Transcript Pharmacology Review - Madison County Emergency Medical District

Cardiac Pharmacology Review
Matthew R. Paulus, RN, MS, EMT-P,
CNP, ANP-BC
Objectives
• To review and obtain a better
understanding of medications used in
ACLS
– Indications & Actions (When & Why?)
– Dosing (How?)
– Contraindications & Precautions (Watch Out!)
2
3
Drug Classifications
• Class I: Recommendations
– Excellent evidence provides support
– Proven in both efficacy and safety
• Class II: Recommendations
– Level I studies are absent, inconsistent
or lack power
– Available evidence is positive but may
lack efficacy
– No evidence of harm
4
Drug Classifications
• Class IIa Vs IIb
– Class IIa recommendations have
• Higher level of available evidence
• Better critical assessments
• More consistency in results
– Both are optional and acceptable,
– IIa recommendations are probably useful
– IIb recommendations are possibly helpful
• Less compelling evidence for efficacy
5
Drug Classifications
• Class III: Not recommended
– Not acceptable or useful and may be harmful
– Evidence is absent or unsatisfactory, or based
on poor studies
• Indeterminate
– Continuing area of research; no
recommendation until further data is available
6
Drug used in Resuscitation
Oxygen
• Indications (When & Why?)
–
–
–
–
Any suspected cardiopulmonary emergency
Saturate hemoglobin with oxygen
Reduce anxiety & further damage
Note: Pulse oximetry should be monitored
Universal8Algorithm
Oxygen
• Precautions (Watch Out!)
– Pulse oximetry inaccurate in:
• Low cardiac output
• Vasoconstriction
• Hypothermia
Universal9Algorithm
Epinephrine
• Indications
– VF/Pulseless VT, Anaphylaxis
– Increases:
• Heart rate
• Force of contraction
• Conduction velocity
– Peripheral vasoconstriction
– Bronchial dilation
10
Epinephrine
• Dosing (How?)
– 1 mg IV push; may repeat every 3 to 5 minutes
– 0.3mg of 1:1,000 SQ for Anaphylaxis
– 0.1mg to 0.3mg IV for severe 1:10,000 SIVP
11
Epinephrine
• Precautions (Watch Out!)
– Raising blood pressure and increasing heart
rate may cause myocardial ischemia, angina,
and increased myocardial oxygen demand
– Higher doses have not improved outcome &
may cause myocardial dysfunction
12
Vasopressin
• Indications
–
–
–
–
–
Alternative to EPI in VF/Pulseless VT
Potent peripheral vascular agent
Used to “clamp” down on vessels
Improves perfusion of heart, lungs, and brain
No direct effects on heart
13
Vasopressin
• Dosing (How?)
– One time dose of 40 units only
– May be initially substituted for epinephrine
14
Vasopressin
• Precautions (Watch Out!)
– May result in an initial increase in blood
pressure immediately following return of pulse,
which is not necessarily a bad thing.
– May provoke cardiac ischemia
15
Amiodarone
• Indications (When & Why?)
– Powerful antiarrhythmic with substantial toxicity,
especially in the long term
– Intravenous and oral behavior are quite
different
– Has effects on sodium & potassium
VF / Pulseless
VT
16
Amiodarone
• Dosing (How?)
– Should be diluted
• 300 mg bolus after first Epinephrine dose
• Repeat doses at 150 mg
-150 mg given over ten minutes
VF / Pulseless
VT
17
Amiodarone
• Precautions (Watch Out!)
– May produce vasodilation & shock
– May have negative inotropic effects
– Terminal elimination
• Half-life lasts up to 40 days
VF / Pulseless
VT
18
Lidocaine
• Indications (When & Why?)
–
–
–
–
–
Ventricular Dysrhythmias
Depresses automaticity
Depresses excitability
Raises ventricular fibrillation threshold
Decreases ventricular irritability
VF / Pulseless
VT
19
Lidocaine
• Dosing (How?)
– Initial dose: 1.0 to 1.5 mg/kg IV
– For refractory VF may repeat 1.0 to 1.5 mg/kg
IV in 3 to 5 minutes; maximum total dose, 3
mg/kg
– A single dose of 1.5 mg/kg IV in cardiac arrest
is acceptable.
VF / Pulseless
VT
20
Lidocaine
• Dosing (How?)
– Maintenance Infusion
• 2 to 4 mg/min
• Lidocaine Clock
– 15 mL/hr = 1 mg/min
– 30 mL/hr = 2 mg/min
– 45 mL/hr = 3 mg/min
– 60 mL/hr = 4 mg/min
VF / Pulseless
VT
21
Lidocaine
• Precautions (Watch Out!)
– Reduce maintenance dose (not loading dose) in
presence of impaired liver function or left
ventricular dysfunction
22
Atropine Sulfate
• Indications (When & Why?)
– Used to increase heart rate
– Via decrease in parasympathetic inhibition of
SA node.
– In essence, encourages increase in P-wave
production.
– This is why it is NOT used in higher grade AVB
– Its utility in Asystole has been changed in
recent years.
23
Atropine Sulfate
• Dosing (How?)
– 1 mg IV push
– Repeat every 3 to 5 minutes
– Maximum Dose: 0.04 mg/kg
24
Atropine Sulfate
• Precautions (Watch Out!)
– Increases myocardial oxygen demand
25
Sodium Bicarbonate
• Indications (When & Why?)
– Class I if known preexisting
hyperkalemia
– Class IIa if known preexisting
bicarbonate-responsive acidosis
– Class IIb if prolonged resuscitation with
effective ventilation; upon return of
spontaneous circulation
– Class III (not useful or effective) in
hypoxic lactic acidosis or hypercarbic
acidosis (eg, cardiac arrest and CPR
without26intubation)
Sodium Bicarbonate
• Dosing (How?)
– 1 mEq/kg IV bolus
– Repeat half this dose every 10 minutes
thereafter
– If rapidly available, use arterial blood gas
analysis to guide bicarbonate therapy
(calculated base deficits or bicarbonate
concentration)
Other Cardiac
27 Arrest Drugs
Sodium Bicarbonate
• Precautions (Watch Out!)
– Adequate ventilation and CPR, not bicarbonate,
are the major "buffer agents" in cardiac arrest
– Not recommended for routine use in cardiac
arrest patients
Other Cardiac
28 Arrest Drugs
Acute Coronary
Syndromes/Dysrhythmia
• ST elevation or new or
presumably new LBBB:
strongly suspicious for
injury
• ST-elevation AMI
• ST depression or dynamic
T-wave inversion:
strongly suspicious
for ischemia
• High-risk unstable angina/
non–ST-elevation AMI
29
• Nondiagnostic ECG:
absence of changes
in ST segment or
T waves
• Intermediate/low-risk
unstable angina
ST Elevation
30
Recognition
of AMI
• Know what to look
for—
J point plus
0.04 second
– ST elevation >1 mm
– 3 contiguous leads
PR baseline
ST-segment deviation
= 4.5 mm
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ST Elevation
Baseline
Ischemia—tall or inverted T wave (infarct),
ST segment may be depressed (angina)
Injury—elevated ST segment, T wave may
invert
Infarction (Acute)—abnormal Q wave,
ST segment may be elevated and T wave
may be inverted
Infarction (Age Unknown)—abnormal Q wave,
ST segment and T wave returned to normal
32
Aspirin
• Indications (When & Why?)
– Administer to all patients with ACS, particularly
reperfusion candidates
• Give as soon as possible
– Blocks formation of thromboxane A2, which
causes platelets to aggregate
Acute Coronary
33 Syndromes
Aspirin
• Dosing (How?)
– 160 to 325 mg tablets
• Preferably chewed
• May use suppository
– Higher doses may be harmful
Acute Coronary
34 Syndromes
Aspirin
• Precautions (Watch Out!)
– Relatively contraindicated in patients with active
ulcer disease or asthma
Acute Coronary
35 Syndromes
Nitroglycerine
• Indications (When & Why?)
– Chest pain of suspected cardiac origin
– Unstable angina
– Complications of AMI, including congestive
heart failure, left ventricular failure
– Hypertensive crisis or urgency with chest pain
Acute Coronary
36 Syndromes
Nitroglycerin
•
Indications (When & Why?)
–
–
–
–
Decreases pain of ischemia
Increases venous dilation
Decreases venous blood return to heart
Decreases preload and cardiac
oxygen consumption
– Dilates coronary arteries
– Increases cardiac collateral flow
Acute Coronary
37 Syndromes
Nitroglycerine
• Dosing (How?)
– Sublingual Route
• 0.3 to 0.4 mg; repeat every 5 minutes
– Aerosol Spray
• Spray for 0.5 to 1.0 second at 5 minute
intervals
– IV Infusion
• Infuse at 10 to 20 µg/min
• Route of choice for emergencies
• Titrate to effect
Acute Coronary
38 Syndromes
Nitroglycerine
• Precautions (Watch Out!)
– Use extreme caution if systolic BP <90
mm Hg
– Use extreme caution in RV infarction
– Suspect RV infarction with inferior ST
changes
– Limit BP drop to 10% if patient is
normotensive
– Limit BP drop to 30% if patient is
hypertensive
– Watch for headache, drop in BP,
syncope,
tachycardia
Acute
Coronary
39 Syndromes
– Tell patient to sit or lie down during
Morphine Sulfate
• Indications (When & Why?)
– Chest pain and anxiety associated with AMI or
cardiac ischemia
– Acute cardiogenic pulmonary edema (if blood
pressure is adequate)
Acute Coronary
40 Syndromes
Morphine Sulfate
• Indications (When & Why?)
– To reduce pain of ischemia
– To reduce anxiety
– To reduce extension of ischemia by reducing
oxygen demands
Acute Coronary
41 Syndromes
Morphine Sulfate
• Dosing (How?)
– 1 to 3 mg IV (over 1 to 5 minutes) every 5 to 10
minutes as needed
Acute Coronary
42 Syndromes
Morphine Sulfate
• Precautions (Watch Out!)
– Administer slowly and titrate to effect
– May compromise respiration; therefore use with
caution in acute pulmonary edema
– Causes hypotension in volume-depleted
patients
Acute Coronary
43 Syndromes
Beta Blockers

Indications (When & Why?)
– To reduce myocardial ischemia and damage
in AMI patients with elevated heart rates,
blood pressure, or both
– Blocks catecholamines from binding to
ß-adrenergic receptors
– Reduces HR, BP, myocardial contractility
– Decreases AV nodal conduction
– Decreases incidence of primary VF
Acute Coronary Syndromes
44
Beta Blockers

Precautions (Watch Out!)
– Concurrent IV administration with IV calcium
channel blocking agents like verapamil or diltiazem
can cause severe hypotension
– Avoid in bronchospastic diseases, cardiac failure, or
severe abnormalities in cardiac conduction
– Monitor cardiac and pulmonary status during
administration
– May cause myocardial depression
Acute Coronary Syndromes
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PTCA
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ACE Inhibitors

Precautions (Watch Out!)
– Contraindicated in pregnancy
– Contraindicated in angioedema
– Reduce dose in renal failure
– Avoid hypotension, especially following initial
dose & in relative volume depletion
Acute Coronary Syndromes
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Furosemide

Indications (When & Why?)
– For adjuvant therapy of acute pulmonary
edema in patients with systolic blood
pressure >90 to 100 mm Hg (without S/S of
shock)
– Hypertensive emergencies
– CHF
– Increased intracranial pressure
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Furosemide

Dosing (How?)
– 20 to 40 mg slow IVP
– If patient is taking at home, double their daily
dose
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Furosemide

Precautions (Watch Out!)
– Dehydration, hypovolemia, hypotension,
hypokalemia, or other electrolyte imbalance
may occur
50
Antiarrhythmics

Vaughn Williams Classifications:
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Antiarrhythmics

The Cardiac Cycle
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Diltiazem

Indications (When & Why?)
– To control ventricular rate in atrial fibrillation
and atrial flutter
– Use after adenosine to treat refractory PSVT
in patients with narrow QRS complex and
adequate blood pressure
– Has replaced verapamil…much less side
effects.
53
Diltiazem

Dosing (How?)
– Acute Rate Control
 15
to 20 mg (0.25 mg/kg) IV over 2 minutes
 May repeat in 15 minutes at 20 to 25 mg (0.35
mg/kg) over 2 minutes
– Maintenance Infusion
5
to 15 mg/hour, titrated to heart rate
54
Diltiazem

Precautions (Watch Out!)
– Avoid calcium channel blockers in patients with
Wolff-Parkinson-White syndrome, in patients with
sick sinus syndrome, or in patients with AV block
without a pacemaker
– Expect blood pressure drop resulting from
peripheral vasodilation
– Concurrent IV administration with IV ß-blockers can
cause severe hypotension
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Adenosine

Indications (When & Why?)
– First drug for narrow-complex PSVT
– May be used diagnostically (after lidocaine)
in wide-complex tachycardias of uncertain
type
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Adenosine

Dose (How?)
– IV Rapid Push
– Initial bolus of 6 mg given rapidly over 1 to 3
seconds followed by normal saline bolus of
20 mL; then elevate the extremity
– Repeat dose of 12 mg in 1 to 2 minutes if
needed
– A third dose of 12 mg may be given in 1 to 2
minutes if needed
57
Adenosine

Precautions (Watch Out!)
– Transient side effects include:
 Facial
Flushing
 Chest pain
 Brief periods of asystole or bradycardia
– Less effective in patients taking
theophyllines
58
Beta Blockers

Indications (When & Why?)
– To convert to normal sinus rhythm or to slow
ventricular response (or both) in
supraventricular tachyarrhythmias (PSVT,
atrial fibrillation, or atrial flutter)
– ß-Blockers are second-line agents after
adenosine, diltiazem, or digoxin
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Beta Blockers

Dosing (How?)
– Metoprolol

5 mg slow IV at 5-minute intervals to a total of 15 mg
– Atenolol


5 mg slow IV (over 5 minutes)
Wait 10 minutes, then give second dose of 5 mg slow IV
(over 5 minutes)
– Propranolol


1 to 3 mg slow IV. Do not exceed 1 mg/min
Repeat after 2 minutes if necessary
60
Beta Blockers

Precautions (Watch Out!)
– Concurrent IV administration with IV calcium
channel blocking agents like verapamil or diltiazem
can cause severe hypotension
– Avoid in bronchospastic diseases, cardiac failure, or
severe abnormalities in cardiac conduction
– Monitor cardiac and pulmonary status during
administration
61
ACE Inhibitors

Indications (When & Why?)
– Reduce mortality & improve LV dysfunction
in post AMI patients
– Help prevent adverse LV remodeling, delay
progression of heart failure, and decrease
sudden death & recurrent MI
Acute Coronary Syndromes
62
Amiodarone

Indications (When & Why?)
– Powerful antiarrhythmic with substantial
toxicity, especially in the long term
– Exceptionally long half life.
– Actually works to one degree or another in
ALL of the VW classifications of
antiarrhythmics.
– Most prominently K+ channel blocker
63
Amiodarone

Dosing (How?)
– Stable Wide-Complex Tachycardias
 Rapid
Infusion
– 150 mg IV over 10 minutes (15 mg/min)
– May repeat
 Slow Infusion
– 360 mg IV over 6 hours (1 mg/min)
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Amiodarone

Dosing (How?)
– Maintenance Infusion
 540
mg IV over 18 hours (0.5 mg/min)
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Amiodarone

Precautions (Watch Out!)
– May produce vasodilation
– May have negative inotropic effects
– May prolong QT Interval
 DO
NOT administer with other drugs that may
prolong QT Interval (Procainamide)
– Terminal elimination
 Half-life
lasts up to 40 days
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Amiodarone

Precautions (Watch Out!)
– Contraindicated in:
 Second
or third degree A-V block
 Severe bradycardia
 Pregnancy
 CHF
 Hypokalaemia
 Liver dysfunction
67
Drugs used in
Overdoses
68
Calcium Chloride

Indications (When & Why?)
– As an antidote for toxic effects of calcium
channel blocker overdose
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Calcium Chloride

Dosing (How?)
– 8 to 16 mg/kg (usually 5 to 10 mL) IV for
hyperkalemia and calcium channel blocker
overdose
70
Naloxone
Hydrochloride

Indications (When & Why?)
– Respiratory and neurologic depression due
to opiate intoxication unresponsive to
oxygen and hyperventilation
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Naloxone
Hydrochloride

Dosing (How?)
– 0.4 to 2 mg IVP every 2 minutes
– Use higher doses for complete narcotic
reversal
– Can administer up to 10 mg in a short time
(10 minutes)
72
Naloxone
Hydrochloride

Precautions (Watch Out!)
– May cause opiate withdrawal
– Effects may not outlast effects of narcotics
– Monitor for recurrent respiratory depression
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Review of
Infusions
74
Dobutamine

Indications (When & Why?)
– Consider for pump problems (congestive
heart failure, pulmonary congestion) with
systolic blood pressure of 80 to 100 mm Hg
and no signs of shock
– Increases Inotropy
– Utility of this medication in EMS is
debatable.
75
Dobutamine

Dosing (How?)
– Usual infusion rate is 2 to 20 µg/kg per
minute
– Titrate so heart rate does not increase by
more than 10% of baseline
– Hemodynamic monitoring is recommended
for optimal use
76
Dobutamine

Precautions (Watch Out!)
– Avoid when systolic blood pressure <100
mm Hg with signs of shock
– May cause tachyarrhythmias, fluctuations in
blood pressure, headache, and nausea
– DO NOT mix with sodium bicarbonate
Review of Infusions
77
Dopamine

Indications (When & Why?)
– Second drug for symptomatic bradycardia
(after atropine)
– Use for hypotension (systolic BP 70 to 100
mm Hg) with S/S of shock
Review of Infusions
78
Dopamine

Dosing (How?)
– IV Infusions (Titrate to Effect)
 “Vasopressor
Dose"
– 10 to 20 µg/kg per minute
Review of Infusions
79
Dopamine

Precautions (Watch Out!)
– May use in patients with hypovolemia but only after
volume replacement
– May cause tachyarrhythmias, excessive
vasoconstriction
– DO NOT mix with sodium bicarbonate
Review of Infusions
80
Norepinephrine

Indications (When & Why?)
– For severe cardiogenic shock and
hemodynamic significant hypotension
(systolic blood pressure < 70 mm/Hg) with
low total peripheral resistance
– This is an agent of last resort for
management of ischemic heart disease and
shock
Review of Infusions
81
Norepinephrine

Dosing (How?)
– 0.5 to 1 mcg/min titrated to improve blood
pressure (up to 30 mcg/min)
– DO NOT administer is same IV line as
alkaline infusions
– Poison/drug-induced hypotension may
higher doses to achieve adequate perfusion
Review of Infusions
82
Norepinephrine

Precautions (Watch Out!)
– Increases myocardial oxygen requirements
– May induce arrhythmias
– Extravasation causes tissue necrosis
Review of Infusions
83
Thank You!
84
ACE Inhibitors

Indications (When & Why?)
– Suspected MI & ST elevation in 2 or more
anterior leads
– Hypertension
– Clinical signs of AMI with LV dysfunction
– LV ejection fraction <40%
Acute Coronary Syndromes
85
ACE Inhibitors

Indications (When & Why?)
– Generally not started in the ED but within
first 24 hours after:
 Fibrinolytic
therapy has been completed
 Blood pressure has stabilized
Acute Coronary Syndromes
86
Beta Blockers

Dosing (How?)
– Metoprolol

5 mg slow IV at 5-minute intervals to a total of 15 mg
– Atenolol


5 mg slow IV (over 5 minutes)
Wait 10 minutes, then give second dose of 5 mg slow IV
(over 5 minutes)
– Propranolol


1 to 3 mg slow IV. Do not exceed 1 mg/min
Repeat after 2 minutes if necessary
Acute Coronary Syndromes
87
ACE Inhibitors

Dosing (How?)
– Should start with low-dose oral
administration (with possible IV doses for
some preparations) and increase steadily to
achieve a full dose within 24 to 48 hours
Acute Coronary Syndromes
88
ACE Inhibitors

Dosing (How?)
– Enalapril
 2.5
mg PO titrated to 20 mg BID
 IV dosing of 1.25 mg IV over 5 minutes, then
1.25 to 5 mg IV every six hours
– Captopril
 Start
with 6.25 mg PO
 Advance to 25 mg TID, then to 50 mg TID as
tolerated
Acute Coronary Syndromes
89
ACE Inhibitors

Dosing (How?)
– Lisinopril (AMI dose)
5
mg within 24 hours onset of symptoms
 10 mg after 24 hours, then 10 mg after 48 hours,
then 10 mg PO daily for six weeks
– Ramipril
 Start
with single dose of 2.5 mg PO
 Titrate to 5 mg PO BID as tolerated
Acute Coronary Syndromes
90
Beta Blockers

Dosing (How?)
– Esmolol


0.5 mg/kg over 1 minute, followed by continuous infusion at
0.05 mg/kg/min
Titrate to effect, Esmolol has a short half-life (<10 minutes)
– Labetalol


10 mg labetalol IV push over 1 to 2 minutes
May repeat or double labetalol every 10 minutes to a
maximum dose of 150 mg, or give initial dose as a bolus,
then start labetalol infusion 2 to 8 µg/min
91
Beta Blockers

Dosing (How?)
– Esmolol


0.5 mg/kg over 1 minute, followed by continuous infusion at
0.05 mg/kg/min
Titrate to effect, Esmolol has a short half-life (<10 minutes)
– Labetalol


10 mg labetalol IV push over 1 to 2 minutes
May repeat or double labetalol every 10 minutes to a
maximum dose of 150 mg, or give initial dose as a bolus,
then start labetalol infusion 2 to 8 µg/min
Acute Coronary Syndromes
92