Cardiac Monitoring Einthonvens Triangle

Overview

Click To Begin Cardiac Monitoring Einthonvens Triangle Training

Overview

Cardiac Monitoring
&
Einthonven's Triangle

Thomas E. O'Brien
AS CCT CRAT RMA CCMA

Using This Presentation

how to use this presentation image

Introduction

Part 1

Cardiac monitoring is commonly performed in many areas in critical care. Applying a cardiac monitor is a simple task, but the circumstances may be very different from pre-hospital to the emergency department to surgery, including pre and post operatively and the myriad of intensive care units and telemetry.

Part 2

The important thing to remember is that the patient has a monitor applied for a specific reason. Remain diligent in your observation and report any changes noted during "monitoring".

A cardiac monitor is a tool to be used to assist with assessment of the patient. Remember to always treat the patient and not the "monitor".

Part 3

An unresponsive patient with what appears to be Normal Sinus Rhythm may in fact be clinically dead. They may have something called "Pulseless Electrical Activity".

Pay strict attention to your patient's vital signs and level of consciousness during monitoring.


Introduction (Con't)

Part 4 (Cont)

Treat the patient, not the monitor.

Loose, or dried out sensors (electrodes) or broken cables may cause a tracing to appear much the same as one of these life-threatening dysrhythmias.

Part 5

What appears to be Ventricular Tachycardia might occur because the patient is brushing their teeth. This is referred to as "toothbrush tachycardia".

  • This is caused by the repetitive body movement when brushing your teeth.
  • This is not an actual cardiac event.
  • Remember if you have an unresponsive patient, call a "code blue" (follow your facility's protocol) and begin emergency procedures.

Part 6

A variety of manufacturers offer a wide variety of cardiac monitors. A majority will have three or five cables. We will focus on the most common type today, the three-cable device.


Sensor Placement

Triangle

The three sensors applied may be placed in a few different locations, but ultimately they form a "triangle" around the heart.

This often referred to as Einthoven's Triangle.

Locations

  • One sensor is placed on either the right wrist, right deltoid or upper outer aspect of the chest, just inside the right shoulder.
  • The next sensor is placed on either the left wrist, left deltoid or upper outer aspect of the chest, just inside the left shoulder.
  • Finally, this last sensor is placed at either the inner left lower leg (just above the ankle) or at the left lateral costal margin of the ribs.

Views

Introduction

Leads I, II, & III are referred to as "bipolar leads". This is due to having two sensors on the skin surface making the positive and negative pole for this particular view.

When monitoring patients in one of these views, the sensor not involved in the "lead circuit" will become the ground.

Which Leads?

Einthoven's Triangle is formed by which three leads?

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Answer

Einthoven's Triangle is formed by which three leads?

  • Right Shoulder (arm)
  • Left Shoulder (arm)
  • Left Leg
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Einthoven's Triangle

Introduction

By use of three sensors, one each placed on the right arm, left arm and left leg, we are able to obtain six different views.

The first three views I will review are called Standard Leads I, II and III These views are referred to as "bipolar leads" due to two sensors utilized on the skin surface (one is positive and the other is negative – just like a battery) to complete the circuit.

The other three views are aVR, aVL and aVF. These will be discussed shortly.

One last comment, direct views of the heart will always be from the position of the positive pole i.e. Lead II and aVF positive pole is the left leg. These would be "inferior" views.

Overview


Lead I

Lead I Ground

Where is the ground?

Left Leg


Lead II

Where is the ground?

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Answer

Left Arm (shoulder)

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Lead III

Where is the ground?

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Answer

Right Arm (shoulder)

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Augmented Limb Leads

Discussion

The heart is the "negative" pole or terminus for all augmented leads.

The sensor on the skin surface is the positive (+) pole.

Augmented leads are "unipolar" due to one sensor being on the skin surface.

The flow of electricity is measured from the heart to either the:

  • right arm (aVR)
  • left arm (aVL)
  • left leg or foot (aVF)

aVR Illustrations

aVR Question

aVR views the heart from which direction?

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aVR Answer

aVR views the heart from which direction? Right Arm

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aVL Illustrations

aVL Question

aVL views the heart from which direction?

“ecg

aVL Answer

aVL views the heart from which direction? Left Arm

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aVF Illustrations

aVF Question

aVF views the heart from which direction?

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aVF Answer

aVF views the heart from which direction? Left Foot (Leg)

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Test Questions #1-3

Question #1

Lead I is formed by which two locations?

A. Right arm and right leg
B. Left arm and left leg
C. Right arm and left leg
D. Left arm and right arm




Question #2

The ground for Lead III is located on the

A. Right leg
B. Left leg
C. Right arm
D. Left arm




Question #3

Lead II is formed by which two locations?

A. Right arm and right leg
B. Left arm and left leg
C. Right arm and left leg
D. Left arm and right arm





Test Questions #4-6

Question #4

The lead aVL the positive pole is located on the

A. Lumbar spine
B. Left leg
C. Left costal margin of the ribs
D. Left shoulder (arm)




Question #5

In lead aVF the sensor is placed on the

A. Front of the chest
B. Foramen magnum
C. Right leg (foot)
D. Left leg (foot)




Question #6

The nurse walks into patient room and notices the patient monitor displaying a flatline. Does the nurse:

A. Interpret it as Asystole and then go to lunch
B. Call a Code
C. Take a break
D. Try to talk to patient while immediately checking leads





Test Questions #7-9

Question #7

Lead III is formed by which two locations?

A. Right arm and right leg
B. Left arm and left leg
C. Right arm and left leg
D. Left arm and right arm




Question #8

The ground for Lead II is located on the

A. Right leg
B. Left leg
C. Right Arm
D. Left Arm




Question #9

Lead I is formed by which two locations?

A. Right arm and right leg
B. Left arm and left leg
C. Right arm and left leg
D. Left arm and right arm





Test Questions #10-12

Question #10

The lead aVR the positive pole is located on the

A. Right Atrium
B. Right leg
C. Right costal margin of the ribs
D. Right shoulder (arm)




Question #11

In cardiac monitoring it is best to always

A. React based upon the tracing on the cardiac monitor
B. Treat the monitor, not the patient
C. Always call a code blue when you see asystole
D. Always treat the patient, not the monitor




Question #12

You are monitoring a patient when suddenly the monitor goes flatline (asystole) while the patient continues talking to you. What is the first thing that you do?

A. Keep talking with the patient
B. Call a Code
C. Take a break
D. Check the patient and equipment





Test Questions #13-14

Question #13

Which lead is demonstrated by the following image?

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A. Lead I
B. Lead III
C. Lead aVL
D. Lead aVF




Question #14

Which lead is demonstrated by the following image?

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A. Lead I
B. Lead II
C. Lead aVL
D. Lead aVF





Test Questions #15-18

Question #15

Some leads are referred to as unipolar because

A. Only one sensor on the skin surface
B. A patient has only one arm
C. A patient only has one leg
D. The cardiac monitor has limited capability




Question #16

Some leads are referred to as bipolar because?

A. The cardiac monitor's increased capability
B. The monitor has both AC and DC power sources
C. The monitor can also run 12-Lead EKGs
D. There are two sensors on the skin surface completing the circuit for that view




Question #17

Which of the following activities may cause the cardiac monitor to display a tracing very similar in appearance to Ventricular Tachycardia?

A. Walking to the bathroom
B. Brushing your teeth
C. Using the remote control
D. Blowing your nose




Question #18

A nurse has just attached a cardiac monitor to a patient and she notes "chaotic electrical activity" on the monitor. It looks like Ventricular Fibrillation. After she makes certain that the patient is responsive, what is the next task she should perform?

A. Call a Code Blue
B. Draw the patient's blood
C. Check the sensor and cable attachments
D. Take a break