ECG Monitoring Flashcards
1
Q
Review practice standards.
A
Slide 2
2
Q
On a rhythm strip how many seconds is a small box?
A
0.04 seconds
3
Q
On a rhythm strip how many seconds is a medium (5 small box) box?
A
0.20 seconds
4
Q
What is the height of the medium box (5 small boxes)?
A
0.5 mV
5
Q
How many seconds makes a true strip?
A
6 seconds
6
Q
Interpret rhythm strip image.
A
Slide 6
7
Q
What are the difference waves that make up an ECG?
A
represent the sequence of depolarization and repolarization of the atria and ventricles
8
Q
The ECG is recorded at a speed of _______.
A
25 mm/sec
9
Q
Each small 1-mm square represents ________ in time and _______
A
0.04 sec (40 msec), 0.1 mV in voltage.
10
Q
Identify the P wave. What does it represent?
A
Represents depolarization of the atria as the electrical impulse moves from the SA node to the atria.
11
Q
How can the atrial rate be calculated?
A
by determining the time interval between the p waves.
12
Q
Identify the P wave. What is the normal P wave distance in seconds?
A
Normal 0.08 - 0.10s.
13
Q
Identify the P-R interval. What occurs in the P-R interval?
A
The period of time from the onset of the P wave to the beginning of the QRS complex. The PR Interval represents the time between the onset of atrial depolarization and the onset of ventricular depolarization.
14
Q
Identify the P-R interval. What is the normal PR interval?
A
Normal 0.12 – 0.20s
15
Q
Identify the QRS complex. What is occuring during this?
A
Represents ventricular depolarization
16
Q
Identify the QRS complex. What is the normal length of the QRS complex?
A
Normal 0.06 – 0.10s.
17
Q
How is the ventricular rate determined?
A
can be calculated by determining the time interval between QRS complexes
18
Q
What effects the shape of the QRS complex?
A
changes depending on which leads are being viewed.
19
Q
Identify the ST segment. What is occuring here?
A
The isoelectric period following the QRS complex. This is the time at which the entire ventricle is depolarized.
20
Q
Identify the T wave. What is occuring here?
A
Represents ventricular repolarization, which is longer in duration than depolarization
21
Q
What is a U wave? What does it represent?
A
Sometimes a small positive U wave may be seen following the T wave (not shown). This wave represents the last remnants of ventricular repolarization
22
Q
Identify the QT interval. What is occuring here?
A
Represents the time for both ventricular depolarization and repolarization to occur.
23
Q
What effect does high heart rates have on the QT interval?
A
ventricular action potentials shorten in duration, which decreases the Q-T interval.
24
Q
What is true about the Q-T interval in clinical practice?
A
In practice, the Q-T interval is expressed as a “corrected Q-T (QTc)” by taking the Q-T interval and dividing it by the square root of the R-R interval (interval between ventricular depolarizations
25
What is the correct Q-T (QTC) allow for assessment of?
This allows an assessment of the Q-T interval that is independent of heart rate
26
What is the normal corrected Q-Tc intervals?
are less than 0.44 seconds.
27
What is the J point?
denotes the junction of the QRS complex and the ST segment on ECG marking the end of depolarization and beginning of repolarization
28
Where does repolarization phase start?
•at the junction, or j point and continues until the T wave
29
What is the location of the ST segment?
The ST segment is normally at or near the baseline
30
What are the six steps to rhythm strip interpretation?
1. Is the overall rhythm regular or irregular
2. What is the atrial and ventricular heart rate (HR)
3. What is the appearance of the P wave?
4. Are the P-R intervals of normal duration and are they fixed?
5. Based upon the response to question four, it can be determined if a relationship exists between the p wave and the adjacent QRS complex
6. What is the appearance of the QRS complex?
31
What needs to be determined if the rhythm is irregular?
is it due to premature beat(s), a delay in the conduction of impulses, or due to an irregular discharge from the primary pacemaker source?
32
What needs to be determined about the appearance of the P wave?
Assess for the origin of atrial depolarization
33
The p wave is __________ in lead 2 when it originates from the SA node.
upright
34
The p wave is __________ in lead 2 when it originates from the A-V node.
Inverted
35
What can be assumed about 1:1 ventricular conduction?
present (p waves conduct adjacent QRS complexes) whenever P-R intervals measure out to be the same (are fixed).
36
What does a narrow QRS complex means?
the beat originated above the ventricles (it was supraventricular
37
What is true about the QRS if it is wide?
it originated in the ventricle (e.g. PVC) or above the ventricle (supraventricular with aberrant ventricular conduction – looks like a PVC but is not
38
Where do junctional rhythms originate?
the SA node is not the origin of the electrical activity of the heart – the atrio-ventricular (AV) node is.
39
What two junctional rhythms will we look at in regard to this course?
There are multiple types of junctional rhythms. We will look at two – junctional escape and junctional tachycardia.
40
What is true regarding the treatment of junctional rhythms?
Treatment for either of these junctional rhythms is rarely needed. If either rhythm is noted, assess patient stability and monitor.
41
Identify the rhythm and if it is regular or irregular.
**Junctional Escape**
* Rhythm: Regular
42
What are the typical rates for junctional escape?
* 40-60bpm
* 60-100bpm (accelerated)
43
Identify the rhythm. Describe the P waves, PR interval and QRS complex characteristics of this rhythm.
**Junctional Escape**
* P waves: Inverted before or after QRS or not visible
* PR Interval: \<0.12sec when inverted p is before QRS
* QRS: 0.04 – 0.10 second
44
Identify this rhythm. What are causes of this rhythm (9)?
**Junctional Escape**
* Healthy athlete at rest
* Related to medications
* Increased parasympathetic tone
* Acute inferior wall MI
* Rheumatic heart disease
* Post-cardiac surgery
* Valvular disease
* SA node disease
* Hypoxia
45
What are some medications that can cause this rhythm (3)?
**Junctional Escape**
* beta blockers
* calcium channel blockers
* digitalis toxicity
46
Identify this rhythm and if it is regular or irregular.
**Junctional Tachycardia**
* Rhythm: Regular
47
What is the characteristic rate of this rhythm?
**Junctional Tachycardia**
* Rate: 101-200bpm
48
Identify this rhythm. Describe the characteristic of the P waves, PR interval and QRS complex with this rhythm.
**Junctional Tachycardia**
* P waves: Inverted before or after QRS or not visible
* PR Interval: \<0.12sec when inverted p is before QRS
* QRS: 0.04 – 0.10 second
49
Identify potential causes of this rhythm. (7)
**Junctional Tachycardia**
* Normal
* Excessive use of caffeine, alcohol or tobacco
* CHF
* Myocardial ischemia or injury
* Hypokalemia, digitalis toxicity
* COPD
50
Identify this rhythm and if it is regular or irregular.
**1st Degree AV Block**
* Regular
* This rhythm looks very similar to NSR. For every p wave, there is a QRS that follows.
51
When does this rhythm occur?
**1st Degree AV Block**
* 1st degree AV block occurs when there is a conduction delay in the AV node.
52
Identify this rhythm. What is the key component to identifying this rhythm?
**1st Degree AV Block**
* The key to identifying this rhythm is the prolonged PR interval. The PR interval for this rhythm is \>0.20 second, but not \>0.40 second (normal PR interval 0.12-0.20 seconds).
53
What are some causes of this rhythm? (6)
**1st Degree AV Block**
* Enhanced vagal tone (for example in athletes)
* Myocarditis
* Acute MI (especially acute inferior MI)
* Electrolyte disturbances
* Medications
54
What are some medications that could cause this rhythm (4)?
**1st Degree AV Block**
* calcium channel blockers
* beta blockers
* cardiac glycosides
* cholinesterase inhibitors
55
Describe the treatment plan for this rhythm.
**1st Degree AV Block**
* identifying any underlying electrolyte imbalances and/or medications that may be causing the conduction delay.
56
Does treatment of this rhythm require hospital admission?
**1st Degree AV Block**
* Typically this arrhythmia does not require hospital admission unless there is an underlying MI
57
Will this rhythm progress to heart block?
**1st Degree AV Block**
* This arrhythmia does not usually have any significant clinical consequences, and except in very rare circumstances, does not progress to complete heart block.
58
Identify this rhythm. Describe the key characteristics that differentiate it from NSR.
**2nd Degree AV Block/Mobitz Type I/Wenkebach**
* There are more p waves than QRS’s
* The PR interval progressively increases until a p wave appears without a QRS afterwards.
* Then the cycle begins again.
* The R to R interval is not regular.
59
What is a way to remember this rhythm?
**2nd Degree AV Block/Mobitz Type I/Wenkebach**
* “Longer, longer, longer drop is found in Wenkebach”
60
What are some causes of this rhythm?
**2nd Degree AV Block/Mobitz Type I/Wenkebach**
* Individuals with increased vagal tone (e.g. athletes and small children)
* Infants and children with structural heart disease (e.g. Tetralogy of Fallot)
* Individuals who have undergone valvular heart surgery, especially mitral valve
* MI
* Medications
61
What is the treatment for unsymptomatic patients with this rhythm?
**2nd Degree AV Block/Mobitz Type I/Wenkebach**
* Unless the patient with this rhythm is symptomatic, it is unlikely that they will need hospitalization.
* Typically patients noted to have this rhythm will be referred to a cardiologist on an outpatient basis.
62
What is the treatment for this rhythm if a MI is the suspected underlying cause?
**2nd Degree AV Block/Mobitz Type I/Wenkebach**
* Patients with suspected underlying myocardial ischemia causing the dysrhythmia should be treated with an appropriate anti-ischemic regimen.
63
What should avoided in a patient with this rhythm?
**2nd Degree AV Block/Mobitz Type I/Wenkebach**
* AV nodal blocking agents (e.g. beta blockers) should be avoided in these patients.
64
What is the treatment for symptomatic patients with this rhythm?
**2nd Degree AV Block/Mobitz Type I/Wenkebach**
* Symptomatic patients may be treated with transcutaneous pacing and/or atropine.
* Extreme caution should be used in administering atropine if patient is suspected to have myocardial ischemia as ventricular dysrhythmias may occur.
65
What are key components to the differientation of this rhythm with NSR?
**2nd Degree AV Block/Mobitz Type II**
* The key to identifying this rhythm is the recognition of unexpected nonconducted atrial impulses.
* Simply put, there are p waves without QRS’s following them.
66
How is this rhythm different from 2nd Degree AV Block/Mobitz Type I?
**2nd Degree AV Block/Mobitz Type II**
* This is different than Type I because the PR interval is consistent (not longer, longer, longer, drop).
67
What is true about the QRS for this rhythm?
**2nd Degree AV Block/Mobitz Type II**
* This rhythm may have either normal or widened QRS complexes.
68
What are the causes of this rhythm?
**2nd Degree AV Block/Mobitz Type II**
* Most commonly caused by an acute MI (especially anterior or inferior)
* Medications (e.g. Beta blockers, calcium channel blockers, amiodarone, digoxin)
* Lyme disease
69
What are some medications that could cause this rhythm? (4)
2nd Degree AV Block/Mobitz Type I/Wenkebach
* Beta blockers
* calcium channel blockers
* amiodarone
* digoxin
70
What are some medication causes of this rhythm?
**2nd Degree AV Block/Mobitz Type II**
* Beta blockers
* calcium channel blockers
* amiodarone
* digoxin
71
What is the pharmacological treatment for this rhythm?
**2nd Degree AV Block/Mobitz Type II**
* Similar to Type I patients, AV nodal medications should be avoided and an anti-ischemic regimen should be initiated if ischemia is suspected.
72
What a mandatory intervention for patients with this rhythm?
**2nd Degree AV Block/Mobitz Type II**
* dysrhythmia whether or not they are symptomatic as this rhythm can rapidly deteriorate into complete heart block.
* The transcutaneous pacer should be tested to ensure capture.
* If capture is not able to be achieved, then insertion of a transvenous pacer is indicated.
73
What is an important consult for this rhythm?
**2nd Degree AV Block/Mobitz Type II**
* An urgent cardiology consult is indicated for patients with symptomatic Type II and asymptomatic patients who are unable to achieve capture with transcutaneous pacing.
74
What is true if you can not distiguish between type I or II AV block?
**2nd Degree AV Block/Mobitz Type II**
* If it is unclear whether the rhythm is Type I or Type II (e.g. where every other beat is dropped) it is safest to assume a Type II block exists and the patient should be admitted.
75
What is this rhythm?
3rd Degree AV Block/Complete Heart Block
* This is a very significant dysrhythmia and should be identified by the caregiver immediately.
76
What are the characteristics of this rhythm? (5)
**3rd Degree AV Block/Complete Heart Block**
* In 3rd degree heart block, there is a complete dissociation of the atria and ventricle.
* Thus, there are more p waves than QRS’s.
* Also, the p waves are in no way related to the QRS’s.
* The PR interval varies greatly (e.g. no pattern, but not regular).
* The QRS complexes may appear normal or wide.
77
What are some causes of this rhythm? (4)
**3rd Degree AV Block/Complete Heart Block**
* Acute MI
* Overdose of medications
* Cardiomyopathy
* Metabolic disturbances (e.g. severe hyperkalemia
78
What are some medications that cause this rhythm?
**3rd Degree AV Block/Complete Heart Block**
* •Overdose of medications (e.g. procainamide, beta blockers, amiodarone, calcium channel blockers, digoxin, etc.)
79
What are the immediate steps that must be taken with this rhythm?
**3nd Degree AV Block/Complete Heart Block**
* Immediately upon recognition of this dysrhythmia ensure the patient is receiving oxygen prn and has a patent IV.
* Take regular blood pressures and maintain continuous cardiac monitoring.
80
What should not be given with this rhythm?
**3rd Degree AV Block/Complete Heart Block**
* AV nodal medications should be withheld and anti-ischemic therapy should be initiated when appropriate.
81
What needs to be applied to the patient with this rhythm?
**3rd Degree AV Block/Complete Heart Block**
* Transcutaneous pacing pads should be applied to the patient and tested
* If capture cannot be achieved with transcutaneous pacing, a transvenous pacemaker should be inserted
82
What is the consult that needs to be done for this 3rd degree/complete heart block ?
**3rd Degree AV Block/Complete Heart Block**
* A cardiology consult is indicated for all patients with this dysrhythmia.
83
What are some side effects of giving atropine to this rhythm?
**3rd Degree AV Block/Complete Heart Block**
* Hemodynamically unstable patients may be treated with atropine, but if the rhythm is a wide complex escape rhythm the atropine is likely to be unsuccessful.
* Similarly, if atropine is administered to a patient with a suspected MI, increased ventricular irritability may occur, leading to ventricular arrhythmias.
84
What needs to happen to patients with this rhythm following stabilization?
**3rd Degree AV Block/Complete Heart Block**
arrangements should be made for permanent pacemaker insertion.
85
Name this rhythm:
A. Normal sinus rhythm with multifocal PVC’s
B.Normal sinus rhythm with unifocal PVC’s
C.Normal sinus rhythm with PAC’s
D.Normal sinus rhythm with PJC’s
ANS: Normal sinus rhythm with multifocal PVC’s (A)
86
Name this rhythm:
A. Normal sinus rhythm with unifocal couplet PVC’s
B.Normal sinus rhythm with multifocal PVC’s
C.Normal sinus rhythm with paced beats (from a pacemaker)
D.Sinus bradycardia with PVC’s
ANS: Normal sinus rhythm with unifocal couplet PVC’s (A)
87
Name this rhythm
A.1st Degree AV Block
B.2nd Degree AV Block, Type I (Wenkebach)
C.2nd Degree AV Block, Type II
D. 3rd Degree AV Block / Complete Heart Block
B. 2nd Degree AV Block, Type I (Wenkebach)
88
Name this rhythm
A.1st Degree AV Block
B.2nd Degree AV Block, Type I (Wenckebach)
C.2nd Degree AV Block, Type II
D.3rd Degree AV Block / Complete Heart Block
D. 3rd Degree AV Block / Complete Heart Block
89
What is Pulseless electrical activity characterized by?
* patient unresponsiveness and a lack of palpable pulses in the presence of organized electrical activity.
90
What is the cause of PEA?
* PEA is caused by the inability of cardiac muscle to generate sufficient force in response to electrical depolarization.
91
What is the treatment for PEAs?
* Patients in PEA should be treated as per the ACLS algorithm, with a focus on identifying the underlying cause(s) of the PEA.
92
What is a way to remember causes for PEA?
H & T's
93
What are the H's that can lead to pulseless electrical activity?
* Hypovolemia
* Hypoxia
* Hydrogen Ion (Acidosis)
* Hypo-/Hyperkalemia
* Hypoglycemia
* Hypothermia
94
What are the T's that cause PEA?
* Toxins
* Tamponade, cardiac
* Tension Pneumothorax
* Thrombosis (coronary or pulmonary)
* Trauma (hypovolemia, increased ICP)
95
What is this rhythm? What type of form is it?
**Torsades de Pointe**
* This arrhythmia is a specific form of ventricular tachycardia with distinct characteristics.
96
What is the hallmark characteristics of this rhythm?
**Torsades de Pointe**
* The hallmark of this arrhythmia is rapid, polymorphic ventricular tachycardia twisting around an isoelectric baseline.
97
When does this rhythm usually occur?
**Torsades de Pointe**
* This is very often seen to occur in patients with a prolonged QT interval and who then prematurely conduct a beat (R on T phenomenon).
98
What are the two types of causes of this rhythm?
Torsades de Pointe
* Congenital prolonged QT syndromes
* Acquired prolonged QT syndromes
99
What are some aquired prolonged QT causes of this rhythm?
**Torsades de Pointe**
* Medications
* Cardiac conditions (e.g. MI, complete heart block)
* Intracranial disorders (e.g. subarachnoid hemorrhage, stroke)
* Nutritional disorders (e.g. anorexia, starvation, celiac disease
100
What are the short term treatment for this rhythm?
Torsades de Pointe
* Defibrillation
* Discontinue the offending medication (if known)
* Magnesium is the drug of choice for suppressing and terminating this arrhythmia.
101
What is true regarding torsades de pointe?
•Although Torsades is often self limiting, it can degenerate into V Fib.
102
What is the MOA of magnesium and torsades de pointe?
•This is achieved by decreasing the influx of calcium.
103
What is the recommended magnesium dose for torsades de pointe?
* Magnesium can be given at 1-2 gm IV initially in 30-60 seconds, which then can be repeated in 5-15 minutes.
* Alternatively, a continuous infusion can be started at a rate of 3-10 mg/min. Magnesium is effective even in patients with normal magnesium levels.
104
Identify the electrolyte abnormality here. What are the characteristics? (4)
Hypokalemia
* U Wave (Early Sign)
* T wave flattened and widened
* T wave inversion
* ST depression
105
What is an early rhythmic sign of this electrolyte abnormality?
**Hypokalemia**
* U Waves
106
What are rhythms usually associated with this electrolyte disturbances?
**Hypokalemia**
* PVC’s, atrial or nodal tachycardia, ventricular tachycardia, ventricular fibrillation
107
What T wave changes associated with hyperkalemia?
* T waves narrowed and peaked
* Early sign (K+ of 6-7mEq/L)
108
What are some atrial changes associated with hyperkalemia?
* P wave flattens and widens (Intra-atrial block)
* PR prolongs then P wave disappears
109
What ventricular changes are associated with hyperkalemia?
* Followed by ventricular changes (K+ of 8-9mEq/L)
* QRS widens (intra-ventricular block)
110
What is the rhythm commonly seen with hyperkalemia?
SB → 1◦ AV Block → Junctional → Idioventricular → Asystole
111
What is the treatment of hyperkalemia?
* Reverse membrane effects with calcium
* Transfer extracellular potassium into cells
* Remove K+ from body
112
What are some medications that transfer extracellular potassium into cells?
D10W, Sodium bicarbonate, beta-2 agonists
113
What are some medications that can help remove K+ from body?
Proximal or loop diuretics, binding resins, HD
114
What are some ECG characteristics of hypocalemia?
* Long QT interval
* ST segment elongation
* Lowering and inversion of T wave (1/3 of cases
115
What are the ECG characteristics of hypercalcemia?
* Short QT interval
* ST segment narrowing
* Enhances early ventricular repolarization
