antidysrhythmic and antihypertensive agents

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Antidysrhythmic and Antihypertensive Agents. NURS 1950 Pharmacology Nancy Pares, RN, MSN. Objective 1: Define the term ‘ectopic site’. Heart beat arises outside the sinoatrial (SA) node Terms: Inotropic Chromotropic Domotropic. Objective 2: Define the terms. Arrhythmia or dysrhythmia - PowerPoint PPT Presentation

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  • NURS 1950 Pharmacology

    Nancy Pares, RN, MSN

  • Heart beat arises outside the sinoatrial (SA) nodeTerms:Inotropic

    Chromotropic

    Domotropic

  • Arrhythmia or dysrhythmia

    Variation of normal rhythm-usually associated with cardiac An electrical activity initiated by a spontaneous discharge

  • Decrease the automaticity of the cardiac tissues distant from the sinoatrial node.Alter the rate of conduction thru the heartAlter the refractory period between consecutive contractions.

  • Classed according to actionClass I: myocardial depressents-inhibit sodium ion movement preventing depolorizationIa: prolongs electrical stimulation (in cell)prolongs refractory time between impulses delays repolarization

    Ib: shortens the duration of the e-stimulation and the time between impulsesaccelerates repolerization

    Ic: most potent-slows conduction rate through atria and ventriclesno effect on repolorization

  • Class II: beta-andrenergic blocking agents-block sympathetic stimulation (slows conduction and decreases HRClass III: slows the rate of electrical conduction and prolongs refractory time-potassium channel blocking

  • Class IV:blocks calcium ion flow-prolongs elec stimulation and slows AV node conductionMisc: Adenosine and Digoxin: not related to any other agents

  • Objective 5: List the side effects of antirrhythmics

  • Includes:Disopramide phosphate (Norpace)Procainamide HCL (Pronestyl)Quinidine gluconate (Duraquin)Quinidine polygluconate (Cardioquin)

    Prototype: Procainamide (Pronestyl)

  • -derived from the cinchona bark-cardiac depressant effects: reduces excitability of the cardiac muscle, prolongs refractory period between consecutive contractionsAllows the sinoatrial node to take over

  • Used for atrial tachycardia, flutter and fibrillation.

    Side effects severe: 1/3 of clients must d/c use

  • S/E:GI distressCV disordersRashes, respiratory arrest, hemolytic anemia, agranulocytosisHypersensitivityCinchonism: tinnitus, nausea, HA, dizzinessimpaired vision, vertigo

  • Nursing Implications:Can reduce problems if nurse:Avoid use in CHF patientsMonitor digitalis levels (if on digitalis)Monitor potossium (K+) levelsMonitor sodium (Na+) levels

  • Routes:Oral with mealsParenteral: give slowly

  • Uses:ventricular arrhythmias (best), atrial fibrillation(helpful), paroxysmal atrial tachycardia (PAT)S/E: GI distress, ventricular tachy, hypotension and hypersensitivityAllergy most likely if allergic to caine drugs (related to local anesthetics)Can cause agranulocytosis: lupus like syndrome

  • S/E: hypotension, tachyarrythmias, anticholinergic effects

    Has lower incidence of adverse effects than quinidine or procainamide

    Oral dosing

  • Lidocaine (Xylocaine)Mexiletine (Mexitil)Phenytoin (Dilantin)Tocainide (Tonocard)

  • Use:Preventricular contractions (PVC), cardiac glycoside-induced tachyarrhythmias, cardioversion

    Action: very rapid onset (IV), short actingShortens the duration of elec stimGives precise control of cardiac status

  • S/E/Route:Excessive decrease in cardiac electrical conductivity Hypotension, bradycardia, dizziness; CNS effectsHypermetabolism (malignant hyperthermia ineffective if given orally (metabolized in liver)

  • Nursing Interventions:Continuous EKG

    Look at bottle before giving-should not contain preservatives or epinephrine

  • -standard classification is neuroleptic, but used for arrythmias caused by cardiac glycoside intoxicationAction: decreases automaticity of cardiac muscle, increases rate of conduction of the cardiac electrical impulses

  • S/E/ Route:Neurological disturbances: peripheral neuropathy, diplopia, ataxia, vertigo, drowsiness, confusionGI disturbancesSkin rash

  • Similar to lidocaineNursing Interventions:Given orally onlyMonitor EKGClient teaching: s/e and when to call MDS/E:Dizziness, nausea, parethesia, numbness, restlessness, tremor, GI distress, blood dyscrasiasShould not be used in 2nd or 3rd degree AV block without a pacemaker

  • Action: similar to lidocaineUse: ventricular arrhythmiasS/E/route:N/V, heartburn, dizziness, tremor, impaired coordinationGiven orally

  • Flecainide (Tambocor)

    Encainide (Enkaid)

    Rythmol

  • Action: local anestheticUse: ventricular arrhythmiasS/E/route:Can cause new or worsen arrhythmiasHigh degree of negative inotropyDizziness, visual disturbances, HA, nausea, fatigue, chest pain

  • Local anesthetic, membrane stabalizing, some beta blocking effectUse: life threatening ventricular arrhythmiasS/E: may cause new or worsen existing arrhythmias, dizziness, GI disturbances, may see 1st degree AV blockNursing Interventions: monitor with EKGContraindications: uncontrolled CHF, brady, bronchospasm, severe hypotension

  • Acebutolol (Sectral)Esmolol (Brevibloc)Propranolol (Inderal)Action:Inhibits cardiac response to sympathetic nerve stimulation by blocking the beta receptors; reduces heart rate, systolic BP and cardiac output.

  • Use: Ventricular arrhythmiasSinus tachycardiaParoxysmal atrial tachycardia (PAT)Premature ventricular contractions (PVC)Tachycardia associated with atrial flutter,or fibrillation

  • S/E:What would we expect to see?Slow HR, orthostatic hypotension, SOB, painful urination, wt gain > 2 lbs/day, insomnia, drowsiness, confusionMask the signs of hypoglycemiaNursing Interventions:Take pulse and report below 50, rise slowly, report symptoms, diabetics monitor BS closely

  • Amiodarone (Cordarone)

    Dofetilidide (Tikosyn)

    Sotalol (Betaspace)

  • Action:Prolongs the action potential of the atrial and ventricular tissuesAntagonizes (non competitive) the alpha and beta receptors causing vasodilationUse:Life threatening arrythmias non responsive to other agents

  • S/E/Route:Fatigue, tremors, sleep disturbances, numbness, ataxia, confusion, exertional dyspnea, non-productive cough, pleuritic chest pain, photosensitivitys/e often cause clients to d/c use> 400mg/day cause problemsGiven oral or IV

  • Nursing interventions:Loading dose is neededWatch monitor for new arrhythmiasDose adjustment is difficultMonitor/teach about post treatment arrhythmiasWear sunscreen

  • Action/Use: slows conduction through the AV node causing relaxation of the coronary and peripheral vesselsDysrhythmiasS/E:HA, dizziness, lower extremity edema, increases digoxin and quinidine levels

  • Nursing interventions:Do not crush or chew extended release tabletsUse with caution with other CV agents: digoxin, beta adrenergic blockersMonitor for partial or complete heart block, heart failure

  • Adenosine (Adenocard)

    Digoxin (Lanoxin)

    Ibutilide ( Corvert)

  • Action/Use:Strong depressant effect on SA and AV nodes-slowing conductionTreatment of paroxysmal supraventricular tachycardia (PST)Physiologic roles: energy transfer, prostoglandin release, inhibits platelet aggregation, coronary vasodilation, suppresses heart rate

  • S/EFlushing, SOB, chest pressure, nausea, HA, dizziness, peripheral edema, anxietyHalf life is 10 secondss/e are not lasting

  • Give meds on scheduled timeAssess 6 cardinal signs of CV diseaseChest pain, dyspnea, edema, fatigue, syncope, palpitations (C-D-E-F-S-P)Lab tests: CV markers (enzymes)Physical assessment of client: include EKG readings

  • Be prepared for emergency careO2 as neededAssist with ADLsClient educationLifestyleMedicationsReport s/e and adverse effects

  • Also called idiopathic

    essentially no known cause

  • Cardiac outputIncrease cardiac output=increased BPPeripheral vascular resistance (PVR)Lumen inside vessels will constrict and dilate which determines PVRTotal Blood volume (see diagram in Adams)

  • Carbonic anhydrase inhibitorsRarely used for hypertensionThiazidesLoop diureticsPotassium sparingUsed in combination therapy with thiazide or loop diuretic

  • Deplete blood volumeHelp excrete sodiumDilate peripheral ateriolesSpecific action unknownOften used in combinationPotentiates activity of other antihypertensivesCheap and effective

  • Thiazides:Most effective if creatinine clearance >30Most commonly used: HydrochlorothiazideLoop diureticsUsed when creatinine clearance
  • Potassium sparingContraindicated with renal disease, pregnancy, gout or kidney stonesNursing interventions:Monitor labs (WBC decrease, liver and kidney)Client educationMost commonly used: Spirolactone (aldactone)S/E: gynecomastia, testicular atrophy, hirsutism

  • Beta-adrenergic blockers

    Angiotensin converting enzyme (ACE) inhibitors

    Calcium channel blockers

  • Action/use:Inhibit cardiac response to sympathetic nerve stimulation (block the beta receptors)Decreases BP by decreasing cardiac output and heart rateDrugs of choice for Stage 1 & 2 hypertensionClinical advantages: Minimal postural or exercise hypotensionNo effect on sexual functionMinimal slowing of CNSPropranolol (Inderol)

  • S/E/contraindications:Bradycardia, peripheral vascular resistance, bronchospasm, wheezing, heart failure, hypoglycemia Dose relatedAvoid use in clients w asthma, type 1 diabetes, heart failure, peripheral vascular resistance diseaseNursing implications:Give lowest dose giving desired effectNeeds days-weeks to get optimal effectDo not d/c suddenly

  • Action/usePrevent angiotensin I converting to angiotensin II =no vasoconstriction, no aldosterone secretion, no sodium retentionPreserve cardiac output, increase renal blood flow; use with diureticDoes not aggrevate asthma, COPD, dia