Cardiac/Vascular CirculationCardiac/Vascular Circulation

Brenda Rowe, RN, MN, JDBrenda Rowe, RN, MN, JD

Georgia Baptist College of Nursing Georgia Baptist College of Nursing

of Mercer Universityof Mercer University

C.O. = Stroke Vol. X Heart C.O. = Stroke Vol. X Heart RateRate

Preload - passive stretching force Preload - passive stretching force exerted on ventricle muscleexerted on ventricle muscle

Contractility - force of the squeezing Contractility - force of the squeezing that the ventricle is able to achievethat the ventricle is able to achieve

Afterload - amount of pressure the Afterload - amount of pressure the ventricle muscle must overcome to ejectventricle muscle must overcome to eject

Contraction - dependent upon Contraction - dependent upon conduction systemconduction system

Cardiac Effects of DigoxinCardiac Effects of Digoxin

Positive inotropin effect: strengthens Positive inotropin effect: strengthens the force of contractionthe force of contraction

Negative dromotropin effect: Negative dromotropin effect: decreases conductiondecreases conduction

Negative chronotropin effect: Negative chronotropin effect: decreases heart ratedecreases heart rate

Improve renal perfusionImprove renal perfusion

DigoxinDigoxin* CHF, atrial fib* CHF, atrial fib

* digitalization* digitalization

* toxic effects - N&V, diarrhea, * toxic effects - N&V, diarrhea, green/yellow vision, double green/yellow vision, double vision, headache, dizziness, vision, headache, dizziness, fatigue, weaknessfatigue, weakness

* monitor effectiveness* monitor effectiveness

* watch for hypokalemia* watch for hypokalemia

* education* education

* antidote - digoxin immune * antidote - digoxin immune FABFAB

Nursing InterventionsNursing Interventions

Monitor HR - apical for 1 minuteMonitor HR - apical for 1 minute Monitor Dig level - 0.5-2.0 ng/mlMonitor Dig level - 0.5-2.0 ng/ml Monitor K, Calcium, Mag - increase in Monitor K, Calcium, Mag - increase in

calcium or decrease in K or Mag will calcium or decrease in K or Mag will potentiate the effect of Digoxinpotentiate the effect of Digoxin

Other Cardiac GlycosidesOther Cardiac Glycosides

inamrinone (Inocor) & milrinone inamrinone (Inocor) & milrinone (Primacor): increase force of (Primacor): increase force of contraction and produce a contraction and produce a vasodilatory effect which increases vasodilatory effect which increases cardiac outputcardiac output

Used for short term management of Used for short term management of CHFCHF

Critical Thinking ExerciseCritical Thinking Exercise

A patient with CHFA patient with CHF Is on Digoxin, Lasix, and potassium Is on Digoxin, Lasix, and potassium

supplementsupplement What is the desired therapeutic effect?What is the desired therapeutic effect? Why should hypokalemia be prevented?Why should hypokalemia be prevented? What blood work should be monitored?What blood work should be monitored?

NitroglycerinNitroglycerin

Relaxes vascular smooth muscles & Relaxes vascular smooth muscles & dilates arterial & venous vessels thus dilates arterial & venous vessels thus reducing afterload & myocardial reducing afterload & myocardial consumptionconsumption

Acute angina: sublingual, transmucosal, Acute angina: sublingual, transmucosal, or translingual sprayor translingual spray

Prophylactic for angina: above & topical Prophylactic for angina: above & topical & oral SR& oral SR

IV: used to treat primarily hypertensionIV: used to treat primarily hypertension

Tolerance & Adverse EffectsTolerance & Adverse Effects

Tolerance may developTolerance may develop Less likely in sublingual & Less likely in sublingual &

translingual spraytranslingual spray Most common adverse effects: Most common adverse effects:

headache, can have hypotension, headache, can have hypotension, tachycardia, syncopetachycardia, syncope

Anginal EpisodeAnginal Episode

Have a person lie downHave a person lie down Give nitroglycerin tabs x 3, if needed, Give nitroglycerin tabs x 3, if needed,

5 minutes apart5 minutes apart If no relief – call 911If no relief – call 911

EducationEducation

Smoking causes vasoconstriction Smoking causes vasoconstriction which may cause anginawhich may cause angina

Sublingual: keep in original bottle Sublingual: keep in original bottle with tight capwith tight cap

Transdermal: nonhairy area but Transdermal: nonhairy area but avoid distal parts of extremities, avoid distal parts of extremities, remove patch for 10-12 hoursremove patch for 10-12 hours

Education (cont.)Education (cont.)

Increase absorption with broken skin, Increase absorption with broken skin, increase with exercise, increase increase with exercise, increase temperature (avoid sauna)temperature (avoid sauna)

Ointment: choose a different Ointment: choose a different application site, use tissue to remove application site, use tissue to remove any old ointment, do not massage or any old ointment, do not massage or rub in ointmentrub in ointment

AntiarrhythmicsAntiarrhythmics

* see after MI, cardiac * see after MI, cardiac surgery, CAD, electrolyte surgery, CAD, electrolyte imbalance, thyroid diseaseimbalance, thyroid disease

* abnormality with initiation * abnormality with initiation of impulse or in impulse of impulse or in impulse conduction or bothconduction or both

* should be monitored, most * should be monitored, most meds given IV, monitor AP meds given IV, monitor AP (rate & rhythm)(rate & rhythm)

Antiarrhythmic AgentsAntiarrhythmic AgentsQuinidine (Cardioquin)Quinidine (Cardioquin) – class – class 1A depresses Phase 0 in 1A depresses Phase 0 in depolarizationdepolarization

* depresses cardiac function, * depresses cardiac function, however inhibits vagal action however inhibits vagal action so may have sinus so may have sinus tachycardiatachycardia

* has high incidence of * has high incidence of adverse effects with most adverse effects with most common being GIcommon being GI

* monitor renal & liver * monitor renal & liver functionfunction

LidocaineLidocaine

Lidocaine (Xylocaine)Lidocaine (Xylocaine) - Class 1B - Class 1B depresses phase 0 but not as much depresses phase 0 but not as much as Quinidineas Quinidine

brief action so less chance of brief action so less chance of cumulative drug toxicity, make sure cumulative drug toxicity, make sure you have correct type of Lidocaine, you have correct type of Lidocaine, tx ventricular arrhythmiastx ventricular arrhythmias

give IVgive IV

Antiarrhythmic Agents Antiarrhythmic Agents (cont.)(cont.)

Flecainide (Tambocor)Flecainide (Tambocor) - Class - Class 1C markedly depresses phase 1C markedly depresses phase 0, tx PAF or flutter & 0, tx PAF or flutter & ventricular arrhymias, ventricular arrhymias, suppress conduction, many suppress conduction, many adverse effectsadverse effects

Propranolol (Inderal)Propranolol (Inderal) - Class II - Class II depresses phase 4 depresses phase 4 depolarization, beta depolarization, beta adrenergic blocking agent, tx adrenergic blocking agent, tx arrhythmias secondary to dig arrhythmias secondary to dig toxicity, also used to tx toxicity, also used to tx hypertension, angina & MIhypertension, angina & MI

amiodarone (Cordarone)amiodarone (Cordarone)

Amiodarone (Cordarone)Amiodarone (Cordarone) - Class III - Class III prolongs phase III repolarizationprolongs phase III repolarization

increases refractory period, increases increases refractory period, increases myocardial contractility, vasodilatory myocardial contractility, vasodilatory actionaction

used to prophylaxis and therapy of vent used to prophylaxis and therapy of vent fibfib

keep pt supine - most common AE is keep pt supine - most common AE is orthostatic hypotensionorthostatic hypotension

Verapamil HCL (Calan)Verapamil HCL (Calan) Class IV depresses phase 4 depolarization Class IV depresses phase 4 depolarization

& lengthens phase 1 & 2 of repolarization& lengthens phase 1 & 2 of repolarization calcium channel blocker, decrease calcium channel blocker, decrease

myocardial contraction, decrease SA node myocardial contraction, decrease SA node impulse, decrease conduction, also causes impulse, decrease conduction, also causes CA dilatation & peripheral vasodilatationCA dilatation & peripheral vasodilatation

also used to tx anginaalso used to tx angina watch for bradycardia & hypotensionwatch for bradycardia & hypotension AE - most common is constipationAE - most common is constipation IV solution must be protected from lightIV solution must be protected from light Administer slowly – greater than 2 minutesAdminister slowly – greater than 2 minutes

Potassium-Removing ResinsPotassium-Removing Resins

Sodium polystyrene sulfonate Sodium polystyrene sulfonate (Kayexalate)(Kayexalate)

oral or enemaoral or enema AE - hypokalemiaAE - hypokalemia

AntihyperlipidemicsAntihyperlipidemics

DefinitionDefinition HDL/LDLHDL/LDL

StatinsStatins

lovastatin (Mevacor)lovastatin (Mevacor) Blocks synthesis of cholesterol in Blocks synthesis of cholesterol in

liverliver Decrease LDL, increase HDLDecrease LDL, increase HDL

Bile acid sequestrantsBile acid sequestrants

cholestyramine (Questran)cholestyramine (Questran) Lower LDL levelsLower LDL levels Binds bile acids in intestineBinds bile acids in intestine

New drugsNew drugs

How actions differHow actions differ