Defibrillators, Pacemakers, etc. Flashcards Preview

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Flashcards in Defibrillators, Pacemakers, etc. Deck (183)
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1
Q

What does CRMD stand for?

A

Cardiac rhythm management devices

2
Q

A dual chamber pacemaker paces the:

A

Right atrium and right ventricle

3
Q

In a dual chamber pacemaker, the pacing leads of the pacemaker are placed in the:

A

right atrium and right ventricle

4
Q

The basic structure of a pacemaker consists of:

A

a pacemaker and pacing leads

5
Q

What are the dimensions of a modern day pacemaker?

A

2 g, 1 cc

6
Q

What is sinus node disease?

A

Symptomatic diseases of impulse formation

7
Q

Symptomatic diseases of impulse formation:

A

Sinus node disease

8
Q

Define sinus node disease:

A

Symptomatic diseases of impulse formation

9
Q

Name that classifies any symptomatic disease of impulse formation

A

Sinus node disease

10
Q

Sinus node disease implies a problem with:

A

impulse formation

11
Q

Impulse formation is negatively affected in what type of disease?

A

Sinus node disease

12
Q

Define diseases of atrioventricular node:

A

Symptomatic diseases of impulse conduction

13
Q

Impulse formation is affected by? Impulse conduction?

A

Impulse formation: sinus node diseases

Impulse conduction: diseases of the atrioventricular node

14
Q

Symptomatic diseases of impulse conduction

A

Diseases of the atrioventricular node

15
Q

The atrioventricular node is to impulse ___________ as the sinus node is to impulse ________.

A

AV node: impulse conduction

Sinus node: impulse formation

16
Q

Impulse conduction is impaired by what types of diseases?

A

Diseases of the atrioventricular node

17
Q

Diseases of the atrioventricular node are defined by:

A

Symptomatic diseases of impulse conduction

18
Q

For what two reasons do most patients have pacemakers?

A

Sinus node disease and atrioventricular disease

19
Q

HRS stands for:

A

Heart rhythm society

20
Q

BPEG stands for:

A

British Pacing and Electrophysiology Group

21
Q

NBG stands for:

A

NASPE and BPEG Generic

22
Q

What are HRS, BPEG, and NBG?

A

Pacemaker classification systems

23
Q

Three types of pacemaker classification systems?

A

BPEG, NBG, NASPE

24
Q

Classification of bradycardia support pacemakers: Positions 12345

A

1) What does it pace?
2) What does it sense?
3) How does it respond?
4) Programmable
5) Multisite pacing

25
Q

Classification of bradycardia support pacemakers: 1

A
1) What does it pace? 
V: Ventricle
A: Atria
D: Dual
O: None
26
Q

Classification of bradycardia support pacemakers: 2

A
2) What does it sense? 
V: Ventricle 
A: Atrial 
D: Dual 
O: None
27
Q

Classification of bradycardia support pacemakers: 3

A
3) How does it respond? 
I: Inhibited 
T: Triggered
D: Dual 
O: None
28
Q

Classification of bradycardia support pacemakers: 4

A

4: Programmable
R: Rate modulated
O: None

29
Q

Classification of bradycardia support pacemakers: 5

A
5: Multisite pacing
V: Ventricle
A: Atrial 
D: Dual
O: None
30
Q

Of the classification of bradycardia support pacemakers, what three groups will you deal with in the OR?

A

1: What does it pace?
2: What does it sense?
3: How does it respond?

31
Q

123 of bradycardia support pacemakers?

A

1: What does it pace?
2: What does it sense?
3: How does it respond?

32
Q

What are the possible responses of a bradycardia support pacemaker?

A

Inhibited
Triggered
Dual (Inhibited + Triggered)
O (None)

33
Q

Position 1 in bradycardia support pacemakers:

A

Pacing chambers

34
Q

Position 2 in bradycardia support pacemakers:

A

Sensing chambers

35
Q

Position 3 in bradycardia support pacemakers:

A

Responses to sensing

36
Q

Position 4 in bradycardia support pacemakers:

A

Programmability

37
Q

Position 5 in bradycardia support pacemakers:

A

Multisite pacing

38
Q

Which position in bradycardia support pacemakers refers to multisite pacing?

A

Position 5

39
Q

Which position in bradycardia support pacemakers refers to programmability?

A

Position 4

40
Q

Which position in bradycardia support pacemakers refers to response to sensing?

A

Position 3

41
Q

Which position in bradycardia support pacemakers refers to chambers sensed?

A

Position 2

42
Q

Which position in bradycardia support pacemakers refers to chambers paced?

A

Position 1

43
Q

What is multisite pacing?

A

Pacing electrodes are placed at multiple sites within a particular chamber or on both chambers of the same pedigree

44
Q

Pacing electrodes are placed at multiple sites within a particular chamber or on both chambers of the same pedigree

A

Multi-site pacing

45
Q

T/F: Multi-site pacing is pacing electrodes placed at multiple sites in two different chambers

A

False; multi-site pacing is pacing electrodes placed at multiple sites within a particular chamber or on both chambers of the same pedigree

46
Q

“Rate modulation” refers to which position on a bradycardia support pacemaker?

A

Position 4: programmability

47
Q

“Inhibited” means:

A

withhold a pacemaker output in response to a sensed event

48
Q

What does “withhold a pacemaker output in response to a sensed event” mean?

A

Position 3: Response to sensing, inhibited

49
Q

What all is included the “dual” mode of response to sensing?

A

Inhibiting the pacemaker response
Tracking the sensed event
Inhibit the output on the sensed channel and triggering an output to maintain AV synchrony

50
Q

What is the “triggered” mode of response to sensing?

A

The pacing device emits a pulse only in response to a sensed event

51
Q

What mode of response to sensing is used when the device is being tested?

A

Triggered

52
Q

Explain an example DDD.

A

Sensed atrial signal will cause the device to inhibit atrial output. A timer starts that will cause a triggered ventricular output after a certain interval, but if a patient has an R wave during the triggered interval the ventricular output will be inhibited

53
Q

What are the three asynchronous modes of a pacemaker during application of a magnet?

A

AOO: fixed rate atrial pacing
VOO: fixed rate ventricular pacing
DOO: fixed rate AV sequential pacing

54
Q

AOO:

A

fixed rate atrial pacing

55
Q

VOO:

A

fixed rate ventricular pacing

56
Q

DOO:

A

fixed rate AV sequential pacing

57
Q

Fixed rate AV sequential pacing:

A

DOO

58
Q

When are most pacemakers asynchronous?

A

During application of a magnet

59
Q

When a magnet is placed over a pacemaker, what possible modes occur?

A

DOO: fixed rate AV sequential pacing
AOO: fixed rate atrial pacing
VOO: fixed rate ventricular pacing

60
Q

Main characteristics of DDD?

A

Paces atrium and ventricles

Senses atrium and ventricular signals

61
Q

In DDD, a sensed atrial signal will cause:

A

the device to inhibit atrial output

62
Q

In DDD, what causes the device to inhibit atrial output?

A

Sensed atrial signal

63
Q

In DDD, what occurs after a sensed atrial signal causes the pacemaker to inhibit atrial output?

A

A timer starts that will cause a triggered ventricular output after a certain interval

64
Q

In DDD, what occurs if a patient has an R wave during the triggering interval?

A

The ventricular output is inhibited

65
Q

In DDD, what aspects do pacemakers inhibit?

A

Once atrial activity is sensed, an atrial output is inhibited for the sake of pacemaker control. Ventricular output is also inhibited if a patient has an R-wave during a set triggering interval.

66
Q

In DDD, what aspects do pacemakers trigger?

A

A pacemaker starts a timer for a set interval after which a ventricular output is triggered.

67
Q

Which mode paces atrium and ventricles + senses atrium and ventricular signals?

A

DDD

68
Q

What pacing mode are most pacemakers?

A

Most pacemakers are dual chamber (AV).

69
Q

AOO:

A

Atrial asynchronous pacing

70
Q

VOO:

A

Ventricular asynchronous pacing

71
Q

DOO:

A

Dual-chamber (AV) asynchronous pacing

72
Q

AAI:

A

Atrial-inhibited pacing

73
Q

VVI:

A

Ventricle-inhibited pacing

74
Q

VAT:

A

Atrial triggered, ventricular pacing

75
Q

VDD:

A

Atrial triggered, ventricular-inhibited pacing

76
Q

DVI:

A

Dual-sequential, ventricular-inhibited pacing

77
Q

DDI:

A

Dual chamber, dual-sequential pacing

78
Q

DDD:

A

Dual-sequential, atrial trigger, ventricular inhibited pacing or AV universal pacing

79
Q

How many possible pacing modes for bradycardia are there?

A

10

80
Q

In what form does a pacemaker jolt appear on an EKG? Why?

A

As a PVC because the electrical impulse always originates from somewhere other than the SA node (so an unnatural path)

81
Q

What is a biventricular pacemaker?

A

BiV or Cardiac resynchronization therapy (CRT): The pacemaker paces the right and left ventricle as well as the right atrium.

82
Q

How many leads does a biventricular pacemaker have? Where are they placed?

A

Three:
One is placed in the right atrium.
One is placed in the right ventricle.
The left ventricular lead is actually placed in the coronary sinus.

83
Q

T/F: the left ventricular lead of a biventricular pacemaker is placed at the base of the left ventricle of the heart.

A

False; it is actually placed in the coronary sinus.

84
Q

What is the main function and benefit to a biventricular pacemaker?

A

A biventricular pacemaker sends small electrical impulses to the lower chambers of the heart to help them beat in a more synchronized pattern

85
Q

Two parts of biventricular (CRT) system?

A

1) Heart device + battery

2) Leads

86
Q

Two types of biventricular (CRT) devices?

A
CRT pacemaker (CRT-P)
CRT defibrillator (CRT_D)
87
Q

Another name for endocardial leads?

A

Transvenous leads

88
Q

Two ways to secure endocardial (transvenous) leads?

A

Active fixation: metal screw-in

Passive fixation: rubber fins or tines

89
Q

If you secure an endocardial lead using metal screw-in, what type of fixation is that?

A

Active fixation

90
Q

If you secure an endocardial lead using rubber fins or tines, what type of fixation is that?

A

Passive fixation

91
Q

Which type of lead polarity is most reliable?

A

Unipolar

92
Q

Which type of lead polarity has improved rejection for better sensing?

A

Bipolar

93
Q

Which portion of the pacemaker leads are unipolar?

A

Case + lead tip

94
Q

Which portion of the pacemaker leads are bipolar?

A

Lead tip

95
Q

Benefit to unipolar leads?

A

Highest reliability

96
Q

Benefit to bipolar leads?

A

Improved rejection for better sensing

97
Q

Which lead EKG tracing has larger pacing artifacts on it, bipolar or unipolar? Why?

A

Unipolar; there is a larger pacing circuit on unipolar leads, so there is larger pacing artifact.

98
Q

Which type of lead is the spare in epicardial pacemakers?

A

The bipolar lead is the spare in case the working lead (unipolar) no longer functions.

99
Q

How do leadless pacemakers function in the heart?

A

Leadless is a bit of a misnomer because the right ventricle is still stimulated by a lead. Once the pulse generator picks up on the electrical activity of the pacemaker, it sends an ultrasonic wave into a leadless electrode implanted in the LV.

100
Q

Where are leadless electrodes typically implanted?

A

LV

101
Q

In a bipolar temporary pacing electrode, which portion of the lead is positive and which is negative?

A

The tip electrode is negative and the ring electrode is positive.

102
Q

Why is it customary to consider the tip electrode negative in a bipolar temporary pacing electrode?

A

Cathodal pacing has a lower threshold (minimum voltage required for capturing the chamber paced).

103
Q

What patients would receive a pacemaker with VDD settings? (Pacing in triggered and inhibited mode)

A

A patient with a functioning SA node but a non-functioning AV node

104
Q

What is the difference between the EKG tracings of VAT and VOO?

A

Both demonstrate spontaneous atrial activity and paced ventricular activity, but the equal PR intervals throughout every beat in VAT mode is the primary difference.

105
Q

What type of pacing adjusts heart rate to level of activity?

A

Rate responsive (modulation) pacing

106
Q

What are the two types of activity sensors in rate responsive (modulation) pacing?

A

Motion (vibration)

Ventilation (bioimpedance)

107
Q

Motion (vibration) correlates to which sensor status in rate responsive (modulation) pacing?

A

G sensor (accelerometer)

108
Q

Ventilation (bioimpedance) correlates to which sensor status in rate responsive (modulation) pacing?

A

MV sensor

109
Q

Which is higher at baseline in rate responsive (modulation) pacing, G sensor or MV sensor?

A

G sensor (accelerometer)

110
Q

What is the general recommendation for rate responsive pacemakers during surgery? Why?

A

Generally understood to turn them off to prevent confusion between inherent tachycardia and pace-maker induced tachycardia

111
Q

Why is pacemaker-induced tachycardia a common issue with rate responsive pacing during surgery?

A

The sensor that measures minute ventilation is extremely sensitive to stray electromagnetic interference; the pacemaker misunderstands the interference to be an increase in minute ventilation (increased activity) and increases the HR in response.

112
Q

Which sensor in rate responsive pacing provides a fast response at beginning of exercise and indicates end of exercise?

A

G sensor (accelerometer)

113
Q

Function of G sensor in rate responsive pacing?

A

Provides a fast response at beginning of exercise and indicates end of exercise

114
Q

Which sensor in rate responsive pacing provides a physiological and gradual response to exercise, detects increase in metabolic need and adapts pacing rate in proportion to exercise?

A

MV sensor (minute ventilation)

115
Q

Function of MV sensor in rate responsive pacing?

A

Provides a physiological and gradual response to exercise, detects increase in metabolic need and adapts pacing rate in proportion to exercise

116
Q

In rate responsive pacing, there is often bioimpedance between:
Which sensor senses bioimpedance?

A

Bioimpedance between atrial lead and body of pacemaker

Sensed by the MV sensor (minute ventilation, bioimpedance)

117
Q

Name some surgical situations in which pacemakers should be reprogrammed prior to surgery.

A
Any rate responsive device
Special pacing indication, HOCM, DCM, etc.
Pacemaker-dependent patients
Major procedures in chest + abdomen 
Rate enhacements
Lithotripsy
Transurethral resection
Hysteroscopy
ECT
Succinylcholine use 
MRI
118
Q

What does Biggs want you to remember about what kind of steps to take w/ patients w/ pacemakers preoperatively?

A
  1. Identify whether or not the patient has a pacemaker or a defibrillator.
  2. Have the pacemaker or defibrillator interrogated.
  3. Obtain a copy of this interrogation.
  4. Determine the patient’s underlying rate and rhythm.
  5. Identify the magnet rate and rhythm, if any.
  6. Turn minute ventilation rate responsiveness off.
  7. Program all rate enhancements off.
119
Q

What does Biggs want you to remember about what kind of steps to take w/ patients w/ pacemakers intraoperatively?

A
  1. Monitor cardiac rhythm with pulse ox or A-line.
  2. Ask the surgeon to not use monopolar ESU.
  3. Use bipolar ESU if possible; if not, a pure cut is better than a “blend” or a “coag”.
  4. Place ESU return pad.
  5. If ESU causes oversensing, limit periods of asystole.
120
Q

What is the major first thing you MUST do after surgery w/ patient w/ pacemaker?

A

Have pacemaker interrogated.

121
Q

What is the general rule if the surgeon must use a monopolar ESU on a patient w/ pacemaker?

A

Clean cuts are better than “blends” or “coags”.

122
Q

The parts of the preanesthetic pulse generator evaluation that Biggs wants you to know:

A

1) Identify type of device
2) Determine patient’s underlying rhythm
3) Obtain history of generator events
4) Interrogate the device
5) Ensure magnet detection is enabled.

123
Q

What is “blend” on an ESU?

A

A broad radiofrequency

124
Q

HRS stands for:

A

Heart rhythm society

125
Q

Biotronik is asynchronous at what rate:

A

Asynchronous pacing at 90 bpm (DOO or VOO)

126
Q

Boston Scientific is asynchronous at what rate:

A

Asynchronous pacing at 100 bpm (DOO with maximum AV delay or VOO)

127
Q

ELA/Sorin is asynchronous at what rate:

A

Asynchronous pacing at 96 bpm (DOO with maximum AV delay or VOO)

128
Q

Medtronic is asynchronous at what rate:

A

Asynchronous pacing at 85 bpm (DOO or VOO)

129
Q

Which pacemaker type is asynchonous in DOO or VOO?

A

Medtronic + Biotronik + St. Jude Medical

130
Q

Which pacemaker type is asynchronous in DOO with maximum AV delay or VOO?

A

ELA/Sorin or Boston Scientific

131
Q

St. Jude Medical is asynchronus at what rate:

A

100 bpm

132
Q

Temporary internal pacing is done via what type of catheter?

A

Bipolar RV pacing catheter

133
Q

T/F: sometimes, instead of using a bipolar RV pacing catheter, temporary pacing will utilize a Swan-Ganz catheter.

A

True

134
Q

How many electrodes on an SG catheter can pace the heart?

A

5

135
Q

Where are atrial leads located on a SG catheter?

A

At 30 cm mark

136
Q

Why are there more atrial leads than ventricular?

A

It is more difficult to capture the atria than the ventricle.

137
Q

Temporary (internal) pacing: when an electrode is placed in the esophagus, what portion of the heart is it reading?

A

Left atrium

138
Q

Temporary (internal) pacing: when an electrode is placed in the stomach, what portion of the heart is it reading?

A

Ventricle

139
Q

When using a defibrillator, what are the three main steps?

A
  1. Select the size of the charge you wish to deliver.
  2. Charge the defibrillator.
  3. Deliver a shock if necessary.
140
Q

Besides producing an EKG, what are three other forms of monitoring that a defibrillator is capable of?

A

CO2
SPO2
NIBP

141
Q

On your standard defibrillator, which button should you press to take an NIBP reading?

A

The button on the lower right of the screen

142
Q

What is “M” on a paced EKG?

A

Timing mark: defines when a shock will be applied in the cardiac cycle

143
Q

Why must the timing mark avoid the T-wave?

A

A shock during this period may fibrillate the ventricles (torsades)

144
Q

If someone references the “vulnerable period” of an EKG, they are referring to:

A

T-wave (ventricular repolarization)

145
Q

What does AICD stand for?

A

Automatic implantable cardio-defibrillator

146
Q

What are the four functions of an AICD?

A

Antitachycardic pacing
Cardioversion
Defibrillation
Bradycardia pacing

147
Q

What does NASPE stand for?

A

North American Society for Pacing and Electrophysiology

148
Q

What does NBD stand for?

A

NASPE/BPEG defibrillator

149
Q

How many positions does the NBD have?

A

4

150
Q

What are the four positions of the NBD?

A

1) Where does it shock?
2) Antitachycardic chambers
3) Tachycardia detection
4) Antibradycardia pacing chambers

151
Q

Which positions on NBD have VADO as options?

A

1) Where does it shock?
2) Antitachycardic chambers
4) Antibradycardic pacing chambers

152
Q

Possible actions of third position of NBD (tachycardia detection)?

A

E: electrogram
H: hemodynamic

153
Q

Antitachycardic functions of defibrillators (ICD/CRT):

A
P = Pace heart out of tachycardic rhythm 
S = Shock the heart
D = Dual, paced and shocked
O = none
154
Q

Most common antitachycardia function of CRT (a bradycardia device)?

A

O = none

155
Q

Most common antitachycardia function of ICD?

A

D = Dual, paced and shocked

156
Q

Pacer-cardioverter-defibrillators are usually placed in the:

A

abdomen

157
Q

How do pacer-cardioverter-defibrillators work?

A

The pulse generator receives information from two sensing leads and delivers precisely programmed electrical impulses to the heart through two or three patch leads.

158
Q

Describe the latest transvenous fibrillation systems:

A

A single catheter in the right ventricular apex

159
Q

Why don’t these devices burn holes in the SVC when they deliver shocks?

A

They only deliver a shock for a small amount of time to prevent the tissue from burning.

160
Q

In a defibrillator, what type of electrode is the RV pacing electrode?

A

It is pacing/sensing/shock electrode; integrated bipolar

161
Q

Purpose of SVC electrode in defibrillator?

A

Shock, only shock

162
Q

Function of tip electrode of a defibrillator?

A

Sensing/Pacing

Tined lead

163
Q

Where does a true bipolar lead sense?

A

Between the distal tip and the proximal ring

164
Q

How many coils do true bipolar leads have?

A

A single coil

165
Q

Where do integrated coil leads pace and sense?

A

Between the tip and the distal coil

166
Q

By what means is the distal coil useful?

A

Used for sensing, pacing, and defibrillation

167
Q

What is the purpose of the second, more proximal coil in integrated leads?

A

Increases lead surface area for defibrillation

168
Q

Normal shock for a defibrillator is how many Joules?

A

10-30 J

169
Q

T/F: Medication is actually proven to be more effective as an using a defibrillator.

A

False; defibrillators reduce death 39% in the first year.

170
Q

If the patient is in V-tach, should you cardiovert or defibrillate them?

A

You can technically cardiovert V-tach as long as you time the shock immediately after ventricular depolarization.

171
Q

If the patient is in V-fib, should you cardiovert or defibrillate them?

A

Defibrillate them

172
Q

Which is more efficient at depolarizing the heart, a biphasic or monophasic defibrillator waveform?

A

Biphasic

173
Q

Maximum amount of energy you can use in a biphasic delivery for defibrillation?

A

200 J

174
Q

Maximum amount of energy you can use in a biphasic delivery for synchronized cardioversion?

A

200 J

175
Q

Maximum amount of energy you can use in a biphasic delivery for internal defibrillation?

A

50 J

176
Q

How much more energy can monophasic defibrillation safely deliver than biphasic?

A

None–they can both deliver a maximum of 50 J.

177
Q

Steps in energy delivery for defibrillation (biphasic)?

A

120, 150, 200, 200 J

178
Q

Steps in energy delivery for synchronized cardioversion (biphasic)?

A

70, 120, 150, 200 J

179
Q

Steps in energy delivery for pediatric defibrillation (biphasic)?

A

2 J/ kg

180
Q

Steps in energy delivery for internal defibrillation (biphasic)?

A

5, 10, 20, 30, 50 J

181
Q

Internal defibrillator panels are placed directly across the heart and deliver a shock of:

A

10-30 J

182
Q

How does placing a magnet affect ELA/Sorin pacing function?

A

Magnet rate changes but continues in DDD mode (from 96 to 80 bpm)

183
Q

Which common pacemakers have a tone with magnet placement?

A

Medtronic, Boston Scientific