Cardiac Medications: Digoxin & Inotropes

Digitalis Toxicity Risk Factors

• Elderly clients are at higher risk for digitalis toxicity.

Digoxin Administration Contraindications

• Digoxin should not be administered if the heart rate is below 60 bpm.
• Monitor apical heart rate during digoxin therapy; hold if pulse is below 60 or above 120 bpm.

Inotropic Medications

• Inotropic medications increase the force of contraction.

Digoxin Administration Precautions

• Monitoring potassium levels is crucial due to the increased risk of digoxin toxicity in hypokalemia.

Digoxin Therapeutic Drug Level

• The therapeutic drug level for digoxin is 0.5-2.0 ng/mg.

Digoxin Toxicity Signs

• Blurred vision or halos indicates digoxin toxicity.

Amrinone (Inocor) Mechanism of Action

• Amrinone (Inocor) is a short-term CHF therapy that increases stroke volume and heart rate.
• It also decreases peripheral vascular resistance due to its vasodilating effect.

Milrinone (Primacor) Administration

• Review the medication regimen to check for IV furosemide (Lasix) because milrinone (Primacor) is incompatible with it.

Ventricular Ectopy Treatment

• Lidocaine (Xylocaine) is the first-line drug for treating ventricular ectopy.

Class IA Antiarrhythmic Agents Effects

• Class IA antiarrhythmic agents have minimal effect on the SA node.

Severe Hematologic Disorders

• Procainamide (Pronestyl) can cause severe hematologic disorders.

Antiarrhythmic Agents Indications

• Frequent ventricular ectopy indicates the necessity of an antiarrhythmic.

Antiarrhythmic Agents Assessment

• When administering an antiarrhythmic agent, ECG is the most important parameter to evaluate.

Antiarrhythmic Agent Effectiveness

• Drug levels indicate if there is an adequate amount of drug in the blood to prevent arrhythmias.

Critical Care Antiarrhythmic Agents

• Bretylium (Bretylol) should be used only when the client can be closely monitored.

Most Toxic Antiarrhythmic Agent

• Amiodarone (Cordarone) is the most toxic antiarrhythmic agent.

Epinephrine Actions

• Epinephrine treats cardiac arrest and status asthmaticus by bronchodilation and increasing heart rate, contractility, and conduction.
• Bronchodilation results from stimulated beta receptors, and cardiac effects result from the stimulation of ß1 receptors.

Norepinephrine (Levophed) Assessment

• After administering norepinephrine (Levophed), assess the color and temperature of toes and fingers to ensure circulation.

Norepinephrine (Levophed) Contraindications

• Norepinephrine (Levophed) is contraindicated in hypovolemic shock.

Dopamine (Intropin) Administration

• Dopamine (Intropin) cannot be directly mixed with solutions containing bicarbonate or aminophylline.
• The drug's action varies according to the dose.

Dobutamine (Dobutrex) Indications

• Dobutamine (Dobutrex) improves cardiac output, but it is not indicated for arrhythmias.

Conduction Defect Adverse Effects

• Conduction defects are most likely to be an adverse effect of verapamil.
• Verapamil has the strongest chronotropic effect causing a delay in conduction at the SA and AV nodes.

Calcium Channel Blockers

• Nifedipine has the most potent peripheral smooth muscle dilator effect of all the calcium channel blockers.

Adverse Reactions

• Hypotension is prevalent in volume-depleted elderly clients, because of their increased sensitivity to the effects of diuretics

Cerebral Vasospasm

• Nimodipine is used to counteract or prevent cerebral vasospasm.

Blood Pressure Reduction

• Calcium channel blockers decrease peripheral vascular resistance, reducing blood pressure.

Beta Blockers Assessment

• Pulmonary function tests should not be included in the routine assessment, unless there is a history of pulmonary disease.

Beta Blockers Monitoring

• Blood glucose should be routinely monitored in clients taking ß blockers due to their influence on glucose metabolism.

Beta Blockers Mechanism

• Beta-blocking agents block catecholamine receptor sites.

Beta Blockers Contraindications

• Beta blockers should be avoided in bronchoconstriction.

Action of Nitrates

• Nitrates cause smooth muscle relaxation and vasodilation.

Results of Nitrate Administration

• Nitrate administration results in decreased myocardial oxygen demand, reduced preload, and decreased left ventricular end-diastolic volume.

Long-acting Nitrate Example

• Isosorbide PO is an example of a long-acting nitrate.

Nitrates & Acute MI

• Early nitrate administration to acute MI clients reduces mortality.

Nitrate Administration Teaching

• Instruct clients to change positions slowly to avoid orthostatic hypotension.

ACE Inhibitors Physiologic Effects

• ACEs participate in the renin-angiotensin-aldosterone system to promote sodium and water retention

ACE Inhibitor Administration

• Monitor for hypotension before ambulating the client after ACE inhibitor administration.

ACE Inhibitor Patient Teaching

• It isimportant to understand the risk of hyperkalemia and which foods to eat in moderation.
• Be aware that taking medications with food will decrease therapeutic effects of ACE inhibitors.
• Avoid excessive amounts of caffeine.
• Also avoid salt substitutes that are high in potassium to decrease the risk of hyperkalemia.

ACE Inhibitor Response

• ACE inhibitors interrupt the renin-angiotensin-aldosterone mechanism, thereby increasing sodium excretion and potassium reabsorption.

Vasodilators

• Vasodilators relax smooth muscles and are used to treat hypertension.

Vasodilators Use

• Vasodilators are mainly used to treat hypertension and not used to treat diabetes, atrial fibrillation, or hypotension.

Vasodilators for Vascular Obstructive Disease

• Pentoxifylline (Trental), cyclandelate (Cyclan), and isoxsuprine (Vasodilan) treat peripheral or cerebral vascular obstructive disease.

Vasodilator Post TIA

• Nitroprusside (Nitropress) is commonly used for transient ischemic attacks.

Peripheral Vascular Disease Education

• Health education for clients with peripheral vascular disease should include smoking cessation, proper rest and activity balance, and proper foot care.

Aldosterone Antagonists Action

• Aldosterone antagonists inhibit the exchange of sodium for potassium.

Furosemide (Lasix) Side Effects

• A potential side effect of IV furosemide (Lasix) is hearing loss.

Mannitol (Osmitrol) Monitoring

• Monitor for fluid volume excess when administering IV mannitol (Osmitrol).

Potassium-Sparing Diuretics

• All potassium-sparing diuretics are weak diuretics.

Diuretics Adverse Effects

• Elderly clients are more likely to experience adverse effects from treatment with diuretics.

Lipid-Lowering Agents Action

• Lipid-lowering agents aim to increase HDL.

Successful Lipid-Lowering Therapy

• For lipid-lowering agents to be successful, drug therapy must lower LDL.

Lipid-Lowering Agent Contraindications

• The most significant contraindication for therapy with lipid-lowering agents is liver disease.

Bile Acid Sequestrants Absorption

• Vitamin K may not be absorbed properly when giving bile acid sequestrants.

Lipid-Lowering Agents Side Effects

• Lovastatin (Mevacor) has the common side effect of constipation.

Parenteral Anticoagulants Mechanism

• Parenteral anticoagulants disrupt the conversion of prothrombin to thrombin.

SC Heparin Administration

• SC heparin should be administered in the abdominal fat.

Heparin Half-Life

• The half-life of heparin is 1 to 1.5 hours.

Heparin Overdose Antidote

• Protamine sulfate (Protamine) is used to stop bleeding associated with heparin overdose.

Warfarin (Coumadin) PT Extension

• During warfarin (Coumadin) administration, the initial extension of PT occurs within 8 to 12 hours after therapy begins.

Warfarin Instructions

• Avoid taking Ecotrin (Enteric coated aspirin) for headaches due to the risk of bleeding.
• Activated partial thromboplastin time (aPTT) is prescribed to monitor the therapeutic effect of heparin.

Heparin Therapeutic Effect

• An activated partial thromboplastin time of 60 seconds indicates that the client is receiving the therapeutic effect.

Protamine Sulfate

• Protamine sulfate reverses the anticoagulant effects of heparin.

Streptokinase (Streptase)

• Stop the infusion and notify the physician if the client on streptokinase complains of difficulty breathing, itchiness, and nausea.

Streptokinase Contraindications

• Streptokinase is contraindicated if blood pressure is 185/110 mm Hg.

Bleeding Reversal

• Bleeding can be reversed with the use of aminocaproic acid as an antidote for streptokinase.

Antiplatelet Medications

• Antiplatelet medications cannot be used with anticoagulants.

Procainamide (Procanbid)

• Check the blood pressure and heart rate if the client suddenly complains of nausea and drowsiness, as they are experiencing signs of Procainamide toxicity.

Alteplase (Activase, tPA)

• While on Alteplase (Activase, tPA) therapy, the nurse plans to prioritize observation for signs of bleeding.

Digoxin Toxicity Rate

• The therapeutic level of digoxin is 0.5-2 ng/ml.

Carvedilol (Coreg CR)

• When taking Carvedilol (Coreg CR), complaints of dyspnea is a sign of bronchospasm which is one of the serious complication of beta blockers.

Metoprolol Interactions

• "This medication may mask some of the symptoms of hypoglycemia such as tremor, palpitation, and rapid heartbeat"

Metolazone (Zaroxolyn) & Lab Results

• Hypokalemia and hyperglycemia are related to the administration of Metolazone (Zaroxolyn).

Torsemide (Demadex) Priority Assessment

• Monitor blood pressure after the initiation of Torsemide (Demadex).

Cholestyramine (Questran) Instructions

• "I will continue taking nicotinic acid as part of the treatment" indicates the need for further instruction.

Nicotinic Acid Instructions

• "I should take aspirin 30 minutes before nicotinic acid"

Digoxin (Lanoxin) Side Effects

• Tremors are not a side effect associated with digoxine.

Bumetanide (Bumex) Concern

• The is a concern for a sulfa allergy related to the administration of Bumetanide (Bumex).

Acute MI Immediate Action

• If the client still complains of chest pain with a pain scale of 2/10 an immediate action needs to be taken.