Transcript Chapter 3 - CPRinthecity.com

EKG
Plain and Simple
Third Edition
CHAPTER
3
Lead Morphology and
Placement
EKG Plain and Simple, Third Edition
Karen M. Ellis
Copyright ©2012 by Pearson Education, Inc.
All rights reserved.
Media Directory
Slide 20
Slide 24
Slide 25
Slide 28
12-Lead Electrode Placement Animation
Electrode Placement for Cardiac Monitoring Video
Electrode Placement for EKG Video
Rule of Electrical Flow Animation
EKG Plain and Simple, Third Edition
Karen M. Ellis
Copyright ©2012 by Pearson Education, Inc.
All rights reserved.
Electrocardiography
• The recording of the heart’s electrical
impulses by way of electrodes on the skin
• Willem Einthoven: “Father of
electrocardiography” and the inventor of
the EKG machine
EKG Plain and Simple, Third Edition
Karen M. Ellis
Copyright ©2012 by Pearson Education, Inc.
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Bipolar Leads
• Three leads, all with positive and negative
poles
– Lead I: Right arm to left arm. Left arm is
positive electrode
– Lead II: Right arm to left leg. Left leg is
positive electrode
– Lead III: Left arm to left leg. Left leg is positive
electrode
EKG Plain and Simple, Third Edition
Karen M. Ellis
Copyright ©2012 by Pearson Education, Inc.
All rights reserved.
Figure 3-1 The Bipolar Leads
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Triaxial Diagram
• Formed by joining the lines representing
Leads I, II, and III at the middle
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Figure 3-2 The Triaxial Diagram
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Einthoven’s Triangle
• Formed by joining the lines representing
leads I, II, and III at their ends
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Figure 3-3 Einthoven’s Triangle
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Einthoven’s Law
• Lead I + Lead III = Lead II
• Lead II should have the tallest QRS
complex of the bipolar leads
• Can help determine if leads were
inadvertently placed on wrong limb
EKG Plain and Simple, Third Edition
Karen M. Ellis
Copyright ©2012 by Pearson Education, Inc.
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Figure 3-4 Einthoven’s Law
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Augmented Leads
• Three leads, all with only a positive pole
(unipolar leads)
– AVR: On right arm
– AVL: On left arm
– AVF: On left foot
• EKG machine augments the waveforms’
size
EKG Plain and Simple, Third Edition
Karen M. Ellis
Copyright ©2012 by Pearson Education, Inc.
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Figure 3-5 The Augmented Leads
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Figure 3-6 Triaxial Diagram with Augmented Leads
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Hexiaxial Diagram
• Formed by joining the lines representing
leads I, II, III, AVR, AVL, and AVF at the
middle
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Figure 3-7 Hexiaxial Diagram
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Bipolar and Augmented Leads
are also Called
• Frontal leads, as they are all located on
the front of the body
• Standard leads
• Limb leads
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Precordial (Chest) Leads
• Six unipolar leads that see the heart from
the horizontal plane. All are positive
electrodes
•
•
•
•
•
•
V1
V2
V3
V4
V5
V6
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Figure 3-8 The Precordial Leads
EKG Plain and Simple, Third Edition
Karen M. Ellis
Copyright ©2012 by Pearson Education, Inc.
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12-Lead Electrode Placement
Animation
Click on the screenshot to view an animation showing 12-Lead Electrode Placement.
Click again to pause the animation.
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Continuous Monitoring
• Allows monitoring of rhythm for a
prolonged time
• Requires altered electrode placement to
minimize artifact
• Bedside monitoring: Patient attached to an
EKG machine by a cable
• Telemetry: Remote cardiac monitoring of
ambulatory patients
EKG Plain and Simple, Third Edition
Karen M. Ellis
Copyright ©2012 by Pearson Education, Inc.
All rights reserved.
Figure 3-9 Bedside Monitor
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Figure 3-10 Lead Placement for Continuous Monitoring
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Electrode Placement for
Cardiac Monitoring Video
Click on the screenshot to view a video showing electrode placement for cardiac
monitoring.
Click again to pause the video.
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Electrode Placement for
EKG Video
Click on the screenshot to view a video showing electrode placement for EKG.
Click again to pause the video.
EKG Plain and Simple, Third Edition
Karen M. Ellis
Back to Directory
Copyright ©2012 by Pearson Education, Inc.
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Electrocardiographic Truths
• Positive QRS written by impulse travelling
toward positive electrode
• Negative QRS from impulse travelling
away from positive electrode
• Isoelectric QRS from impulse travelling
perpendicular to positive electrode
• Flat line written when there is no impulse
at all
EKG Plain and Simple, Third Edition
Karen M. Ellis
Copyright ©2012 by Pearson Education, Inc.
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Figure 3-11 Electrocardiographic Truths
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Rule of Electrical Flow Animation
Click on the screenshot to view an animation showing the Rule of Electrical Flow.
Click again to pause the animation.
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Normal Vector
• Vector: Arrow depicting the direction of
current flow
• Normal vector of heart’s current is top to
bottom, right to left
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Figure 3-12 Normal Vector
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Normal QRS Deflections
• Lead I: QRS should be positive
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Figure 3-13 Normal QRS Deflection in Lead I
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Normal QRS Deflections
• Lead II: QRS should be positive
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Figure 3-14 Normal QRS Deflection in Lead II
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Normal QRS Deflections
• Lead III: QRS should be positive
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Figure 3-15 Normal QRS Deflection in Lead III
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Normal QRS Deflections
• AVR: QRS should be negative
• AVR is the only frontal lead with a
negative QRS
EKG Plain and Simple, Third Edition
Karen M. Ellis
Copyright ©2012 by Pearson Education, Inc.
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Figure 3-16 Normal QRS Deflection in aVR
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Normal QRS Deflections
• AVL: QRS should be positive
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Figure 3-17 Normal QRS Deflection in aVL
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Normal QRS Deflections
• AVF: QRS should be positive
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Figure 3-18 Normal QRS Deflection in aVF
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Normal QRS Deflections
• V1: QRS should be negative
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Figure 3-19 Normal QRS Deflection in V1
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Normal QRS Deflections
• V6: QRS should be positive
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Figure 3-20 Normal QRS Deflection in V6
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Normal QRS Deflections
• The precordial leads will show a transition
from negative (V1 to V2) to isoelectric (V3
to V4) to positive (V5 to V6)
EKG Plain and Simple, Third Edition
Karen M. Ellis
Copyright ©2012 by Pearson Education, Inc.
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Normal QRS Deflections
EKG Plain and Simple, Third Edition
Karen M. Ellis
Copyright ©2012 by Pearson Education, Inc.
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Normal QRS Deflections
EKG Plain and Simple, Third Edition
Karen M. Ellis
Copyright ©2012 by Pearson Education, Inc.
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Classroom Response System
EKG Plain and Simple, Third Edition
Karen M. Ellis
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Pop Question 1
On your EKG, Lead I is 5 mms tall, Lead II is
12 mms tall, and Lead III is 9 mms tall.
Based on Einthoven’s Law, you conclude
that
A. The leads were properly placed
B. The leads may have been inadvertently
placed on the wrong limbs
EKG Plain and Simple, Third Edition
Karen M. Ellis
Copyright ©2012 by Pearson Education, Inc.
All rights reserved.
Pop Question 1 (continued)
On your EKG, Lead I is 5 mms tall, Lead II is
12 mms tall, and Lead III is 9 mms tall.
Based on Einthoven’s Law, you conclude
that
C. Einthoven’s Law has nothing to do with
lead placement
D. Lead II should have a smaller QRS
complex
EKG Plain and Simple, Third Edition
Karen M. Ellis
Copyright ©2012 by Pearson Education, Inc.
All rights reserved.
Pop Question 1 Answer
On your EKG, Lead I is 5 mms tall, Lead II is
12 mms tall, and Lead III is 9 mms tall.
Based on Einthoven’s Law, you conclude
that
A. The leads were properly placed
B. The leads may have been inadvertently
placed on the wrong limbs
EKG Plain and Simple, Third Edition
Karen M. Ellis
Copyright ©2012 by Pearson Education, Inc.
All rights reserved.
Pop Question 1 Answer
(continued)
On your EKG, Lead I is 5 mms tall, Lead II is
12 mms tall, and Lead III is 9 mms tall.
Based on Einthoven’s Law, you conclude
that
C. Einthoven’s Law has nothing to do with
lead placement
D. Lead II should have a smaller QRS
complex
EKG Plain and Simple, Third Edition
Karen M. Ellis
Copyright ©2012 by Pearson Education, Inc.
All rights reserved.
Pop Question 2
Leads I and AVR share which limb in
common?
A. Right arm
B. Right leg
C. Left arm
D. Left leg
EKG Plain and Simple, Third Edition
Karen M. Ellis
Copyright ©2012 by Pearson Education, Inc.
All rights reserved.
Pop Question 2 Answer
Leads I and AVR share which limb in
common?
A. Right arm
B. Right leg
C. Left arm
D. Left leg
EKG Plain and Simple, Third Edition
Karen M. Ellis
Copyright ©2012 by Pearson Education, Inc.
All rights reserved.
Pop Question 3
Which of the following leads have a positive
pole on the left arm?
A. II, III, AVF, and V5
B. I and AVL
C. I, AVR, and V1
D. V1 and V2
EKG Plain and Simple, Third Edition
Karen M. Ellis
Copyright ©2012 by Pearson Education, Inc.
All rights reserved.
Pop Question 3 Answer
Which of the following leads have a positive
pole on the left arm?
A. II, III, AVF, and V5
B. I and AVL
C. I, AVR, and V1
D. V1 and V2
EKG Plain and Simple, Third Edition
Karen M. Ellis
Copyright ©2012 by Pearson Education, Inc.
All rights reserved.
Pop Question 4
Your patient has a positive QRS in AVR.
This means the current of her heart is
travelling
A. Toward the right arm
B. Away from the right arm
C. Toward the left arm
D. Away from the left arm
EKG Plain and Simple, Third Edition
Karen M. Ellis
Copyright ©2012 by Pearson Education, Inc.
All rights reserved.
Pop Question 4 Answer
Your patient has a positive QRS in AVR.
This means the current of her heart is
travelling
A. Toward the right arm
B. Away from the right arm
C. Toward the left arm
D. Away from the left arm
EKG Plain and Simple, Third Edition
Karen M. Ellis
Copyright ©2012 by Pearson Education, Inc.
All rights reserved.
Pop Question 5
The QRS complex should be negative in
which leads?
A. II, III, AVF
B. I, AVL, V5-6
C. AVR, V5, V6
D. AVR, V1, V2
EKG Plain and Simple, Third Edition
Karen M. Ellis
Copyright ©2012 by Pearson Education, Inc.
All rights reserved.
Pop Question 5 Answer
The QRS complex should be negative in
which leads?
A. II, III, AVF
B. I, AVL, V5-6
C. AVR, V5, V6
D. AVR, V1, V2
EKG Plain and Simple, Third Edition
Karen M. Ellis
Copyright ©2012 by Pearson Education, Inc.
All rights reserved.