Week 5 Cardiovascular Agents Part III Flashcards
What is heart failure?
It is a Chronic illness with acute decompensation. The eart muscle (myocardium) weakens, enlarges and loses its ability to pump blood through the heart and into the systemic circulation.
What are some causes of heart failure?(6)
- Chronic hypertension
- Myocardial infarction
- Coronary artery disease
- Valvular heart disease
- Congenital heart disease
- Aging heart
ACC/AHA Stages of Heart Failure: the characteristics of stage 1 (or A) are:
High risk for HF without symptoms or structural disease
ACC/AHA Stages of Heart Failure: the characteristics of stage 2 (or B) are:
Some levels of cardiac changes (e.g., decrease ejection fraction without symptoms of heart failure)
ACC/AHA Stages of Heart Failure: the characteristics of stage 3 (or C) are:
Structural heart disease with symptoms of HF (e.g., fatigue, SOB, edema, decreased physical activity)
ACC/AHA Stages of Heart Failure: the characteristics of stage 4 (or D) are:
Severe structural heart disease and marked symptoms of HF at rest
Heart Failure: ____ sides of the heart can fail
Both
Heart failure (HF) is not a ___ but a ___
disease, “syndrome”
Heart failure is preventable. if there is a 30-day re-admission = _____ ___
not paid
What happens when the left side of heart fail?
Excessive amounts of blood backup into lung tissue
What happens when the right side of heart fail?
Blood backed up into peripheral tissues
what is the Heart Failure Biomarker?
Brain Natriuretic Peptide - BNP
What is Brain Natriuretic Peptide (BNP)?
neurohormone released from the ventricular cells in response to increased cardiac filling pressures.
Plasma measurements of BNP have been shown to reflect __ ___, to predict ___ at admission and discharge, and to serve as a __ ___.
volume status
risk
treatment guide
What is the normal range of BNP?
less than 100 pg/ml (CHF improbable)
What is indicated if BNP reaches Level 100-400 pg/ml?
clinical suspicion of CHF or past history of CHF (HF 75% probable)
What does a BNP Levels >400 pg/ml indicate?
CHF is 95% probable
What does a BNP’s Values greater than 500 pg/mL prove?
it proves accurate in supporting the diagnosis of ADHF (acute decompensated HF)
What’s the normal ejection fraction (EF)?
55-70%
What’s HFpEF?
HF with preserved ejection fraction. Left ventricular ejection fraction (LVEF) is normal (formerly diastolic HF)
What’s HFNEF?
HF with a normal ejection fraction. Same as HFpEF.
What’s HFREF?
HF with reduced ejection fraction
On average, EF decreased by ___ over__ years (p
5.8% 5 older 39% 50% 5
What are the Pharmacologic therapies of Heart Failure? (6)
- Cardiac muscle contraction efficiency - Cardiac Glycosides (inotropes)
- Cardiac muscle contraction efficiency - Phosphodiesterase Inhibitors
- Decrease cardiac stress (vasodilators)
- Inhibit renin-angiotensin system (ACE inhibitors or ARBs)
- Inhibit sympathetic nervous system (Beta Blockers)
- Reduce volume overload (Diuretics)
- –May not decrease mortality but provides symptomatic relief
What are the Non-pharmacologic treatments of heart failure? (7)
Limit salt, improve potassium intake Limit or avoid alcohol intake Smoking cessation Decrease saturated fat intake Perform mild exercise as possible Other Interventions Flu and pneumonia vaccination Weight loss
Effects and Terminologies: what is inotropic effect?
myocardial contraction (digitalis)
Effects and Terminologies: what is chronotropic effect?
heart rate (beta blockers)
Effects and Terminologies: wha tis dromotropic?
conduction of heart cells (anti-arrhythmias)
Drugs may have ___ properties/effects
multiple
What is Cardiac Glycosides?
It is derived from foxglove plant
What is the mechanism of action of cardiac glycosides?
Inhibit Na+ - K+ pump → increased intracellular Ca++ during depolarization.
What is the indications of cardiac glycosides?
CHF, atrial flutter/fibrillation and paroxysmal atrial tachycardia
what is the prototype drug of cardiac glycosides?
digoxin (lanoxin)
What other drugs can the nurse use if digoxin is not effective?
Calcium channel blocker: verapamil (Calan), Coumadin
How Cardiac Glycosides Work? (4)
Positive (+) inotropic effect
Negative (-) chronotropic effect
Negative (-) dromotropic effect
↑ stroke volume
what is Positive (+) inotropic effect?
↑ myocardial contractility
what is Negative (-) chronotropic effect?
↓ heart rate
What is Negative (-) dromotropic effect?
↓ AV node conduction
How Cardiac Glycosides Work? (4)
- Increases Cardiac Output
- Improves blood flow to kidneys & periphery
- Decreases peripheral and lung fluid retention
- Increases fluid excretion
What is Digoxin (Lanoxin)’s dosage for adults?
orally:
0.5 – 1 mg initially in 2 divided doses (digitalization)
Then 0.125 - 0.5 mg/day (maintenance)
What is Digoxin (Lanoxin)’s IV dosage for adults?
Same as PO dose, given over 5 min
What is Digoxin (Lanoxin)’s dosage for elderly?
Elderly: 0.125 mg/day
What is Digoxin (Lanoxin)’s dosage for children?
Pediatric doses usually ordered in mcg in elixir form
Digoxin: Pharmacokinetics
what is the absorption percentage for oral digoxin and liquid digoxin?
Oral: tab 60-70%, liquid 90%
Digoxin: Pharmacokinetics
What is digoxin’s distribution? hint: protein binding
Protein binding 20 - 30%
Digoxin: Pharmacokinetics
what is digoxin’s metabolism rate? hint: half life
t ½ 30-40hrs
Digoxin: Pharmacokinetics
How is digoxin excreted?
70% urine & 30% by liver metabolism
Digoxin has a higher risk for toxicity in what patients?
renal
Digoxin: Drug Interactions
what 3 meds can increase serum digoxin levels? and what type of drugs are they?
Quinidine, verapamil, flecainide (drug receptor site competition; enzyme pathways)
Digoxin: Drug Interactions
what process and drug can decrease serum digoxin levels?
Via decreased absorption with antacids
Digoxin: Drug Interactions
what 2 drugs can increased risk for digoxin toxicity? how?
Thiazide & loop diuretics
–due to hypo K
Digoxin: Drug Interactions
Explain the interaction between electrolytes and the digitalis effects. How do they affect each other?
Hypokalemia, hypomagnesemia, hypercalcemia can increase digitalis toxicity. ↓ of these electrolytes = ↑ digitalis effects
What herbs can affect digoxin?(6)
- ginseng
- st. john’s wort
- hawthorn
- aloe
- ma-huang
- licorice
what is ginseng’s affect on digoxin?
falsely elevates digoxin level
what is st. john’s wort’s affect on digoxin?
↓absorption, ↓ serum level
what is hawthorn’s affect on digoxin?
↑effect of dig
what is aloe’s affect on digoxin?
↑potassium loss
what is ma-huang’s affect on digoxin?
↑risk of dig toxic
what is licorice’s affect on digoxin?
potentiates effect of dig
what are some symptoms of digoxin toxicity?
Therapeutic serum level is 0.5 to 2.0 ng/ml
-Bradycardia (HR
How will elderly respond to digoxin toxicity?
> prone
= Beers Criteria
what should the nurse assess on a pt taking digoxin? (4)
- check Serum K+ level
Low K+ enhances action of digoxin - Baseline apical pulse rate for one full minute
- Check for signs & symptoms digoxin toxicity
- Check BUN and Creatinine
What is an antidote for digitalis toxicity?
digoxin immune fab (digibind)
Inotropic Agents: Dopamine
what is dopamine’s mechanism of action?
sympathomimetic, ↑ BP and HR, causes renal and sphlanchnic arteriole dilatation = increase urine output. Positive Inotropic
Inotropic Agents: Dopamine
what is dopamine used for?
acute heart failure – ICU setting, symptomatic bradycardia, shock
Inotropic Agents: Dopamine
what caution should the nurse take before giving dopamine?
correct hypovolemia first with fluids
Inotropic Agents: Dopamine
what are the 2 side effects of dopamine?
tachyarrhythmia, hypertension
Inotropic Agents: Dobutamine
what is the mechanism of action of dobutamine?
sympathomimetic, with slight preference for beta 1 receptor. ↑ heart contractility without much change in rate. Positive Inotropic.
Inotropic Agents: Dobutamine
what are the uses of dobutamine?
acute heart failure – ICU setting
Inotropic Agents: Dobutamine
what caution should the nurse take before giving dobutamine? (2)
correct hypovolemia first, check liver disease
Inotropic Agents: Dobutamine
what are the side effects of dobutamine?
tachyarrhythmia, ectopic beats, hypotension
what is agonist?
a drug which has affinity for the cellular receptors of another drug or natural substance and which produces a physiological effect.
what are the effects of Alpha and Beta Adrenergic Agonists on alpha 1 adrenoceptors? (5)
- vasoconstriction
- increased peripheral resistance
- increased bp
- mydriasis
- increased closure of internal sphincter of the bladder
what are the effects of Alpha and Beta Adrenergic Agonists on alpha 2 adrenoceptors? (3)
- inhibition of norepinephrine release
- inhibition of acetylcholine release
- inhibition of insulin release
what are the effects of Alpha and Beta Adrenergic Agonists on Beta 1 adrenoceptors? (4)
- tachycardia
- increased lipolysis
- increased myocardial contractility
- increased release release of renin
what are the effects of Alpha and Beta Adrenergic Agonists on Beta 2 adrenoceptors? (6)
- vasodilation of skeletal muscles
- slightly decreased peripheral resistance
- bronchodilation
- increased muscle and liver glycogenolysis
- increased release of glycogen
- relaxed uterine smooth muscle
what is the mechanism of action of Phosphodiesterase Inhibitors (PIs)?
inhibit the enzyme phosphodiesterase which promotes vasodilation and a + inotropic response
what is Phosphodiesterase Inhibitors (PIs) used for?
acute HF
What should the nurse be caution about while giving Phosphodiesterase Inhibitors (PIs)?
Administered IV for no longer than 48 to 72 hours to avoid severe cardiac dysrhythmias
What is the most common Phosphodiesterase Inhibitors (PIs)?
Milrinone (Primicor)
What other vasodilator agents can be used for Heart Failure ? (5)
- Angiotensin-converting enzyme (ACE) inhibitors
- Angiotensin II receptor blockers (ARB)
- Beta blockers
- Atrial Natriuretic Peptide
- Nitroglycerine
What other diuretic agents can be used for Heart Failure? (3)
Thiazides, furosemide, spironolactone (Aldactone)
how does vasodilators help HF? (4)
- Decrease venous blood return to heart
- Decrease preload (volume)
- Decrease oxygen demand
- Arterial dilators
- -Reduce cardiac afterload (vascular resistance)
- -Improve renal perfusion (diuresis)
- -Improve circulation to skeletal muscles
What is BiDil?
Combination of hydralazine (direct-acting smooth muscle relaxant ) and isosorbide dinitrate (a dilator to relieve angina)
BiDil: ___ ___ for treating ___, especially in ____ ____.
FDA approval
HF
African-Americans
Where is BiDil metabolized?
in the liver
What is the half-life of BiDil?
3 to 6 hours
BiDil has a drug interaction with what?
Phosphodiesterase Inhibitors
What can Angiotensin-Converting Enzyme (ACE) inhibitors do? (5)
Dilates venules and arterioles Moderately decrease the release of aldosterone (antagonizes RAAS) Improves renal blood flow Decreases blood fluid volume (preload) Can increase serum potassium
Angiotensin II Receptor Blockers (ARB): Have been ___ in clients who cannot tolerate ___ ____
approved
ACE inhibitors
What are 2 examples of angiotensin II Receptor Blockers (ARB)?
Valsartan (Diovan) and candesartan (Atacand
what is an example of beta- blockers?
Carvedilol/Coreg (antioxidant protectant)
what is Carvedilol (Coreg)?
3rd generation Beta receptor antagonist
What 3 receptors can Carvedilol (Coreg) block?
Beta1, Beta2, and Alpha1 receptors
What can Carvedilol (Coreg) do? (2)
- Antioxidant protects against free radicals causing damage to nucleic acids, proteins, and lipids (linked to ca, atherosclerosis)
- Slows progression of CHF
What is another example of Beta Blockers?
Metoprolol (Lopressor)
What can Metoprolol (Lopressor) do? (4)
- Selective Beta1 blocker
- Beneficial effects in heart failure patients
- Improved ejection fraction, exercise tolerance, and quality of life
- May improve survival
What is an example of Atrial Natriuretic Peptide?
Nesiritide (Natrecor)
What are the 3 functions of Nesiritide (Natrecor) ?
- Inhibits antidiuretic hormone (ADH) by increasing urine sodium loss
- Promotes vasodilation, natriuresis, and diuresis
- Used for treatment of acute decompensated HF with dyspnea at rest, dyspnea with little physical exertion (stage 4 CHF?)
What are 2 examples of Diuretics?
Thiazides, Furosemide
What is Thiazides’ function on the kidney?
Inhibit active exchange of Cl-Na in the cortical diluting segment of the ascending loop of Henle
What is K-sparing’s function on the kidney?
Inhibit reabsorption of Na in thedistal convoluted and collecting tubule
What is loop diuretics’ function on the kidney?
Inhibit exchange of Cl-Na-K in the thick segment of the ascending loop of Henle.
what is the mechanism of action for Potassium-Sparing Diuretics?
Blocks production of aldosterone. Work primarily in the collecting duct renal tubules and late distal tubule. Promotes sodium and water excretion. Decreases myocardial fibrosis
–Cardioprotective effect of blocking aldosterone in the heart and blood vessels to promote cardiac remodeling
What can potassium -sparing diuretics lead to?
Can lead to hyperkalemia (normal K: 3.5 to 5.0 mEq/L)
what is the prototype med for potassium-sparing diuretics?
Spironolactone (Aldactone)
What should the nurse assess on a pt with HF? (3)
- baseline v/s, o2 sat, abg, electroyltes, LFT, CBC, weight, and urinary output.
- adl
- assess for edema–peripheral and pulmonary.
what are some nursing diagnoses for HF patients?
- impaired cardiac output
- risk for fluid volume abnormalities
- electrolyte imbalance
What are some goals (planning) for HF patients?
- client will be without dyspnea.
- client’s edema will decrease
- client’s serum chemistry levels will remain wnl.
What are some nursing interventions for HF patients?
- Monitor, V/S, Electrolytes, Daily wt & u/o, breathing
- Observe for s & s of electrolyte imbalance esp. hypokalemia (except K+ sparing)
- Muscle weakness, muscle cramps, dysrhythmias
- Observe for s & s of dehydration
what are some other diuretics used for miscellaneous conditions? (2)
- osmotic diuretics
2. carbonic anhydrase inhibitors
What is carbonic anhydrase inhibitors?
Carbonic anhydrase is an enzyme found in the proximal convoluted tubule in the kidney that helps maintain balance of hydrogen ion and bicarbonate in our bodies
what is the mechanism of action for carbonic anhydrase inhibitors?
inhibits action of carbonic anhydrase causing Na+, K+, & HCO3- excretion in proximal renal tubule
what are the uses for carbonic anhydrase inhibitors?
primarily used to ↓ intraocular pressure in open-angle (chronic) glaucoma. May be used to alkalinize urine such as in rhabdomyolysis
what is a prototype drug for carbonic anhydrase inhibitors?
acetazolamide (Diamox)
What are some side effects of carbonic anhydrase inhibitors?
- Fluid & electrolyte imbalances
- Metabolic acidosis
- N/V, anorexia
- Confusion
- Orthostatic hypotension
what are the 3 adverse reactions of carbonic anhydrase inhibitors?
hemolytic anemia
renal calculi
crystalluria
What is the mechanism of action of osmotic diuretics?
via osmotic effect to pull large amounts of fluid into the urine
what are osmotic diuretics used for? (2)
- Patients experiencing increased intracranial pressure, ↑ intraocular pressure
- To prevent kidney failure in patients receiving Cisplatin chemotherapy
what is the prototype med for osmotic diuretics?
Mannitol (Osmitrol)
How does Mannitol (Osmitrol) work?
as a sugar, pulls large amounts of fluid into the urine by osmotic pull of the sugar.
What are some side effects of mannitol?
Fluid and electrolyte imbalance
Pulmonary edema
Nausea
Vomiting
what are some contraindications of Mannitol? (2)
heart failure
renal failure
What is the administration method of mannitol?
Crystallization in vial if exposed to low temperature
Do not infuse if crystals are present