Drug TherapyDrug Therapy Heart Failure Heart Failure

by Pat Woodbery, MSN, ARNPby Pat Woodbery, MSN, ARNP

Heart FailureHeart Failure

Congestive Heart Failure (CHF)Congestive Heart Failure (CHF)– Heart cannot pump enough blood.Heart cannot pump enough blood.

Impaired myocardial contractionImpaired myocardial contraction Impaired filling of ventriclesImpaired filling of ventricles

When CHF occurs When CHF occurs Compensatory MechanismsCompensatory Mechanisms

Increased catacolaminesIncreased catacolamines Increased force of contractionIncreased force of contraction Increase HRIncrease HR Increase vasoconstrictionIncrease vasoconstriction

Heart FunctionHeart Function

AFTERLOAD: Force against AFTERLOAD: Force against which the ventricles eject which the ventricles eject bloodblood

PRELOAD: Blood return to PRELOAD: Blood return to the heart (Diastolic filling the heart (Diastolic filling pressure)pressure)

WORKLOAD: Actual ejection WORKLOAD: Actual ejection

Digoxin (Lanoxin)Digoxin (Lanoxin)

Cardiotonic Effect Cardiotonic Effect – Improvement of cardiac pumpingImprovement of cardiac pumping– Increased emptying of ventriclesIncreased emptying of ventricles– = Increased CARDIAC OUTPUT== Increased CARDIAC OUTPUT=

How Does Digoxin Work?How Does Digoxin Work?

Inhibits cardiac muscle enzymeInhibits cardiac muscle enzyme Na,K-adenosine triphosphataseNa,K-adenosine triphosphatase– Decreased movement of Na out of the myocardial Decreased movement of Na out of the myocardial

cells after contractioncells after contraction– Calcium enters the cell in exchange for sodiumCalcium enters the cell in exchange for sodium– This stimulates more Calcium = activated This stimulates more Calcium = activated

contractile proteinscontractile proteins– Increased myocardial contractilityIncreased myocardial contractility

How Does Digoxin Work?How Does Digoxin Work?

Slows the rate of ventricular Slows the rate of ventricular contractionscontractions– Depresses cardiac conduction Depresses cardiac conduction

tissuestissues– Depresses AV nodeDepresses AV node– Stimulates Vagus NerveStimulates Vagus Nerve

Indications for Use of Indications for Use of DIGOXINDIGOXIN

Heart FailureHeart Failure

Atrial FibrillationAtrial Fibrillation

Atrial FlutterAtrial Flutter

Administration of DigoxinAdministration of Digoxin

ORALORAL Onset 30 minutes to 2 hoursOnset 30 minutes to 2 hours Peak 6 hoursPeak 6 hours

Intravenous (IV)Intravenous (IV) Onset 10-30 minutesOnset 10-30 minutes Peak 1-5 hoursPeak 1-5 hours

DigitalizationDigitalization

Administration of an amount of Digoxin sufficient to Administration of an amount of Digoxin sufficient to produce therapeutic effectsproduce therapeutic effects

Digoxin ToxicityDigoxin Toxicity

Nonspecific Early SymptomsNonspecific Early Symptoms– Anorexia, nausea, confusionAnorexia, nausea, confusion

Signs and Symptoms of Heart DiseaseSigns and Symptoms of Heart Disease– Atrial FibrillationAtrial Fibrillation– Rapid Ventricular RateRapid Ventricular Rate

Rapid Ventricular ResponseRapid Ventricular Response

Diagnosis of Diagnosis of Digoxin ToxicityDigoxin Toxicity

Serum Drug LevelsSerum Drug Levels EKGEKG

Treatment of Treatment of DIGOXIN TOXICITYDIGOXIN TOXICITY

Discontinue DrugDiscontinue Drug

Treat Cardiac ArrhythmiasTreat Cardiac Arrhythmias

Digoxin immune fab (Digibind)Digoxin immune fab (Digibind)

Nursing ActionsNursing Actions

Check Dosing CAREFULLYCheck Dosing CAREFULLY Check Apical PulseCheck Apical Pulse Give with food or after mealsGive with food or after meals Inject slowly (over 5 minutes)Inject slowly (over 5 minutes)

Observe forObserve for Therapeutic Effects Therapeutic EffectsDecreasedDecreased IncreasedIncreased

DyspneaDyspnea Activity ToleranceActivity Tolerance

Heart RateHeart Rate Well BeingWell Being

CyanosisCyanosis

CoughCough

AnxietyAnxiety

EdemaEdema

Antianginal DrugsAntianginal Drugs

Angina PectorisAngina Pectoris

Clinical SyndromeClinical Syndrome

Episodes of Chest PainEpisodes of Chest Pain

Deficit in Myocardial OxygenDeficit in Myocardial Oxygen

Most often caused by Most often caused by atherosclerotic plaquesatherosclerotic plaques

Antianginal DrugsAntianginal Drugs

Decrease Myocardial Decrease Myocardial Demand for OxygenDemand for Oxygen

Increase Blood Supply Increase Blood Supply to Myocardiumto Myocardium

Organic NitratesOrganic NitratesNitroglycerine (Nitrostat SL)Nitroglycerine (Nitrostat SL)

1. Relax Smooth Muscle

2. Produce Vasodilation

3. Decrease Preload

4. Decrease Workload

5. Decrease Afterload

SublingualSublingual– Action 1-3 minutesAction 1-3 minutes– Duration 30-60 minutesDuration 30-60 minutes

Nitroglycerine Nitroglycerine

Client TeachingClient Teaching

Original ContainerOriginal Container Replace every 6 Replace every 6

monthsmonths Headache and Headache and

DizzinessDizziness Avoid OTCAvoid OTC Avoid AlcoholAvoid Alcohol

How to Administer Nitroglycerine?How to Administer Nitroglycerine?

Under tongueUnder tongue Take at first sign of an attackTake at first sign of an attack If no relief in 5 minutes take a If no relief in 5 minutes take a

second SL tabletsecond SL tablet If no relief in 5 minutes take a If no relief in 5 minutes take a

third SL tabletthird SL tablet

Nursing ActionsNursing Actions

Check Blood Pressure and Check Blood Pressure and Heart Rate BEFORE each Heart Rate BEFORE each dosedose

Observe for relief of chest Observe for relief of chest painpain

Observe for hypotension, Observe for hypotension, dizziness, tachycardia, dizziness, tachycardia, headacheheadache

Test QuestionsTest Questions