Cardiac Week and Noche Flashcards
Furosemide Trade name
Lasix
Furosemide drug class
Diuretic
Furosemide mechanism of action
Loop diuretic - main location of action is thick ascending limb of loop of Henle - Block Na+-K+-2Cl transporter in luminal membrane of loop of Henle preventing reabsorption of Na+ from tubular lumen -> decrease Na+ in medullary interstitial -> decreased osmolary gradient -> decreased urine concentration -> decreased H2O retention -> decreased blood volume -> decreased blood pressure
furosemide fx
- diuretic activity SA treat -congestive cardiomyopathy - pulmonary edema -hypercalcuric nephropathy - uremia - adjunct therapy in hyperkalemia - occasionally used as antihypertensive agent Cattle - udder edema Racehorses - reduce EIPH (exercise-induced pulmonary hemorrhage)
furosemide side effects
- fluid and electrolyte abnormalities - prerenal azoetemia - hyponatremia - hypocalcemia -hypokalemia -hypomagnesmia
enalapril trade name
Vasotec
enalapril drug class
ACE inhibitior
enalapril mechanism of action
- converted by liver to active compound enalprilat which competes with angiotensin I for ACE (angiotensin converting enzyme) (ACE has higher affinity for Enalaprilat than angiotensin I) -> prevents formation angiotensin-II which is a vasoconstrictor - decreased angiotensin-II [] -> decreased aldosterone secretion and plasma renin activity increased - decreases total peripheral resistance, pulmonary vascular resistance, mean arterial and R atrial pressures, and pulmonary capillary wedge pressure - increase renal blood flow and decrease glomerular efferent arteriole resistance
enalapril fx
- adjunctive therapy of heart failure (CHF) - decrease efferent glomerular resistance, reduce proteinuria and have renoprotective effects, can use for adjunct treatment idiopathic glomerular nephritis - CRF (chronic renal failure) - protein-losing nephropathy - hypertension accompanying kindey dx
enalapril side effects
- GI distress - weakness - hypotension - renal dysfx - hyperkalemia - can cause coughs
Diltiazem trade name
Cardizem, Dilt-cd
Diltiazem Drug class
Ca2+ channel blocker
Diltiazem Mechanism of Action
binds to L-type Ca2+ channels preventing Ca2+ entry into cell -> inhibit cardiac and vascular smooth muscle contractility dilating main systemic and coronary artieries; TPR, BP, cardiac afterload all = reduced - Slows AV node conduction and prolongs refractory time
Diltiazem fx
- termination for supra ventricular(atrial) tachycardia - suppress atrial premature complexes -> a-fib - decrease ventricular rate associated with atrial fibrillation
Diltiazem side effects
- bradycardia - hypotension - GI disturbances
Pimobendan trade name
Vetmedin
Pimobendan drug class
inodilator
pimobendan mechanism of action
- inhibition of phosphodiesterase III (PDE III) -> increased inotropy and arteriodilation - increases intracellular Ca2+ sensitivity on troponin C making -> enhancement cardiac contractility w/o inc in myocardial O2 consumption bc does not increase intracellular Ca2+ levels (Ca2+ sensitization -> increased ionotrophy)
pimobendan fx
- treat CHF secondary to DCM or chronic mitral valve insufficiency in dogs or myxomatous/ degernative mitral valve dx
pimobendan side effects
- GI - may inc development of arrhtymias
Spironolactone trade name
aldactone
spironolactone drug class
Mineralocorticoid antagonist
spironolactone mechanism of action
competitively binds mineralocorticoid receptor -> release heat shock protein 90 -> inhibits production of aldosterone-induced proteins and blocks effects of aldosterone ie -> dec Na+ uptake b/c aldosterone normally increases synthesis of lumina Na+ channels and increases K+ channels increasing K+ secretion driving force secondary to Na+ secretion so if inhibit aldosterone inhibit the luminal Na+ channels and in turn inhibit that secondary K+ secretion ** At low doses does not have diuretic effects**
spironolactone fx
- CHF patients not responding to furosemide and ACE inhibitors adequately - K+ sparing diuretic (use in CHF if hypokalemic) - treatment of ascites
spironolactone side effects
-GI - dehydration - hyperkalemia
albuterol trade name
proventil, accuneb
albuterol drug class
beta 2 adrenergic agonist
albuterol mechanism of action
stimulates production of cAMP by activation of adenyl cyclase via Gs -> relaxation bronchial, uterine, and vascular smooth muscle; beta 2 adrenergic agonist
albuterol fx
alleviate brochospasm or cough
albuterol side effects
- inc HR - tremors - CNS excitement (nervousness) - dizziness - decreased serum K+ values possible
epinephrine trade name
Adrenaclick, EpiPen, Twinject, Medihaler-Epi
epinephrine drug class
hormone and adrenergic agonist
epinephrine mechanism of action
endogenous adrenergic agent w/ alpha and beta activity -> - relaxation smooth muscle in bonchi and iris - antagonizes effects histamine - inc glycogenolysis - raise blood sugar - give rapidly IV -> inc systolic BP - give slow IV -> modest rise systolic pressure and dec diastolic pressure - dec TPR bc beta effects
epinephrine fx
From notes: - cardiac arrest/ heart block - acute anaphylactic reactions (counteract hypotension and bronchospasm) - combine with local anesthetics to retard removal of anesthetics - control bleeding (apply topically) -treatment for anaphylaxis or cardiac resuscitation - can add to local anestetics to retard systemic absorption and prolong effect
epinephrine side effects
- anxiety - tremor - excitablity - V+ - hypertension (overdose) - arrhythmias - hyperuricemia (excess of uric acid in blood) - lactic acidosis (buildup of lactate in body) - EPINEPHRINE REVERSAL IF GIVEN W/ ALPHA ADRENERGIC ANTAGONISTS (will -> dec BP not inc)
isoproterenol trade name
isuprel, medihaler-iso
isoproterenol drug class
beta adrenergic agonist
isoproterenol mechanism of aciton
B1 and B2 adrenergic agonist; isoproterenol stimulates B-adrenergic receptors of intracellular adenyl cyclase which catalyzes conversion of adenosine triphosphate to cAMP -> inc cAMP levels-> -inc inotropism and chronotropism, - relax bronchial smooth muscle - peripheral vasodilation - +/- inc perfusion to skeletal muscle
isoproterenol fx
From lecture: - cardiac arrest/ heart block From plumbs: - treat acute bronchial constriction - treat cardiac arrhythmias (complete AV block) - occasionally used as adjunctive therapy in shock of HF
isoproterenol side effects
- tachycardia - anxiety - tremors - excitablity - headache - weakness - V=
norepinephrine trade name
levophed
norepinephrine drug class
neurotransmitter and adrenergic agonist
norepinephrine mechanism of action
- directly stimulates adrenergic receptors strong affinity for alpha than beta receptors (GPCRs) - also some B1 activity - acts as peripheral vasoconstrictor (a) and inotropic cardiostimulant and coronary artery dilator (b) -> TPR inc -> inc BP - high doses can -> decreased perfusion to vital organs, skin, and skeletal muscle
norepinephrine fx
- treat profound hypotension (especially septic shock or post-cardiac arrest hypotension due to vasodilation) - cardiac stimulant, raise BP
norepinephrine side effects
- if used w/o blood volume replacement can -> dec renal perfusion and urine output, poor systemic blood flow despite “normal” pressure - arrhythmias - seizures
phenylephrine trade name
phenylephrine
phenylephrine drug class
alpha adrenergic agonist
phenylephrine mechanism of action
- a1 seletive - predominantly post-synaptic alpha-adrenergic effects at therapeutic doses Act through Gq which activates PLC -> formation IP3 and DAG -> increased cytosolic Ca2+ -> contraction -> - vasoconstriction -> inc in diastolic and systolic BP - small dec in cardiac output - increase in circulation time
phenylephrine fx
decongestion fo mucous membranes (vasoconstriction to reduce nasal fluid in hay fever, sinusitis, rhinitis) treatment of hypotension w/o overt cardiostimulation
phenylephrine side effeects
- can have B effects at high doses (bradycardia) - CNS effects (excitement, restlessness, headache) - arrhythmia - hypertension
prazosin trade name
minipress
prazosin drug class
alpha adrenergic antagonist
prazosin mechanism of action
competitive inhibition of a1-adrenergic receptors -> no stim PLC via Gq so no formation IP3 and DAG so no increase in cytosolic Ca2+ so no contraction -> decrease BP and peripheral vascular resistance; has dilatory effects on arterial and venous side also decreases RA pressure; CO increased in patients with CHF
prazosin fx
- treatment CHF (reduce peripheral resistance w/ decrease after load) - treatment of hypertension - pheochromocytoma (catecholamine secreting tumor of adrenal medulla; overcome hypertensive attacks and counteract effects of manipulation of tumor during sx removal usually combine with B blocker) - cardiovascular shock (overcome compensatory vasoconstriction -> decreased tissue perfusion must use in conjunction with adequate fluid therapy) not in notes: - reduce symp tone when treating uretheral obstruction
prazosin side effect
- hypotension - CNS (lethargy, dizziness ect.), GI effects
propranolol trade name
inderal
propranolol drug class
beta adrenergic antagonist
propranolol mechanism of action
blocks B1 and B2 receptors in myocardium, bronchi, and vascular smooth m muscle - B1 block -> dec HR dec force contraction and dec AV nodal conduction velocity and dec renin secretion - B2 block -> constriction smooth muscle (vascular, bronchial ect.)
propranolol fx
-anti arrhythmic agent (supra ventricular and ventricular arrhythmias, v useful w/ v fib) - photochromocytoma (use to manage tachycardia and arrhythmias during sx) - control symptoms hyperthyroidism - treat CHF (not severe or acute) - short term treatment of hypertension
propranolol side effects
- bradycardia - lethargy - depression - impaired AV conduction - CHF or worsening HF - hypotension - syncope - diarrhea - hypoglycemia - bronchoconstriction
Metoprolol trade name
lopressor
metoprolol drug class
beta 1 adrenergic antagonist
metoprolol mechanism of action
B1 adrenergic antagonist can block B2 at high dose - negative inotropic and chronotropic actions
metoprolol fx
- cardiac arrhythmias (supra ventricular and ventricular) - v fib (type of arrhythmia) - Pheochromatocytoma (manage tachycardia and arrhythmias during sx along w/ a blocker) - Hyperthryroidism - Congestive heart failure (milld to moderate only)
metoprolol side effects
- bradycardia - lethargy - depression - impaired AV conduction - CHF - worsening heart failure - hypotension - hypoglycemia - bronchoconstriction - syncope - D+
atropine trade name
atropine
atropine drug class
muscarinic antagonist
atropine mechanism of action
-inhibits acetylcholine and other cholinergic stimulants at postganglionic parasympathetic neuroeffector sites - high dose can block nicotinic receptors at autonomic ganglia and NMJ
atropine side effects
- dry mount - increased viscosity of secretions - dysphagia - constipation - V+ - thirst - urinary retention or hesitancy - CNS effects (stimulation, drowsiness, ataxia, seizures, respiratory depression) - Opthamic effects (blurred vision, pupil dilation, cycloplegia, photophobia) - Cardiovascular effects (sinus tachycardia, increased myocardial work, O2 consumption, bradycardia, hypertension, hypotension, arrhythmias, circulatory failure)
atropine function
- antidote for organophosphate intoxication - preanesthetic prevent or reduce secretions of respiratory tract - treat sinus bradycardia, sinoatrial arrest, incomplete AV block - differentiate vagally-mediated bradycardia for other causes - antidote for OD cholinergic agents
