Cardiovascular Meds (Part 2) Flashcards
Vasodilators
- Hydralazine (apresoline)
- Nitroglycerine
- Isosorbide
Hydralazine (apresoline)
-MOA:
Selective dilation of arterioles, no effect on veins. HR increases
-Indications:
Essential hypertension, Hypertensive crisis (IV), Heart failure
-Adverse Effects:
reflex tachycardia, increased blood volume, lupus like syndrome
-Interactions:
combine with beta blocker to avoid reflex tachycardia; excessive hypotension.
-Oral and IV
Nitroglycerine
*Vasodilator (Anti-anginal)
-MOA:
Relaxes smooth muscle vasculature by unknown mech.; reduces preload, afterload, and myocardial O2 consumption (reducing myocardial workload)
-Therapeutic Action:
reduces BP, chest pain
-Indications: Chest pain (Angina)
Nitroglycerine Cont..
-Sublingual tablet:
Give three q5minutes
- Sublingual Spray
- May take before known chest pain producing activity
- Nitrocream (topical) measure in increments
-Transdermal Patch:
Apply to hairless area (Upper chest, back, arms, thighs) - routine basis to PREVENT chest pain
- Put patch on in morning and off in evening so tolerance does not develop
- Capsule SR: taken to prevent CP
- IV (TRIDIL*): Titrate IV drip according to BP (only in ICU)
Nitroglycerine Cont…………
-Side Effects:
HEADACHE, postural hypotension, facial flushing; circulatory collapse
-Drug Interactions:
Alcohol can worsen hypotension; IV nitro may antagonize heparin
-Nursing Implications:
Give analgesics for headache; take BP before administering and one hour after for transdermal preps
Clean area after removing patch; local burning not significant (new patch on a different area)
- Unrelieved pain after 15 minutes after SL is usually indicative of an MI
- Swimming and bathing with patch okay
Cardiac Glycosides include:
Digoxin (Digitalis)
Digoxin (Digitalis)
-MOA:
Increases force of myocardial contraction; Increases contractility (positive inotropic action), increases PR time from SA Node to AV node (possible effect of heart block)
-Therapeutic Action:
increases diuresis; used in atrial fibrillation, CHF
-Indications: Heart Failure (now 2nd line drug)
Digoxin (Digitalis) Cont….
-Adverse Effects:
Bradycardia, heart blocks, other dysrhythmias, visual disturbances, N&V, confusion, agitation
*VISUAL DISTURBENCES – yellow tine, halos (early signs of adverse effects)
-Interaction:
Multiple; anti-acids, antibiotics, amiodarone, verapamil, quinidine, etc.
-Nursing Implications:
take apical pulse ONE FULL MINUTE before giving, must be above ordered parameter, usually 50-60 in adults, 60-70 in children
- Digoxin levels should be checked daily when first started and periodically later; HYPOOOOOOKALEMIA increases risk of dig toxicity and is the most common reason for toxicity.
- DIGIBIND can be used to reverse effects of high levels (normal is 0.5 - 0.8 ng/ml); cost is $2-3,000 for a single dose
ACC/AHA Heart Failure Class
There is also a New York Association class
Stage A:
Patients at risk for heart failure who have not yet developed structural heart changes (i.e. those with diabetes, those with coronary disease without prior infarct)
Stage B:
Patients with structural heart disease (i.e. reduced ejection fraction, left ventricular hypertrophy, chamber enlargement) who have not yet developed symptoms of heart failure
Stage C:
Patients who have developed clinical heart failure
Stage D:
Patients with refractory heart failure requiring advanced intervention (i.e. biventricular pacemakers, left ventricular assist device, transplantation)
Usual Meds for Heart Failure:
Inotropics - Digoxin, Dopamine (sympathomimetic), Dobutamine
*Others drugs listed on PowerPoint that have already been mentioned
Dopamine
- is a catecholamine;
- activates Beta 1 receptors in the heart causing tachycardia (low dosage- 1-5 mcg/kg/min),
- dopamine receptors in the kidney (5-10 mcg/kg/min);
- alpha 1 receptors in the blood vessels at high dosages (>10 mcg/kg/min) which reduces cardiac output and can CAUSE ISCHEMIC FINGERS/TOES at high doses.
- Mainly used to increase low B/P
Dobutamine
- can increase myocardial contractility;
- does not activate alpha 1 receptors and is frequently preferred to dopamine.
- IV infusion
Anti-dysrhythmic drugs
Adenosine (cordarone)
Adenosine
STOPS THE HEART AND RESETS THE HEART***
-MOA:
decreases automaticity in the SA node and slows conduction through AV node. Inhibits cyclic AMP-induced calcium influx
-Indications:
Terminating SVT and Wolf-Parkinson White Syndrome
-A/E:
last briefly, sinus bradycardia, bronchoconstriction.
-Dosage:
Short half life 1.5 to 10 seconds, give IV bolus as close to the heart as possible.
STOPS THE HEART AND RESETS THE HEART***
Antiarrhythmic agent
Amiodarone (IV)
Amiodarone (IV)
-Class III: Potassium Channel Blockers (block repolarization)
-MOA:
Slows AV conduction and prolongs AV refractoriness
-Indications:
IV for initial treatment of recurrent Vfib and unstable Vtach.
A/E:
Severe hypotension, Bradycardia, may require pacemaker
Dosage:
very complex, but usually there is a maintenance infusion after high dosage for 1st 24 hours, of 0.5mg/min
Calcium Gluconate/Calcium Chloride
- Calcium chloride is a 10% IV solution, can be given undiluted but preferably give diluted 1-10 mg/kg
- CaCl is 3x more powerful than gluconate
-Indications:
Given based on serum calcium levels in hypocalcemia, magnesium toxicity, hyperkalemia (titrate dosage according to EKG changes), cardiac resuscitation (use AHA guidelines); calcium channel blocker toxicity, antidote for cardiac and respiratory depression of magnesium sulfate
-Contraindications:
In digitalized pts, hypercalcemia, ventricular fibrillation.
Usually post-cardiac surgery
HMG-CoA Reductase Inhibitors (Statins)
-Statin
- Atovastatin (Lipitor)
- Lovastatin (Mevacor)
- Niacin (Nicotinic Acid)
- Ezetimibe (Zetia)
Atovastatin (Lipitor) and Lovastatin (Mevacor)
-Actions:
Reduce LDL-C, Elevate HDL, may lower triglycerides but not prescribed for this
-S/E:
dyspepsia, cramps, flatulence, constipation and abdominal pain, usually mild and transient
-Adverse Effects:
MYOPATHY/RHABDOMYOLYSIS (muscle tissue broken down – CK will rise), results in renal damage (acute renal failure). Watch for high CK levels; hepatotoxicity (rare); rosuvastin (Crestor) has highest risk; Risk rises if other lipid, triglyceride agents are used. Dosage of crestor must be reduced in Asians
-Statin users MUST NOT EAT GRAPEFRUIT since the juice inhibits CYP3A4 isoenzyme (macrolide antibiotics, anti-fungals, HIV protease inhibitors, amiodorane, cyclosporin)
CATEGORY X
-Current LDL goal is 100 in heart disease and 70 in diabetes/cardiac
Niacin (Nicotinic acid)
-prototype drug- reduces LDL and TG levels, also can increase HDL levels, not shown to improve outcomes.
-A/E:
INTENSE flushing/ itching skin, gastric upset, NAUSEA AND VOMITING DIARRHEA.
(Can mitigate effect by taking 325 mg aspirin 30 minutes before the dose to prevent synthesis of prostaglandins).
Hepatotoxic, elevation of uric acid levels, hyperglycemia and gouty arthritis.
Ezetimibe (Zetia)
Cholesterol Blocker
-MOA:
inhibits dietary absorption of cholesterol secreted in the bile. Treatment reduces total cholesterol, LDL- C, triglycerides, slight rise in HDLs
-A/E:
generally well tolerated but some reports of rhabdo, hepatitis when combined with a statin and pancreatitis.
Fibric Acid Derivatives (Fibrates)
Gemfibrozil (Lopid)
also fenofibrate, fenofibric acid
Gemfibrozil
- Decreases VLDL’s, thereby lowering triglyceride levels. Increases HDL’s, no effect on LDL-C
- Treatment usually limited to those in whom dietary restriction of saturated fats fails
-A/E:
Gall stones, statin induced myopathy, hepatotoxicity
-Interactions:
displaces warfarin from albumin, increasing anti-coagulation; should not be given with a statin
