. So med may be needed to help with contraction.
May need to decrease preload and increase contractility.
How would you listen to S3 and S4 sounds?
They’re low pitched, so bell of the stethoscope should be used. Best heart at mitral area/apex.
What is Ibutilide used for?
To convert acute onset a fib or a flutter to nsr
What drug category is used to block the renin-angiotensin-aldosterone system in the heart?
Angiotensin-converting enzyme inhibitors. ACE
What kind of blocker is carvedilol?
An alpha and noncardioselective beta blocker
What kind of blocker is labetalol?
Alpha and noncardioselective beta blocker typically used for HTN
What kind of blocker is propranolol?
Noncardioselective beta blocker, doesn’t block alpha receptors though
What are Class I drugs?
sodium channel blockers. Slows electrical impulses in the heart muscle
e.g disopyramide, flecainide, mexiletine, propafenone, quinidine
What are class II drugs?
Beta blockers. Slows down the HR.
e.g -olol
What are Class III drugs?
K channel blockers.
e.g amiodarone, sotalol here too, dronedarone
What are class IV drugs?
Calcium channel blcoekrs
- -amil, diltiazem
What is Dantrolene? Dangers of it?
Muscle relaxant. When used with calcium channel blockers, can cuase v fib.
