OVERVIEW OF ECG/EKG

Introduction to Electrocardiogram

• It is sometimes referred to as an ECG or an EKG• In the late 1880’s, it was discovered that the electrical

activity of the heart could be monitored through the skin• In 1901, Dutch physiologist Willem Einthoven invented

the electrocardiograph machine, to record the heart’s electrical activity. He identified and named the waveforms produced by the heart’s electrical system– P, Q, R, S, and T

Introduction

• An electrocardiogram or ECG (EKG)– Is a graphic recording of the electrical activity of

the heart. – Converts the heart’s electrical activity into lines

called “Waveforms”• Can be seen on a monitor or printed out on paper

Introduction

• Today, ECG monitoring is used in a variety of settings. It is an important tool that provides vital information including:– Heart rate

• How fast the heart is beating

– Heart rhythm• Whether the rhythm of the heartbeat is steady or irregular

– Conduction abnormalities• The strength, timing, and conduction of electrical signals

as they pass through each part of the heart

ECG Indications

• The ECG is used to detect and evaluate many heart problems such as:– Abnormal heart rhythms• Arrhythmias

– Heart failure• A condition in which the heart can’t pump blood the

way it should

– Heart attacks• Known as an MI or myocardial infarction

ECG Indications

• The ECG is also used to continually monitor how a patient’s heart is working while they are in the hospital if they have a heart related illness or a history of heart disease

ECG Indications

• In some cases, patients may have ECG monitoring even though their main illness is not heart-related. – Some medical disorders and procedures can affect

heart function

ECG Indications

• Indications for cardiac monitoring include:– Myocardial infarction or ischemia– Surgical procedures– Fluid and electrolyte imbalances– Hemorrhage – Drug toxicities– Cardiac history– Trauma– Respiratory illnesses– Kidney failure– Infections

Types of ECGs

• 12-lead ECG

Types of ECG’s

• Rhythm strips

Monitoring ECG’s

• Hardwire monitoring

Monitoring ECG’s

• Telemetry

ECG Equipment

• EKG machine equipment includes the ECG machine, electrodes, paper, and connecting wires

• In order to pick up the electrical activity of the heart, at least three electrodes are placed on the patient’s body and connected to the ECG monitor by the connecting wires– 1 positive, 1 negative, and 1 ground

• When electrical activity occurs in the heart, waveforms are seen on the ECG

ECG Equipment

• Machine

ECG Equipment

• Electrodes– Are applied at specific locations on the patient’s

chest wall and extremities to view the heart’s electrical activity from different angles and planes

Electrodes

• How to apply– Always explain procedure– Expose and privacy– Choosing a site– Gel– Applying new electrodes

Electrodes

• Preparing the skin– Cleaning– Hair

Lead Wires or Cable Connections

• Clip• Snap

Lead System

• In order to pick up the electrical activity of the heart, at least three electrodes are placed on the patient’s body and connected to the ECG monitor by cables– One positive, one negative, and one ground

• A lead refers to the position of the positive and negative electrodes as programmed by the ECG monitor.

• Different leads are used to view the electrical activity at different parts of the heart

• Monitoring systems may have three to six electrodes, which allow for monitoring in several leads simultaneously

Lead System

• 12-lead EKG (Left side)– Chest• V1-V6

– Extremities• RA-RL-LA-LL

• Portable telemetry– Torso

Lead System

• Right Side– ER– Nurse– Reverse V3, V4, V5, and V6 to the right side of the

chest instead of left side of chest• V1 and V2 stay in original position

– Mark “right side” on the ECG print out

ECG Paper and Measurements

• ECG paper – is a graph paper used to measure rates of impulse

formation and the duration of the electrical events that occur in the heart

– Made up of vertical and horizontal lines, which form large and small boxes

ECG Paper and Measurements

• Vertical lines– Measure voltage (measured in millivolts)

• Horizontal lines– Each small box equals 0.04 seconds of time and

each large box equals 0.20 seconds of time

ECG Paper and Measurements

• Some ECG graph paper has markings above or below the graph to mark seconds of time. In the example below, there are markings for every 1 second of time

ECG Paper and Measurements

• Printing– How to?– Entering data– Recording information

Machine Maintenance

• Always plug machine into red electrical outlet when not in use

• Check machine for supplies daily– paper, electrodes, alcohol prep pads, germicidal

wipes• Check all lead wires for breaks• Check electrode clips for intactness

Monitor Problems

• How do you know your limb leads have been placed on the patient correctly?– Artifact– Interference– Wandering baseline– Faulty equipment

• Corrective Actions

Performing 12 Lead ECG’s

• Skill check off as a reference