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Pharmacology of Antiarrhythmics and Pharmacology of
Antiarrhythmics and Vasoactive SubstancesVasoactive Substances
Phillip L. Coule, M.D.Phillip L. Coule, M.D.Medical College of
Medical College of
GeorgiaGeorgiaDepartment of Department of
Emergency MedicineEmergency Medicine
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Please give proper credit to the Please give proper credit to
the author of this work:author of this work:
Phillip L. Coule, M.D.Phillip L. Coule, M.D.and the EMS Resource
Center at and the EMS Resource Center at the Medical College of
Georgiathe Medical College of
Georgiahttp://www.mcg.http://www.mcg.eduedu//somsom//emergemerg
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ObjectivesObjectives
■■ Overview of Antiarrhythmic and Vasoactive Overview of
Antiarrhythmic and Vasoactive MedicationsMedications••
actionsactions•• pharmacokineticspharmacokinetics••
indicationsindications•• dosing and Administrationdosing and
Administration•• adverse effectsadverse effects
■■ Classification of AntiarrhythmicsClassification of
Antiarrhythmics■■ Cardiac Arrest MedicationsCardiac Arrest
Medications
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Antiarrhythmic ClassificationAntiarrhythmic Classification
■■ Class I Class I -- Fast Channel BlockersFast Channel
Blockers•• Ia Ia -- Quinidine, Disopyramide, Quinidine,
Disopyramide,
ProcainamideProcainamide•• Ib Ib -- Lidocaine, Phenytoin,
Mexilitine, Lidocaine, Phenytoin, Mexilitine,
TocainindeTocaininde•• Ic Ic -- Ecainide, Flecainide,
Propafenone, Ecainide, Flecainide, Propafenone,
Indecainide, MoricizineIndecainide, Moricizine
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Antiarrhythmic Classification Antiarrhythmic Classification
■■ Class II Class II -- Beta BlockersBeta Blockers•• Propanolol,
Acebutolol, Atenolol, Betaxolol, Propanolol, Acebutolol, Atenolol,
Betaxolol,
Bisoprolol, Esmolol, Labetalol, Metoprolol, Bisoprolol, Esmolol,
Labetalol, Metoprolol, Nadolol, Oxprenolol, Penbutolol, Pindolol,
Nadolol, Oxprenolol, Penbutolol, Pindolol, Sotalol, TimololSotalol,
Timolol
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Antiarrhythmic ClassificationAntiarrhythmic Classification
■■ Class IIIClass III•• Bretylium, Amiodarone, SotalolBretylium,
Amiodarone, Sotalol
■■ Class IV Class IV -- Calcium Channel BlockersCalcium Channel
Blockers•• Verapamil, DiltiazemVerapamil, Diltiazem
■■ Unclassified Unclassified -- Digoxin, Adenosine, MgDigoxin,
Adenosine, Mg
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Procainamide Procainamide -- ActionsActions
■■ Suppresses automaticity Suppresses automaticity •• decreasing
the rate and amplitude of decreasing the rate and amplitude of
phase 4 diastolic depolarizationphase 4 diastolic
depolarization•• prolongs action potential durationprolongs action
potential duration•• reduces the speed of impulse conductionreduces
the speed of impulse conduction•• suppresses fibrillatory activity
in the atria suppresses fibrillatory activity in the atria
and ventriclesand ventricles■■ Dose dependant anticholinergic
activityDose dependant anticholinergic activity
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Procainamide Procainamide -- ActionsActions
■■ Negative InotropeNegative Inotrope•• more pronounced in
ischemic myocardiummore pronounced in ischemic myocardium
■■ Hypotension in high dosesHypotension in high doses••
vasodilatation of peripheral vasculaturevasodilatation of
peripheral vasculature
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ProcainamideProcainamide-- PharmacokineticsPharmacokinetics
■■ OnsetOnset•• 5 5 -- 10 minutes IV10 minutes IV•• 15 15 -- 60
minutes IM60 minutes IM
■■ Half LifeHalf Life•• 2.5 to 4.7 hrs in normal renal
function2.5 to 4.7 hrs in normal renal function•• increased in CHF,
Renal Failureincreased in CHF, Renal Failure
■■ Metabolized to NMetabolized to N--acetyl Procainamideacetyl
Procainamide•• NAPANAPA
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Procainamide Procainamide -- IndicationsIndications
■■ Ventricular arrhythmiasVentricular arrhythmias•• Stable
Ventricular TachycardiaStable Ventricular Tachycardia•• Premature
Ventricular ContractionsPremature Ventricular Contractions••
Ventricular Fibrillation / Pulseless VTVentricular Fibrillation /
Pulseless VT
■■ Supraventricular tachyarrhythmiasSupraventricular
tachyarrhythmias•• PSVT, PAT, paroxysmal AV junctionalPSVT, PAT,
paroxysmal AV junctional•• Atrial flutter and fibrillationAtrial
flutter and fibrillation
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ProcainamideProcainamide--
ContraindicationsContraindications
■■ AV block AV block •• Second or third degreeSecond or third
degree
■■ Long QT intervalLong QT interval■■ Torsade de pointesTorsade
de pointes■■ Caution Caution
•• SLE, CHF, hepatic or renal diseaseSLE, CHF, hepatic or renal
disease
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Procainamide Procainamide -- AdministrationAdministration
■■ Continuous infusion safer than bolusContinuous infusion safer
than bolus■■ Infusion of 20 Infusion of 20 -- 30 mg/min until30
mg/min until
•• control of arrhythmiacontrol of arrhythmia••
hypotensionhypotension•• QRS widens by > 50%QRS widens by >
50%•• QT interval prolongationQT interval prolongation•• Total of
17 mg/kg has been administeredTotal of 17 mg/kg has been
administered
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Procainamide Procainamide -- AdministrationAdministration
■■ Once ectopy is suppressedOnce ectopy is suppressed••
maintenance drip of 1 to 4 mg/minmaintenance drip of 1 to 4
mg/min
■■ Lower doses for CHF and renal failureLower doses for CHF and
renal failure
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Procainamide Procainamide -- Adverse EffectsAdverse Effects
■■ Myocardial DepressionMyocardial Depression•• prolonged QRS,
QT, AV conduction, VF prolonged QRS, QT, AV conduction, VF
and Torsade de pointesand Torsade de pointes■■
HypotensionHypotension
•• High doses or rapidly administeredHigh doses or rapidly
administered■■ HypersensitivityHypersensitivity
•• angioedema, bronchoconstriction, vascular angioedema,
bronchoconstriction, vascular collapse, febrile episodes,
respiratory collapse, febrile episodes, respiratory
arrestarrest
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Lidocaine Lidocaine -- ActionsActions
■■ Class IB antiarrhythmicClass IB antiarrhythmic•• blocks fast
sodium channelsblocks fast sodium channels•• decreases slope of
phase 4decreases slope of phase 4•• decreased automaticity in the
Hisdecreased automaticity in the His--purkinje purkinje
systemsystem•• action potential duration and effective action
potential duration and effective
refractory period of Hisrefractory period of His--purkinje
increasedpurkinje increased•• Acts preferentially on ischemic
tissueActs preferentially on ischemic tissue
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Lidocaine Lidocaine -- ActionsActions
■■ ContinuedContinued•• Causes little or no effect on AV
conductionCauses little or no effect on AV conduction•• Elevates
vElevates v--fib thresholdfib threshold•• Supresses ventricular
ectopySupresses ventricular ectopy•• negligible effect negligible
effect
–– autonomic nervous system autonomic nervous system ––
myocardial contractility myocardial contractility –– peripheral
vascular toneperipheral vascular tone
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Lidocaine Lidocaine --PharmacokineticsPharmacokinetics
■■ Onset of ActionOnset of Action•• 30 to 60 seconds IV30 to 60
seconds IV•• 10 minutes IM10 minutes IM
■■ Bolus administration necessaryBolus administration
necessary•• infusion alone will not reach therapeutic infusion
alone will not reach therapeutic
levels for 30 min to several hrs.levels for 30 min to several
hrs.■■ First pass metabolismFirst pass metabolism
•• No PO formNo PO form
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Lidocaine Lidocaine -- PharmacokineticsPharmacokinetics
■■ HalfHalf--Life (elimination)Life (elimination)•• 80 to 108
minutes 80 to 108 minutes
–– healthy patientshealthy patients•• 7 hrs 7 hrs
–– in patients with CHF, liver diseasein patients with CHF,
liver disease
■■ Therapeutic LevelsTherapeutic Levels•• 1.5 to 6 ug/ml1.5 to 6
ug/ml•• >5 ug/ml may cause CNS toxicity>5 ug/ml may cause CNS
toxicity
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Lidocaine Lidocaine -- IndicationsIndications
■■ Drug of Choice Drug of Choice •• ventricular
arrhythmiasventricular arrhythmias•• ventricular ectopyventricular
ectopy
–– frequent multifocal PVC’s (>6/min)frequent multifocal
PVC’s (>6/min)–– PVC couplets, salvosPVC couplets, salvos–– long
runs of VTlong runs of VT–– Not used for chronic PVC’s when
asymptomaticNot used for chronic PVC’s when asymptomatic
■■ Prophylactic use Prophylactic use •• No longer recommendedNo
longer recommended
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Lidocaine Lidocaine -- AdministrationAdministration
■■ Initial Dose IVInitial Dose IV•• Ventricular
EctopyVentricular Ectopy
–– 1 mg/kg bolus1 mg/kg bolus–– additional doses of 0.5 mg/kg q
5additional doses of 0.5 mg/kg q 5--10 min10 min
•• Ventricular FibrillationVentricular Fibrillation–– 1.5
mg/kg1.5 mg/kg
■■ Total Dose IVTotal Dose IV•• 3 mg/kg3 mg/kg
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Lidocaine Lidocaine -- AdministrationAdministration
■■ EndotrachealEndotracheal•• If IV not availableIf IV not
available•• 2 to 2 2 to 2 1/21/2 times the dose diluted to total
times the dose diluted to total
volume of 10 cc’svolume of 10 cc’s■■ IMIM
•• 300 mg of 10% solution, deltoid vastus 300 mg of 10%
solution, deltoid vastus lateralis lateralis
•• AutoAuto-- injectors availableinjectors available
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Lidocaine Lidocaine -- Adverse EffectsAdverse Effects
■■ CNS side effectsCNS side effects■■ Abrupt change in mental
statusAbrupt change in mental status■■ Plasma levels greater than 9
ug/mlPlasma levels greater than 9 ug/ml
•• psychosis, seizures, respiratory depressionpsychosis,
seizures, respiratory depression■■
ContraindicatedContraindicated
•• SA or AV blocksSA or AV blocks•• Known hypersensitivityKnown
hypersensitivity
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Beta Blockers Beta Blockers -- ActionsActions
■■ Block effects of catacholamines on Beta Block effects of
catacholamines on Beta receptorsreceptors
■■ Selective Beta blockersSelective Beta blockers•• metoprolol
metoprolol •• acebutololacebutolol•• atenololatenolol••
esmololesmolol•• metoprololmetoprolol
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Beta Blockers Beta Blockers -- ActionsActions
■■ NegativeNegative•• ChronotropicChronotropic
–– slows sinus rateslows sinus rate–– depresses AV
conductiondepresses AV conduction–– Decreases cardiac
outputDecreases cardiac output
•• InotropicInotropic■■ VasodilatationVasodilatation
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Beta BlockersBeta Blockers--
PharmacokineticsPharmacokinetics
■■ OnsetOnset•• rapid rapid -- within 1 minute IVwithin 1 minute
IV
■■ Half Life Half Life •• 1 to 26 hours1 to 26 hours•• Excretion
is renal and GIExcretion is renal and GI
■■ Dose adjustment necessary for renal Dose adjustment necessary
for renal failure for some beta blockers failure for some beta
blockers
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Beta Blockers Beta Blockers -- AdministrationAdministration
■■ MetoprololMetoprolol•• 5 mg IV push5 mg IV push•• selective
B1selective B1•• Half life of 3Half life of 3--7 hrs7 hrs
■■ EsmololEsmolol•• ultraultra--short half life of 9
minutesshort half life of 9 minutes•• 2525--50 ug/kg/min50
ug/kg/min•• load of 500 ug/kg not necessaryload of 500 ug/kg not
necessary
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Beta Blockers Beta Blockers -- Adverse EffectsAdverse
Effects
■■ Similar for most Beta blockersSimilar for most Beta
blockers•• nausea, vomiting, light headedness, nausea, vomiting,
light headedness,
mental depression, bradycardia, mental depression, bradycardia,
hypotension, bronchospasmhypotension, bronchospasm
■■ ContraindicatedContraindicated•• > first degree heart
block> first degree heart block•• CHF or cardiogenic shockCHF or
cardiogenic shock•• Caution with calcium channel blockersCaution
with calcium channel blockers
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Bretylium Bretylium -- ActionsActions
■■ Class IIIClass III■■ Biphasic EffectsBiphasic Effects
•• Norepinephrine releaseNorepinephrine release–– effects last
20 minuteseffects last 20 minutes
•• Blocks release of norepinephrineBlocks release of
norepinephrine–– 45 to 60 minutes after administration45 to 60
minutes after administration
•• Affects phase 3 (repolarization) prolongs Affects phase 3
(repolarization) prolongs refractoriness refractoriness --
antifibrillatoryantifibrillatory
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Bretylium Bretylium -- IndicationsIndications
■■ VFVF•• refractory VF, after epinephrine, lidocainerefractory
VF, after epinephrine, lidocaine
■■ VTVT•• refractory VT with a pulse, after lidocaine refractory
VT with a pulse, after lidocaine
and procainamideand procainamide■■ Wide Complex Tachycardia
UnknownWide Complex Tachycardia Unknown
•• after lidocaine and adenosineafter lidocaine and
adenosine
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Bretylium Bretylium -- AdministrationAdministration
■■ VF or Pulseless VTVF or Pulseless VT•• 5 mg/kg rapid IV push5
mg/kg rapid IV push•• repeat at 10 mg/kg in 15 to 30 minutesrepeat
at 10 mg/kg in 15 to 30 minutes•• maximum is 35 mg/kgmaximum is 35
mg/kg
■■ VT / ventricular arrhythmiasVT / ventricular arrhythmias•• 5
5 -- 10 mg.kg over 8 to 10 minutes10 mg.kg over 8 to 10 minutes
■■ Maintenance of 1Maintenance of 1--2 mg/min2 mg/min
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Diltiazem Diltiazem -- ActionsActions
■■ Class IV Class IV -- Calcium Channel BlockerCalcium Channel
Blocker•• decreases conduction velocity in diseased decreases
conduction velocity in diseased
tissuetissue•• prolongs refractory period in AV nodeprolongs
refractory period in AV node•• slows discharge from SA nodeslows
discharge from SA node•• minimal effect on normal tissue minimal
effect on normal tissue •• Interrupts reentrant pathway in
PSVTInterrupts reentrant pathway in PSVT
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Diltiazem Diltiazem -- IndicationsIndications
■■ Rapid Conversion of PSVTRapid Conversion of PSVT•• as
effective as adenosine and verapamilas effective as adenosine and
verapamil
■■ Slowing of rate in ASlowing of rate in A--Fib or AFib or
A--flutterflutter■■ HypertensionHypertension
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Diltiazem Diltiazem -- AdministrationAdministration
■■ PSVT, APSVT, A--fib, Afib, A--flutterflutter•• .25 mg/kg
(average 20 mg) over 2 minutes.25 mg/kg (average 20 mg) over 2
minutes•• Second bolus of .35 mg/kgSecond bolus of .35 mg/kg
■■ Maintenance InfusionMaintenance Infusion•• 55--15 mg/hr15
mg/hr
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Diltiazem Diltiazem -- Adverse EffectsAdverse Effects
■■ CardiovascularCardiovascular•• angina, bradycardia, asystole,
CHF, AV angina, bradycardia, asystole, CHF, AV
block, BBB, flushing, hypotensionblock, BBB, flushing,
hypotension■■ NonNon--cardiovascularcardiovascular
•• headache, dizziness, constipation, rashheadache, dizziness,
constipation, rash
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Adenosine Adenosine -- ActionsActions
■■ Endogenous NucleosideEndogenous Nucleoside•• produced by
dephosphorylation of ATPproduced by dephosphorylation of ATP
■■ Negative Chronotropic effects on SA Negative Chronotropic
effects on SA and AV nodeand AV node•• Does not alter accessory
pathwaysDoes not alter accessory pathways•• blockade of the AV
nodeblockade of the AV node•• potent vasodilator potent vasodilator
-- no effects due to no effects due to
metabolismmetabolism
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Adenosine Adenosine -- PharmacokineticsPharmacokinetics
■■ OnsetOnset•• 30 seconds30 seconds
■■ Duration Duration •• 60 to 90 seconds60 to 90 seconds
■■ HalfHalf--life life •• less than 7 secondsless than 7
seconds
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Adenosine Adenosine -- IndicationsIndications
■■ Emergency management of PSVTEmergency management of PSVT••
involving the AV nodeinvolving the AV node
■■ DiagnosticDiagnostic•• Wide complex tachycardia of uncertain
Wide complex tachycardia of uncertain
originorigin•• detection of accessory pathwaysdetection of
accessory pathways
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Adenosine Adenosine -- AdministrationAdministration
■■ 6 mg Rapid IV push (over 16 mg Rapid IV push (over 1--2
seconds)2 seconds)•• most proximal portmost proximal port••
followed by 20 ml saline flushfollowed by 20 ml saline flush••
elevate the extremity after boluselevate the extremity after
bolus
■■ Repeat DosingRepeat Dosing•• 12 mg rapid IV push if heart
rate not 12 mg rapid IV push if heart rate not
decreased in 2 minutesdecreased in 2 minutes
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Adenosine Adenosine -- Adverse EffectsAdverse Effects
■■ Minor and well toleratedMinor and well tolerated•• less than
1 minuteless than 1 minute•• dyspnea, cough, syncope, vertigo,
dyspnea, cough, syncope, vertigo,
parasthesiasparasthesias■■ Higher dosesHigher doses
•• DipyramidoleDipyramidole•• CarbamazepineCarbamazepine••
Asthmatics, excessive coffee drinkersAsthmatics, excessive coffee
drinkers
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Magnesium Magnesium -- ActionsActions
■■ DirectlyDirectly•• Na, K+, ATPase pumpNa, K+, ATPase pump
■■ IndirectlyIndirectly•• calcium channel blocking
activitycalcium channel blocking activity
■■ EffectsEffects•• Increases membrane potentialIncreases
membrane potential•• prolongs AV conductionprolongs AV conduction••
Corrects hypomagnesemia/hypokalemiaCorrects
hypomagnesemia/hypokalemia
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Magnesium Magnesium -- IndicationsIndications
■■ Intractable VF/VTIntractable VF/VT■■ Torsade de
pointesTorsade de pointes■■ May be usefulMay be useful
•• PVC’s, MAT, PSVT, digoxin toxicityPVC’s, MAT, PSVT, digoxin
toxicity
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Magnesium Magnesium -- AdministrationAdministration
■■ IV Loading doseIV Loading dose•• 1 to 2 grams in 501 to 2
grams in 50--100 cc of D5W over 1 to 100 cc of D5W over 1 to
2 minutes2 minutes■■ Acute MIAcute MI
•• 8 to 12 grams per day in acute MI8 to 12 grams per day in
acute MI
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Vasoactive MedicationsVasoactive Medications
■■ EpinephrineEpinephrine■■ DopamineDopamine■■
NorepinephrineNorepinephrine■■ AtropineAtropine■■
NitroglycerinNitroglycerin
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Epinephrine Epinephrine -- OverviewOverview
■■ Nonselective alpha and beta agonistNonselective alpha and
beta agonist•• increased heart rate, SVR, ventricular increased
heart rate, SVR, ventricular
contractilitycontractility■■ Onset Onset
•• 1 to 2 minutes1 to 2 minutes■■ Duration of action Duration of
action
•• 2 to 10 minutes2 to 10 minutes
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Epinephrine Epinephrine -- ContinuedContinued
■■ IndicationsIndications•• Cardiac ArrestCardiac Arrest••
Bronchospasm Bronchospasm •• Anaphylaxis / hypersensitivity
reactionsAnaphylaxis / hypersensitivity reactions
■■ AdministrationAdministration•• Cardiac ArrestCardiac
Arrest
–– 1 mg IV push every 3 1 mg IV push every 3 -- 5 minutes5
minutes–– escalating and high dose optionsescalating and high dose
options
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Epinephrine Epinephrine -- ContinuedContinued
•• EndotrachealEndotracheal–– 2 to 2.5 the IV dose diluted to 10
cc2 to 2.5 the IV dose diluted to 10 cc
■■ Adverse EffectsAdverse Effects•• may increase myocardial
oxygen may increase myocardial oxygen
consumptionconsumption
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Dopamine Dopamine -- OverviewOverview
■■ ActionsActions•• acts on dopaminergic, alpha and beta acts on
dopaminergic, alpha and beta
receptorsreceptors■■ Low DoseLow Dose
•• dilatation of renal, mesenteric, coronary, dilatation of
renal, mesenteric, coronary, and intracerebral vascular bedsand
intracerebral vascular beds
•• improves organ perfusion and increases improves organ
perfusion and increases urine outputurine output
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Dopamine Dopamine -- ContinuedContinued
■■ Moderate Dose 2 Moderate Dose 2 -- 10 ug/kg/min10 ug/kg/min••
mostly beta effects mostly beta effects
–– inotropic, chronotropic on heartinotropic, chronotropic on
heart–– increased cardiac outputincreased cardiac output
■■ High Dose >10 ug/kg/minHigh Dose >10 ug/kg/min•• Alpha
effects predominateAlpha effects predominate
–– increased peripheral resistanceincreased peripheral
resistance–– decreased blood flow to kidneydecreased blood flow to
kidney
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Norepinephrine Norepinephrine -- OverviewOverview
■■ Endogenous CatacholamineEndogenous Catacholamine•• powerful
alpha agonistpowerful alpha agonist•• potent vasoconstrictorpotent
vasoconstrictor
■■ Onset Onset •• 1 to 3 minutes1 to 3 minutes
■■ IndicationsIndications•• severe hypotension refractory to
fluids and severe hypotension refractory to fluids and
other pressor agentsother pressor agents
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Norepinephrine Norepinephrine -- ContinuedContinued
■■ Specific UsesSpecific Uses•• Septic ShockSeptic Shock••
refractory hypotension due to AMIrefractory hypotension due to
AMI
■■ DosingDosing•• 0.5 to 1 ug/kg/min0.5 to 1 ug/kg/min
–– increase by 1 to 2 ug/kg/min every 3increase by 1 to 2
ug/kg/min every 3--5 min 5 min –– goal is systolic BP of 80 to 100
goal is systolic BP of 80 to 100
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Phillip L. Coule, M.D. Medical College of Georgia Emergency
MediPhillip L. Coule, M.D. Medical College of Georgia Emergency
Medicinecine
Norepinephrine Norepinephrine -- ContinuedContinued
■■ Adverse EffectsAdverse Effects•• ventricular
irritabilityventricular irritability•• cardiac depressioncardiac
depression•• decreased renal blood flowdecreased renal blood flow••
reflex bradycardiareflex bradycardia•• acute hypertensionacute
hypertension
–– MAOI, TCA’sMAOI, TCA’s•• Extravasation necrosisExtravasation
necrosis
–– pentolamine 5pentolamine 5--10 mg/10 cc subcutaneous10 mg/10
cc subcutaneous
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Phillip L. Coule, M.D. Medical College of Georgia Emergency
MediPhillip L. Coule, M.D. Medical College of Georgia Emergency
Medicinecine
Atropine OverviewAtropine Overview
■■ Antimuscarinic AgentAntimuscarinic Agent•• parasympatholytic
/ vagolyticparasympatholytic / vagolytic
–– increases SA node automaticity by blocking increases SA node
automaticity by blocking vagus nervevagus nerve
■■ IndicationsIndications•• hemodynamically unstable
bradycardiashemodynamically unstable bradycardias•• PEA, Asystole,
bradyasystolic rhythmsPEA, Asystole, bradyasystolic rhythms••
anticholinergic propertiesanticholinergic properties
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Phillip L. Coule, M.D. Medical College of Georgia Emergency
MediPhillip L. Coule, M.D. Medical College of Georgia Emergency
Medicinecine
Atropine ContinuedAtropine Continued
■■ DoseDose•• 0.5 to 1 mg IV0.5 to 1 mg IV
■■ EndotrachealEndotracheal•• 1 to 2 mg IV (10 cc volume)1 to 2
mg IV (10 cc volume)
■■ Adverse effectsAdverse effects•• increased MVO2increased
MVO2•• undesirable tachycardiaundesirable tachycardia•• precipitate
ventricular arrhythmiasprecipitate ventricular arrhythmias
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Phillip L. Coule, M.D. Medical College of Georgia Emergency
MediPhillip L. Coule, M.D. Medical College of Georgia Emergency
Medicinecine
SummarySummary
■■ Pharmacology of antiarrhythmic and Pharmacology of
antiarrhythmic and vasoactive medicationsvasoactive medications••
ActionsActions•• PharmacokineticsPharmacokinetics••
IndicationsIndications•• AdministrationAdministration•• Adverse
EffectsAdverse Effects