Patients w/ Conduction Probs Flashcards
(122 cards)
1
Q
How many seconds are the tiny boxes worth on a 6 second strip?
A
0.04 seconds
2
Q
How much are the bigger boxes worth on a six second strip?
A
0.20 seconds
3
Q
How many boxes are in a 6 seconds strip?
A
30
4
Q
1R 2R 3P 4PR 5QRS
A
1 Rate 2 Rhythm is regular or irregular? 3 P-wave 4 PR interval 5 QRS complex < .12 seconds?
5
Q
How do you find the rate for step 1 on a 6 second strip?
A
Count how many QRS complexes appear on a 6 second strip and multiply by 10
6
Q
What do you determine in step 2 about the rhythm?
A
If it is regular or irregular-look at QRS complexes
7
Q
What do you determine about the P-wave in step 3?
A
do they all look alike and do they come before and after the QRS complexes
8
Q
What is a normal PR Interval?
A
0.12-0.20 seconds
9
Q
How do you measure the PR intervals?
A
Measure from the beginning of the P-wave to the beginning of the QRS complex
-count how many tiny boxes are between and multiply by 0.04 seconds
10
Q
How do you measure the QRS duration in step 5?
A
measure from beginning of QRS complex to the end and multiply be 0.04 seconds
11
Q
What does the P-wave represent?
A
the electrical impulse starting in the SA node and spreading throughout the atria
-atrial depolarization
12
Q
What does the PR interval represent?
A
the time needed for SA node stimulation, atrial node depolarization, and conduction through AV node before ventricular depolarization
13
Q
What does the QRS complex represent?
A
ventricular depolarization
14
Q
How long is a normal QRS duration?
A
less than .12 seconds
15
Q
What does the T-wave represent?
A
ventricular repolarization or electrical recovery
16
Q
When does NORMAL Sinus Rhythm occur?
A
when the electrical impulse starts at the SA node and travels through the normal conduction pathway
17
Q
Normal Sinus Rhythm serves as a what?
A
Baseline
18
Q
Normal Sinus Rhythm Characteristics
A
Rate: 60-100 Rhythm: regular P-wave: normal and consistent PR Interval: b/t .12-.20 QRS duration: less than .12 seconds
19
Q
What is the ONLY difference b/t Normal Sinus Rhythm and Sinus Arrhythmia?
A
Irregular Rhythm
20
Q
A Sinus Arrhythmia’s irregular rhythm may correlate w/ what?
A
Breathing
Rate increases w/ inspiration and decreases w/ expiration
21
Q
When does Sinus Bradycardia occur?
A
when the SA node creates an impulse at a slower rate than normal
22
Q
What is the ONLY difference b/w Sinus Brady and Normal Sinus Rhythm?
A
rate is less than 60 bpm
23
Q
What are some causes of Sinus Brady?
A
- sleep
- pain
- athleticism
- vomiting/hypovolemia
- suctioning
- medications
- increased intracranial pressure
- MI
- anemia
24
Q
What medications may cause Sinus Brady?
A
- calcium channel blockers
- amiodarone
- beta blockers
- digoxin
25
Sinus Brady ECG Characteristics
```
Rate: < 60 bpm
Rhythm: regular
P-wave: present before and after QRS and looks same
PR: normal
QRS: normal
```
26
Treatment for symptomatic Sinus Brady may be what?
- transcutaneous pacing
- atropine
- dopamine
- epinephrine
27
When does Sinus Tachycardia occur?
When SA node creates an impulse at a faster rate than normal
28
What are some causes of Sinus Tachy?
- stress
- medications
- stimulants
- drugs
- emotions/agitation
- blood loss/hemorrhage/hypovolemia
- sepsis
- hyperthyroidism
- anemia
- infection/inflammation
29
ECG Characteristics of Sinus Tachycardia
```
Rate: > 100 bpm
Rhythm: regular
P-wave: before and after QRS and same
PR: normal
QRS: normal
```
30
What is a Premature Atrial Complex (PAC)?
single ECG complex that occurs when electrical impulse starts in the atrium before the next normal impulse from the SA node
31
What may cause a PAC?
- caffeine
- alcohol
- nicotine
- hypervolemia
- anxiety
- hypokalemia
- injury/infarction
32
ECG Characteristics w/ PAC
```
Rate: depends on underlying rhythm
Rhythm: irregular
P-wave: all same except one
PR interval: all normal except one
QRS duration: normal
```
33
How many PAC's occurring in one strip is considered to be a sign of worsening arrhythmia?
more than 6 per min
34
Where does Atrial Flutter occur?
in the Atrium
35
What is the ATRIAL rate for atrial flutter?
220-350 bpm
36
What happens w/ Atrial Flutter?
The atrial rate is faster than what the AV node can conduct so not all atrial impulses are conducted to the ventricle
37
Causes of Atrial Flutter
- CAD
- hypertension
- mitral/tricuspid valve disease
- hyperthyroidism
- chronic lung disease
- pulmonary emboli
- cardiomyopathy
38
S/S of Atrial Flutter IF present
- fatigue
- light headed
- chest pain
- SOB
- low BP
- blood clots
39
ECG Characteristics for Atrial FLUTTER
Rate: Atrial 220-350 bpm; Ventricular 75-150 bpm
Rhythm: usually regular
P-wave: flutter waves-"saw tooth pattern"
PR: not measurable
QRS: normal
40
What is the initial treatment for Atrial Flutter?
Cardioversion or radiofrequency ablation
41
Atrial Fibrillation causes what?
Rapid, disorganized , and uncoordinated electrical activity w/in the atria
42
A-fib can appear as what?
- transient, starting and stopping suddenly
- occur for short period of time
- may be persistent
43
Long-standing Persistent A-fib
continuous AF or lasting longer than 12 months
44
When is the term "Permanent A-fib" used?
when the physician and patient together decide to stop further attempts of NSR
45
Nonvalvular A-fib
AF exists in the absence of preexisting heart valve problems
46
Patients in A-fib are at an increased risk for what?
- blood clots/DVT
- Pulmonary embolism
- MI
- stroke
- kidney infarction
- myocardial ischemia
- heart failure
47
S/S of A-fib
- asymptomatic
- decreased CO
- fatigue
- malaise
48
ECG Characteristics of A-fib
```
Rate: Atrial Rate 300-400, w/ variable ventricle response
Rhythm: irregular
P wave: no discernible p-wave
PR: not measurable
QRS: normal
```
49
Treatment for A-fib depends on what?
- cause
- duration
- symptoms
- age
- comorbidities
50
Treatment for A-fib
-cardioversion by meds or electrical shock
51
Cardioversion via Medications
Intravenous ibutilide
procainamide
amiodarone
52
When will pharmacological cardioversions be more effective?
When A-fib is more recent
53
When are electrical cardioversions indicated?
when a patient w/ new onset AF is hemodynamically unstable
54
What will be performed before a cardioversion for a patient w/ new-onset AF for over 48 hours or when the onset is unknown?
trans-esophageal echocardiography (TEE)
55
Why is a TEE performed before a cardioversion?
to rule out left atrial thrombus because when a patient converts back to NSR the risk for PE is increased
56
How long does a patient need to be on anticoagulants after a cardioversion?
4 weeks to prevent thromboembolism
57
For patients who are unresponsive to medications w/ A-fib what is considered?
Pacemaker implantation or catheter ablation
58
Supra-ventricular Tachycardia is a broad term for what?
to describe tachycardias where the atrial or ventricular rate exceeds 100 bpm at rest
59
SVT electrical impulses are usually stimulated from where?
HIS bundle or AV node
60
SVT is the term that covers what?
- Sinus tachy
- Focal/multifocal atrial tachy
- junctional tachy
61
Symptoms of SVT vary depending on what?
- frequency/duration of episodes
- timing of SVT
- rhythm
62
S/S of SVT
- palpitations
- chest pain
- SOB
- dizziness
- syncope
- panic/anxiety
63
ECG Characteristics for SVT
```
Rate: > 100 bpm
Rhythm: regular
P wave: if visible sometimes inverted seen after QRS
PR: not measurable
QRS: in paroxysmal SVT its normal
```
64
Treatment for Atrial SVT depends on what?
- cause
- duration
- symptoms
- age
- comorbidities
65
What is recommended as the first step for Atrial SVT's to discontinue rhythm in patients who are hemodynamically stable?
Vagal maneuvers
66
What medication is given short term for patients w/ Stable SVT's?
Adenosine
67
If SVT becomes unstable what is the recommended treatment?
synchronized cardioversion
68
For ongoing management of SVT's patients mat be placed on what?
- beta blockers
- diltiazem
- verapamil
69
When does a Junctional Rhythm occur?
when the AV node instead of the SA node becomes the pacemaker of the heart
70
Why would the AV node take over?
- SA node slows from increased vagal tone
| - impulse cannot be conducted through AV node b/c of heart block
71
Junctional Escape Rhythm may be caused by what?
- acute coronary syndromes
- valvular disease
- hypoxia
- increased parasympathetic tone
- medications
72
What medications may cause junctional escape rhythms?
- digoxin
- beta blockers
- calcium channel blocker
73
ECG Characteristics for Junctional Escape Rhythms
Rate: 40-60 bpm
Rhythm: regular
P wave: if visible may be before, during, or after
QRS: normal
74
What is the treatment for Junctional escape rhythms if symptomatic?
Same as for bradycardia
- temporary/permanent pace maker
- IV atropine
- IV epinephrine
75
If there is a delay or defect in the conduction system w/in the ventricles what happens to the QRS complex?
It will be prolonged or widened
| > .12 seconds
76
What may cause Ventricular Arrhythmias?
- ventricular hypertrophy
- cardiomyopathy
- myocardial ischemia/infarction
77
When would Ventricular Arrhythmias require temporary pacing?
When there is an acute MI that progresses to complete heart block
78
What is a premature ventricular complex (PVC)?
Impulse that starts in the ventricle and is conducted through the ventricles before the next normal sinus impulse
79
PVC's may occur in normal healthy people because of what?
Intake of caffeine, nicotine, or alcohol
80
Causes of PVC's
- cardiac ischemia/infarction
- exercise
- fever
- hypervolemia
- heart failure
- tachycardia
- hypoxia
- acidosis
- hypokalemia
81
PVC's may be an early marker for what?
Heart failure
82
Patients w/ PVC's may be asymptomatic or complain of what?
their heart "skips a beat"
83
Bigeminy PVC
a rhythm in which every other complex is a PVC
84
Three or more successive PVC's are termed as what?
Ventricular Tachycardia
85
ECG Characteristics for PVC
```
Rate: depends on underlying rhythm
Rhythm: regular
P wave: depends on timing of PVC
PR: if in front of QRS its <0.12 sec
QRS: wider/abnormal in PVC
```
86
What is Ventricular Tachycardia defined as?
three or more consecutive ventricular beats occurring at a rate more than 100 bpm
87
Ventricular Tachycardia may occur with what?
- ACS
- after MI
- inherited arrhythmia syndromes
- electrolyte imbalances
- cardiomyopathies
- structural heart disease
88
Ventricular tachycardia can deteriorate into what?
Ventricular fibrillation
89
S/S Ventricular Tachycardia
- hypotension
- syncope
- pulselessness
- unresponsiveness
90
ECG Characteristics for Ventricular Tachy
```
Rate: 100-250 bpm
Rhythm: regular
P wave: not visible
PR interval: none
QRS: > 0.12 sec
```
91
Monomorphic Ventricular Tachy
consistent QRS shape and rate
92
Polymorphic V-tach
varying QRS shapes and rhythms
93
If a patient is stable w/ V-tach the only treatment may be what?
Continued assessment w/ 12-lead ECG
94
What is often the medication of choice for a stable patient w/ V-tach?
Amiodarone
95
What is the treatment of choice for Monophasic V-tach in symptomatic patient?
Cardioversion
96
When would the nurse begin to prepare the patient w/ V-tach for a cardioversion?
When the patient begins to demonstrate hypotension, shock, angina, symptoms of CHF, edema, or symptoms of cerebral hypoperfusion
97
What is Ventricular Fibrillation?
Rapid, disorganized ventricular rhythm that causes ineffective quivering of the ventricles
98
S/S of V-fib
Absence of audible heart beat, palpable pulse, and respirations
99
What is imminent w/ V-fib?
Cardiac arrest and death
100
ECG Characteristics for V-fib
```
Rate: often cannot be determined but > 220 bpm
Rhythm: irregular
P wave: not visible
PR: none
QRS: none
```
101
What is the treatment of choice for V-fib?
- immediate defibrillation
- immediate CPR
- activation of emergency services
102
What vasoactive medications should be delivered after the second rhythm check for someone in V-fib?
Epinephrine
103
What does a Ventricular Escape Rhythm occur? (Idioventricular Rhythm)
When the impulse starts in the conduction system below the AV node
104
Who is creating the impulse in a Ventricular Escape Rhythm?
Purkinje Fibers
105
ECG Characteristics of Ventricular Escape Rhythm
```
Rate: 20-40 bpm
Rhythm: regular
P wave: not visible
PR: none
QRS: 0.12 secs or more
```
106
If the rate is greater than 40 bpm w/ Ventricular Escape Rhythms it is known as what?
Accelerated ventricular escape rhythm
107
Treatment for Ventricular Escape Rhythm
- same as asystole if patient is in cardiac arrest
- if not in cardiac arrest same as if bradycardia
- administer IV atropine and vasopressors
- emergency pacing
108
What is Ventricular Asystole characterized as?
"flat line"
| Absent of QRS complexes confirmed in two different leads
109
How is Asystole treated?
Focusing on CPR and identifying underlying cause
110
Possible causes of Asystole
- hypoxia
- acidosis
- severe electrolyte imbalance
- overdose
- hypovolemia
- cardiac tamponade
- tension pneumothorax
- trauma
- hypothermia
111
When does SR w/ First Degree Heart Block occur?
When atrial conduction is DELAYED through the AV node, resulting in prolonged PR interval
112
Causes of First Degree Heart Block
- beta blockers
- calcium channel blockers
- digoxin
- vomiting
- Valsalva maneuver
113
ECG Characteristics of First Degree Heart Block
```
Rate: depends on underlying rhythm
Rhythm: regular
P wave: present before and after and consistent
PR: greater than 0.20 secs
QRS: normal
```
114
When is a patient w/ First Degree Heart Block treated?
When symptoms related to bradycardia are presentre
115
Second Degree Heart Block Type 1 is also known as what?
Wenckebach
116
What causes Second Degree Heart Block type 1?
a gradual and progressive conduction delay through the AV node
117
When does SDHB Type 1 occur?
When there is a repeating pattern in which all but 1 of a series of atrial impulses are conducted through the AV node
118
What is seen w/ the PR interval on an ECG of SDHB Type 1?
Increasing PR interval is seen w/ each successive beat until a P wave is seen w/o a resulting QRS
119
S/S of Wenckebach
- symptoms of bradycardia
- chest discomfort
- dyspnea
- hypotension
120
Causes of Wenckebach
- increased parasympathetic tone
- ischemia
- or meds that slow conduction
121
ECG Characteristics of Wenckebach
```
Rate: atrial faster than ventricular
Rhythm: Atrial regular/ventricular irregular
P wave: normal
PR: increasingly longer
QRS: normal
```
122
If patient w/ Wenckebach is symptomatic how is it treated?
Atropine or transcutaneous pacing
