Chapter 3 Flashcards
1
Q
What can result from blockage of the RCA?
A
Inferior wall MI and/or disturbances in AV nodal conductions
2
Q
Occlusion of what artery is called the widow maker?
A
Occlusion of the left main coronary artery
3
Q
What can result from blockage of the circumflex artery?
A
lateral wall MI
in some patients, occlusion of the circumflex can also lead to a posterior wall MI
4
Q
increased blood concentration of what electrolytes will decrease automaticity?
A
Decreased sodium, potassium and calcium
5
Q
decreased concentrations of what electrolytes will increased automaticity?
A
K+ and Ca2+
6
Q
What is the term that describes the ability of cardiac muscle cells to respond to an external stimulus, such as that from a chemical, mechanical or electrical source?
A
Excitability (irritability)
7
Q
What is the term that describes the ability of a cardiac cell to receive and electrical impulse and conduct it to an adjoining cardiac cell?
A
Conductivity
Via intercalated disks
8
Q
What’s the term that describes the ability of myocardial cells to shorten, thereby causing cardiac muscle contraction, in response to electrical stimuli
A
Contractility
9
Q
The state when the inside of a cell is more negative than the outside of the cell
A
Polarized state
10
Q
What causes depolarization
A
movement of sodium into the cell
11
Q
Where does depolarization occur in the heart
A
depolarization proceeds from innermost later of the heart to the outermost layer (endocardium –> Epicardium)
12
Q
What on the ECG represents ventricular repolarization?
A
ST segment and T wave
13
Q
what occurs after the relative refractory period and allows a weaker-than-normal stimulus to cause cardiac cells to depolarize?
A
Supranormal period
seen at the end of the T wave
- because the cell is more excitable than normal, dysrhythmias can develop during this period
14
Q
What’s the primary pacemaker and what’s its intrinsic rate?
A
SA node, 60-100 bpm
15
Q
What are the bpm of the different pacemakers?
A
SA node: 60 - 100 bpm
AV junction: 40 - 60 bpm
Purkinje fibers: 20 - 40 bpm
16
Q
What heart surface is viewed from the three standard limb leads?
A
Lead I - lateral heart
Leads II and III - inferior heart
17
Q
What heart surface is viewed from each of the augmented leads?
A
aVR - non
aVL - lateral
aVF - inferior
18
Q
Where is lead V1 placed?
A
4th intercostal space on the R next to the sternum
19
Q
Where is lead V2 placed?
A
4th intercostal space on the L next to the sternum
20
Q
Where is lead V4 placed?
A
left midclavicular line in the 5th intercostal space
21
Q
If time doesn’t permit obtaining all of the R chest leads, which is the lead of choice?
A
V4R
22
Q
What leads view the inferior surface of the heart?
A
II, III, aVF
23
Q
What leads view the septal surface of the heart?
A
V1, V2
24
Q
What leads view the anterior surface of the heart?
A
V3, V4
25
What leads view the lateral surface of the heart?
I, aVL, V5, V6
26
how much time does a 1mm box stand for?
0.04 second
27
how much time does a large box stand for?
0.2 seconds (contains 5 x 1 mm boxes)
28
how many mV does the height of one block correspond to?
0.1 mV for each 1 mm box
29
What signifies a pathological Q wave?
Abnormal Q waves are more than .04 s in duration or more than one-third the height of the following R wave in that lead
30
What length of WRS time signifies and incomplete or complete BBB?
normal - 0.11 s
incomplete - .10 - .12
complete - more than or equal to .12
31
What causes a wide QRS?
When an electrical impulse doesn't follow the normal ventricular conduction pathway it takes longer to depolarize the myocardium = delay in conduction through the ventricle
32
What interval represents total ventricular activity?
QT interval
33
What's the normal length of a PR interval?
0.12 to 0.20 seconds
34
What is the normal rate?
60-100 bpm
35
In respiratory sinus arrhythmia, when does HR increase and when does it decrease?
HR increase during inspiration
| HR decrease during expiration
36
when would you use synchronized cardioversion in tachycardia?
When the patient is unstable and they have a pulse and serious signs and symptoms due to the tachycardia
37
what rhythms are included in supraventricular arrhythmias?
Rhythms that being in the SA node, atrial tissue or the AV junction
38
What heart rate is considered tachycardic in adults, children and infants?
Adults 101 - 180bpm
Children >160 bpm
infants >200 bpm
39
How should you treat a tachycardia?
Never shock a sinus tachycardia! treat the cause of the tachycardia
40
What are the 3 types of supraventricular tachycardias?
1. Atrial tachycardia
2. AV nodal reentrant tachycardia (AVNRT)
3. AV reentrant tachycardia (AVRT)
41
What can cause palpitations that occur regularly and with a sudden onset and end?
AVNRT or AVRT
42
What can cause irregular palpitations?
premature complexes, atrial fibrillation, or multifocal atrial tachycardia
43
What is considered a sustained rhythm?
When it lasts more than 30 seconds
44
Whats the DOC for patients with atrial tachycardia when vagal maneuvers don't work?
Adenosine
| do not use in patietns with severe asthma
45
What type of CCB are diltiazem and verapamil?
non-dihydropyridines
46
What type of CCB are nifedipine and amlodipine?
Dihydropyridines
47
CCBs that affect the peripheral vasculature resulting in peripheral vasodilation with little or no effect on the SA or AV nodes
Dihydropyridines
48
CCBs that decrease HR and myocardial contractility, slow conduction through the AV node and have some peripheral arteral dilatory effects as well.
Non-dihydropyridines
49
What are the major adverse effects of CCBs?
hypotension, worsening heart failure, bradycardia, and AV block
50
what's the most common type of supraventricular tachycardia?
AVNRT
51
If you have a stable but symptomatic patient with AVNRT that is not responding to vagal maneuvers, what treatment should you use?
Adenosine
52
If you have an unstable symptomatic patient with AVNRT how should you treat them?
oxygen, IV access and sedation (if the patient is awake and time permits), followed by synchronized cardioversion
53
What is a regular, narrow-QRS tachycardia that starts or ends suddenly called?
Paroxysmal supraventricular tachycardia
54
What is called when rhythms originate from about the ventricles but in which the impulse travels via a pathway other than the AV node and bundle of His?
pre-excitation
55
What pre-excitation syndromes are prone to Atrioventricular reentrant tachycardia?
Wolff-Parkinson-White syndrome and Lown-Ganong-Levine syndrome
56
what is the accessory pathway in WPW syndrome?
Kent bundle
| Connects the atria directly to the ventricles
57
What is the accessory pathway in Lown-Ganogn-Levine syndrome?
James bundle
Connects the atria directly to the lower portion of the AV node (bypassing the AV node)
58
What arrhythmia is associated with a short PR interval, a delta wave and widening of the QRS?
WPW syndrome
59
What is a common cause of junctional tachycardia?
Digitalis toxicity
60
What duration of the QRS is considered a wide-QRS tachycardia?
0.12 s or more
61
What is the first drug you should give a stable patient with a regular rhythm and a monomorphic wide QRS tachycardia but you are unsure of the origin?
Adenosine
62
if the rhythm is Ventricular Tachycardia, what effect will Adenosine have?
No effect in most cases
63
If a wide-QRS rhythm is actually a SVT with aberrancy, what will adenosine administration do?
Adenosine will usually result in transient slowing or conversion to a sinus rhythm
64
What pharmacological therapies can you use for pharmacologic termination of a stable wide-QRS tachycardia that is most likely VT?
Procainamide, Amiodarone, or Sotalol
These drugs are considered first line antiarrhythmics for monomorphic VT
65
If a patient presents with serious signs and symptoms caused by a tachycardia, should you make a specific diagnosis of the origin of the tachycardia?
No, the diagnosis of the origin of the tachycardia is irrelevant, the patient requires immediate electrical therapy (synchronized cardioversion)
66
What's the most common cause of delayed ventricular conduction?
BBB
67
What are the criteria for a Right BBB?
- The QRS must have an abnormal duration
- The QRS complex must arise as the result of supraventricular activity (excluding ventricular beats and paced ventricular complexes)
- Look at lead V1
- Check the last .04 seconds of the QRS and it should be positive for a R BBB
68
What are the criteria for a Left BBB?
- The QRS must have an abnormal duration
- The QRS complex must arise as the result of supraventricular activity (excluding ventricular beats and paced ventricular complexes)
- Look at lead V1
- Check the last .04 seconds of the QRS and it should be negative for a L BBB
69
What is the rhythm when three or more ventricular beats occur in a row at a rate of 41 - 100 beats/min
Accelerated idioventricular rhythm
70
When do you see an accelerated idioventricular rhythm?
It occurs most often in the setting of acute MI, most often during the first 12 hours. particularly common after successful reperfusion therapy
71
What is seen with 3 or more premature ventricular complexes occurring in immediate succession at a rate greater than 100 bpm?
Ventricular tachycardia
72
A rapid, wide QRS rhythm associated with pulselessness, shock or heart failure should be presumed to be what until proven otherwise?
Ventricular tachycardia
73
do patients with sustained monomorphic VT often have underlying heart disease?
Yes, particularly myocardial ischemia. It rarely occurs in patients without underlying heart disease
74
T or F: sustained VT does not always produce signs of hemodynamic instability
TRUE
75
How do you treat a pulseless patient with VT?
Cardiopulmonary resuscitation (CPR) and defibrillation
76
How should you treat patients with stable but symptomatic VT?
- Oxygen (if indicated)
- IV access
- Ventricular antiarrhythmics like procainamide, sotalol or amiodarone
note: don't use procainamide in patients with prolonged QT or signs of heart failure. Don't use sotalol in patients with prolonged QT interval
77
How should you treat patients with unstable VT?
- oxygen
- IV access
- sedation (if awake and time permits) followed by synchronized cardioversion
78
What rhythms are considered irregular tachycardias?
Multifocal atrial tachycardia
Atrial flutter
Atrial Fibrillation
Polymorphic ventricular tachycardia
79
What is the name for when you have a wandering atrial pacemaker where the size, shape and direction of the P waves vary and the rate is greater than 100 bpm?
Multifocal atrial tachycardia
80
Patients who experience atrial fibrillation are at increased risk of having what?
A stroke
81
What is the typical rate that is seen with a polymorphic ventricular tachycardia?
150 - 300 bpm, typically 200-250bpm
82
How long is the QT interval in torsades de pointes?
more than .45 s, often .5 s or more
83
what are some acquired causes of torsades de pointes?
an antiarrhythmic drug
hypokalemia
typically associated with bradycardia
84
what type of polymorphic ventricular tachycardia is triggered by stress or exercise and occurs in the absence of QT prolongation or structural heart disease?
Catecholaminergic PMVT
85
what type of polymorphic ventricular tachycardia is associated with an EKG pattern consisting of a RBB-like conduction and ST elevation in the right chest leads without evidence of QT prolongation or structural heart disease?
Brugada syndrome
86
T or F: A patient with sustained PMVT is rarely hemodynamically stable
True
87
If a patient is symptomatic as a result of a polymorphic ventricular tachycardia, how should you treat them?
- Treat ischemia if it's present
- correct electrolyte abnormalities
- discontinue any medications that the patient may be taking that prolong the QT interval
88
If a patient is stable with a polymorphic ventricular tachycardia, how should you treat them?
Use IV amiodarone (if the QT interval is normal), magnesium, or beta blockers
89
If a patient is unstable or has no pulse with a polymorphic ventricular tachycardia, how should you treat them?
defibrillation as you would for VF
90
Can you use amiodarone, procainamide or sotalol with torsades de pointes?
No - these drugs prolong the QT interval
91
What's the equation for cardiac output?
CO = stroke volume x heart rate
92
what is an absolute bradycardia?
a heart rate less than 60 bpm
93
what is a relative bradycardia?
the heart rate may be more than 60 bpm
94
At what heart rate with bradycardia do patients become symptomatic ?
less than 50 bpm
95
what should the initial treatment of any patient with a symptomatic bradycardia be?
support of airway and breathing
96
What is the first line drug recommended for symptomatic bradycardia?
Atropine
Note that Atropine won't work for certain bradycardias like complete AV blocks or wide-QRS AV blocks
97
What are some interventions that can be used for bradycardia?
Atropine (1st line)
| others: epinephrine, dopamine, isoproterenol IV infusions or transcutaneous pacing
98
What rate is considered a sinus bradycardia?
less than 60 bpm
99
What rhythm can result from the following: adults while sleeping, well conditioned athletes, some younger people while at rest, some MIs, with stimulation of the vagus nerve (coughing, vomiting, straining/valsalva, carotic sinus pressure, cold water to the face), hyperkalemia, hypoxia, hypothermia
Sinus bradycardia
100
If a patient is symptomatic with sinus bradycardia, what would your initial treatment include?
Supplemental oxygen if needed, starting an IV, and giving IV atropine
101
What's the intrinsic rate of the AV junction?
40-60 bpm
102
what type of acute coronary syndrome can commonly cause a junctional rhythm ?
inferior wall MI
103
What is a substance that affects the heart rate called?
a Chronotrope
Positive chronotrope: increases heart rate
104
What is a substance that affects the AV conduction velocity called?
a Dromotrope
Positive dromotrope: increased AV conduction velocity
105
What is a substance called that affects myocardial contractility?
an Inotrope
Positive inotrope: increased force of contraction
106
Where are alpha 1 receptors found and what is the result when they are stimulated?
Alpha 1 are found: in the eyes, blood vessels, bladder and male reproductive organs
Stimulation results in constriction
107
Where are alpha 2 receptors found and what is the result when they are stimulated?
Alpha 2 receptors are found: in parts of the digestive system and on presynaptic nerve terminals in the peripheral nervous system
Stimulation results in decreased secretions, decreased peristalsis and suppression of norepinephrine release
108
Where are beta 1 receptors found and what is the result when they are stimulated?
Beta 1 receptors are found: in the heart and kidneys.
stimulation results in increased heart rate and increased contractility. in the kidneys it results in renin release in the blood leading to vasoconstriction (via angiotensin)
109
Where are Beta 2 receptors found and what is the result when they are stimulated?
Beta 2 receptors are found in the arterioles of the heart, lungs and skeletal muscles.
Stimulation results in smooth muscle dilation in the bronchi
110
Where are dopamine receptors found and what is the result when they are stimulated?
Dopamine receptors are found in the renal, mesenteric and visceral blood vessels
Stimulation results in dilation
111
How do you determine the infusion rate for dopamine?
Dopamine depends on the patients weight and its dose range is 5-10 mcg/kg/min
112
How do you determine the infusion rate for isoproterenol?
Isoproterenol infusion is NOT based on the patients weight and it's infused at 2-10 mcg/min
113
how do you determine the infusion rate for epinephrine?
in SYMPTOMATIC bradycardia, epinephrine infusion is infused at a dose range of 2-10 mcg/min
In post-cardiac arrest care, epinephrine is infused at a rate of 0.1 - 0.5 mcg/kg/min
114
What is called when three or more ventricular beats occur in a row at a rate of 20-40 bpm?
A ventricular escape or idioventricular rhythm
115
Can you use lidocaine when treating a ventricular escape rhythm?
No! lidocaine should be avoided because it can abolish ventricular activity possible causing asystole in a patient with a ventricular escape rhythm
116
What is it called when a patient with a ventricular escape rhythm is not breathing and has no pulse despite the appearance of organized electrical activity on the EKG?
pulseless electrical activity
117
What is seen in a first-degree AV block?
PR is prolonged more than 0.2 seconds but it's constant
Note that 1st degree AV block is not a dysrhythmia itself, it's a condition that describes the consistent prolonged PR interval seen on EKG - the impulses from the SA node to the ventricles is DELAYED not blocked
118
Give a run down of what you see with the P waves in the different AV blocks?
1st degree AV block --> All P waves are conducted but delayed
2nd degree AV block --> Some P waves are conducted, and others are blocked
3rd degree AV block --> No P waves are conducted
119
Where is the site of block in second degree AV block type 1?
AV node
120
where is the site of block in second degree AV block type 2?
the bundle of His or more commonly at the bundle branches
121
What is second degree AV block type 1 also known as?
Mobitz type 1 or Wenckebach
122
What is seen with second degree AV block type 1?
progressive lengthening of the PR interval with each cycle until a p wave appears without a QRS complex.
note that the atrial rhythm (P's) are regular, it's the ventricular rhythm that is irregular
123
what causes second degree AV block type 1?
The RCA supplies the AV node so RCA occlusions can lead to AV block at the AV node
124
what causes second degree AV block type 2?
Bundle branches receive their primary blood supply from the LCA so disease of the LCA or an anterior MI can be seen. AV block type II can also be seen with acute myocarditis or other organic heart diseases
Note that 2nd degree AV block type 2 is more serious than 1st degree and it can progress to 3rd degree AV block
125
T or F - second degree AV block type II is usually an indication for a permanent pacemaker
True
126
What AV block has compete block in conduction of impulses between the atria and the ventricles?
3rd degree AV block
127
If monomorphic or polymorphic ventricular tachycardia present without a pulse, how do you treat them?
You should treat them as ventricular fibrillation
128
what is seen with ventricular fibrillation?
The ventricular muscle quivers, therefore there is no effective myocardial contraction and no pulse
129
what are the priorities of care in cardiac arrest due to pulseless VT or VF?
High quality CPR and defibrillation
130
why is epinephrine given in cardiac arrest?
Primarily for its vasoconstricting (alpha-adrenergic) properties
Vasoconstriction helps increase coronary and cerebral perfusion pressures
131
What are the adverse effects of epinephrine?
myocardial oxygen consumption and necrosis, post-resuscitation myocardial dysfunction and ventricular dysfunction
132
What medications are absorbed via the trachea?
Naloxone, atropine, vasopressin, epinephrine, and lidocaine
tracheal route is NOT preferred but recommended dose would be 2 - 2.5 times the IV dose
133
If pulseless VT/VF continues despite CPR, defibrillation and administration of a vasopressor what antiarrhythmic should you give?
Amiodarone - improves the rate of return of spontaneous circulation
lidocaine may be considered if amiodarone is not available
134
what is the rhythm called when you have a total absence of ventricular electrical activity?
asystole or ventricular asystole
135
what are the possible treatable causes of cardiac arrest?
PATCH-4-MD, 5Hs, 5Ts
136
what should you do before you start CPR in a patient with asystole?
see asystole on a cardiac monitor, confirm that the patient is unresponsive and has no pulse then begin CPR
Additional care includes establishing vascular access, considering the possible causes of the arrest, administering epinephrine and possibly inserting an advanced airway
137
what is called when organized electrical activity (other than VT) is observed on the cardiac monitor, but the patient is unresponsive and not breathing and a pulse can't be felt?
Pulseless electrical activity
138
how do you treat PEA?
High-quality CPR, establishing vascular access, the administration of epinephrine and an aggressive search for possible causes of the situation and the possible insertion of an advanced airway
139
A resuscitation effort requires coordination of what four critical tasks?
1. chest compressions
2. airway management
3. ECG monitoring and defibrillation
4. vascular access and drug administration
140
how are IV bolus medications given?
IV bolus medications are followed with a 20 mL fluid flush and the brief elevation of the affected extremity
141
What are the seven phases of the phase response of code organization?
```
phase 1 - anticipation
phase 2 - entry
phase 3 - resuscitation
phase 4 - maintenance
phase 5 - family notification
phase 6 - transfer
phase 7 - critique
```
142
What can be helpful in letting you know that there has been a return of spontaneous circulation?
existence of a waveform on the pulse oximeter
143
If no IV is in place at the time of cardiac arrest, what do you do?
start a peripheral IV with a large gauge catheter (without interrupting CPR)
the antecubital or external jugular veins are preferred.
144
What are the preferred IV solutions to use in cardiac arrest?
Normal saline or lactated ringer's
glucose containing solutions should be avoided unless theres documented hypoglycemia
145
If peripheral IV attempts are unsuccessful during cardiac arrest what should you do?
Intraosseous access should be attempted before trying a central line
146
When should drugs be given during cardiac arrest?
During brief pauses for rhythm checks and then followed with a 20 ml flush of IV fluid and brief elevation of the affected extremity.
the drug is then circulated when CPR is continued
147
how do you know you're in the maintenance phase (phase 4) of the phase response of code organization?
a spontaneous pulse has returned or the patients vital signs have stabilized
148
what does post-cardiac arrest care focus on?
cardioprotective and neuroprotective interventions
149
why should you avoid hyperventilation?
hyperventilation increases the intrathoracic pressure and lowers cardiac output
150
why should you avoid hypoventilation?
hypoventilation can contribute to hypoxia and hypercarbia
151
why is it important to maintain temperature regulation after a cardiac arrest?
for each degree Celsius higher than 37C the risk of an unfavorable neurologic recovery increases
152
portion of the ECG tracing between the QRS complex and the T wave
PR interval
153
portion of the ECG tracing between the end of the T wave and the beginning of the following P wave
TP segment
154
represents atrial depolarization and the spread of an electrical impulse through the left and right atria
P wave
155
represents the spread of an electrical impulse through the ventricles (ventricular depolarization)
QRS complex
156
first positive deflection in the QRS complex
R wave
157
Represents total ventricular activity - the time from ventricular depolarization (stimulation) to repolarization (recovery)
QT interval
158
normally measures 0.12 to 0.2 s in adults
PR interval
159
This is ALWAYS negative
S wave
160
horizontal line between the end of the p wave and the beginning of the QRS complex
PR segment
161
ventricular rhythm may be regular or irregular, waveforms resembling teeth of a saw or picket fence before QRS
Atrial flutter
162
Regular ventricular rate between 150 - 250 bpm; narrow QRS
AV nodal reentrant tachycardia
163
More P waves than QRSs, P waves occur regularly, irregular ventricular rhythm, lengthening PR intervals, QRS usually narrow
Second-degree AV block type 1
164
absent P waves, wide QRS, ventricular rate 40 bpm or less
ventricular escape rhythm
165
Rapid rhythm in which the QRS complex is wide and usually regular; QRS complexes are of same shape and amplitude
monomorphic ventricular tachycardia
166
irregularly irregular ventricular rhythm, no identifiable P waves
atrial fibrillation
167
more P waves than QRSs, P waves occur regularly, regular ventricular rhythm, no pattern to PR intervals, QRS narrow or wide
third-degree AV block
168
irregularly irregular rhythm with no normal looking waveforms; chaotic deflections vary in shape and amplitude
ventricular fibrillation
169
one upright P wave before each QRS, ventricular rate 101 - 180 bpm
sinus tachycardia
170
more P waves than QRSs, P waves occur regularly, irregular ventricular rhythm, constant PR intervals, QRS usually wide
second degree AV block Type 2
171
rapid rhythm in which the QRS complexes are wide and appear to twist from upright to negative or negative to upright and back
polymorphic ventricular tachycardia
172
Initial dosage of adenosine IV
6 mg rapid IV push
173
initial dosage of verapamil IV
2.5 to 5 mg slow IV push
174
atropine dose IV
0.5 mg every 3 to 5 minutes, total dose 3 mg
175
dosage of vasopressin IV in cardiac arrest
40 units
176
loading dose of IV amiodarone for indications other than cardiac arrest
150 mg over 10 min
177
Dopamine IV infusion dosage
2 to 10 mcg/kg/min
178
Initial IV/IO dosage of amiodarone in cardiac arrest
300 mg
179
Dosage of IV magnesium sulfate for torsades de pointes
1 to 2 g
180
Epinephrine IV dosage in cardiac arrest
1 mg every 3 to 5 min
181
Initial dose of diltiazem IV
0.25 mg/kg IV bolus over 2 min
182
dosage of procainamide
20 to 50 mg/min; total dose 17 mg/kg
183
epinephrine IV infusion dosage
2 to 10 mcg/min
184
initial IV/IO dosage of lidocaine
1 to 1.5 mg/kg
185
what's the intrinsic rate of the AV junction?
40 - 60 bpm
186
atrial fibrillation, atrial flutter and polymorphic ventricular tachycardia are examples of what?
irregular tachycardias
187
What is the R wave?
The first positive defection after the P wave
188
what's the most common type of paroxysmal supraventriular tachycardia?
AV nodal reentrant tachycardia
189
What are the main branches of the LCA?
circumflex and anterior descending arteries
190
What are three or more PVS occurring in a row at a rate of more than 100/min called?
A run of ventricular tachycardia
191
What medication can you give as an IV bolus in pulseless electrical activity, pulseless ventricular tachycardia and asystole?
Epinephrine
192
What's the recommended treatment in a patient with monomorphic ventricular tachycardia?
ABCs, O2, IV, and procainamide 20-50 mg/min IV
193
A rapid wide WRS rhythm associated with pulselessness, shock or heart failure should be assumed to be what?
Ventricular tachycardia
194
What's the correct IV dose of atropine in the management of symptomatic bradycardia?
0.5 mg every 3 to 5 min with a maximum dose of 3 mg
195
what's the lidocaine dosing in pulseless VT/VF ?
initial dose is 1 to 1..5 mg/kg IV push; repeat doses of 0.5 to0.75 mg/kg IV push may be given at 5 to 10 minute intervals to a maximum dose of 3 mg/kg
196
when administering procainamide, what is the maximum dose and what is the maintenance dose?
the maximum dose is 17 mg/kg and the maintenance infusion is 1 to 4 mg/min
197
When do you give an IV bolus of epinephrine?
An IV bolus of epinephrine is indicated in cardiac arrest (PEA, asystole, pulseless VT and VF)
Epinephrine is not given IV bolus to patients who have a pulse
although epinephrine may be given to patients for symptomatic bradycardia, it is given as an IV infusion, not an IV bolus
198
what is the preferred antiarrhythmic in patients with cardiac arrest due to pulseless VT/VF?
amiodarone
| lidocaine when amiodarone is not available
