EKG CMA Review

Circulation

superior & inferior venal cava→ right atrium → tricuspid valve → right ventricles → pulmonary valve → pulmonary arteries → lungs gas exchange →pulmonary veins → left atrium → bicuspid valve → left ventricles → aortic valve → aorta → arteries → arteroles → arteriol capillaries →gas exchange → venous capillaries → venules → veins → superior and inferior venal cava

Pathways for Conduction

SA node → AV node → Bundle of His → Bundle Branches → Purkinje fibers → interventricular septum → left bundle branch → right bundle branch → apex

SA node

Located in upper right portion of right atrium

initiates the heartbeat

pacemaker of the heart (60-100 bpm)

normal conduction begins in SA node

AV node

located on the floor of the right atrium

causes delay in the electrical impulse, allowing for blood to travel to ventricles

Can act as pacemaker if SA node is not working (40-60
bpm)

Bundle of His (AV bundle)

Located next to the AV node

Transfers electrical impulses from the atria to the
ventricles via bundle branches

Bundle Branches

Split the electrical impulse down the right and left side

From interventricular septum, the impulse activates
myocardial tissue, causing contraction

Contractions occur in left-to-right pattern

Purkinje Fibers

Electrical pathway for each cardiac cell

Impulse activates left and right ventricles simultaneously

Produce an electrical wave

unique qualities of the heart

Automaticity- heart’s ability to generate an electrical impulse

Conductivity-ability of myocardial cells to receive and conduct electrical impulses

Contractivity- ability of the heart muscle to shorten in response to an electrical impulse

Excitability-ability of the heart to respond to an impulse or stimulus

Autonomic Nervous System

Speeds up or slows down the heart rate

\
Sympathetic branch can increase the heart rate (norepinephrine)

\
Parasympathetic branch can decrease the heart rate (vagus nerve)

Depolarization

State of stimulation, preceding contraction

Electrical activation of heart cells

Causes the heart to contract

Most important electrical event

Repolarization

State of cellular recovery, following contraction

Cell returns to a resting state

Heart relaxes, allowing for refilling of the chambers

EKG Waveform

Standardized graph paper used

Paper runs at a standard speed of 25mm/second

Normal amplitude is 10 mm or 1 mv

P Wave

First positive deflection

Occurs when the atria depolarize

Small compared to other ECG waves

Q Wave

Represents conduction of impulse down the interventricular septum

First negative deflection before the R wave

Not always visualized on the ECG

Less than 1/4 the height of the R wave

R Wave

First positive wave of the QRS complex

Represents conduction of electrical impulse to the left ventricle

Usually easiest to find

S wave

First negative deflection after the R wave

Represents conduction of electrical impulse through both ventricles

QRS complex

Represents complete ventricular depolarization

ST segment

Indicates end of ventricular depolarization and beginning of ventricular repolarization

Elevated ST segment indicates myocardial damage (ischemia-reduced oxygen to heart muscle) - STEMI

T wave

Represents ventricular repolarization

U wave

Represents repolarization of Bundle of His and Purkinje fibers

Presence can indicate an electrolyte imbalance

PR interval

Measured from beginning of P wave to beginning of QRS complex

the time that the electrical impulse is initiated until the ventricles are stimulated by the impulse to start the contraction.

QT interval

Time required for ventricular depolarization and
repolarization to occur

R to R interval

Measurement of time from start of one QRS complex to start of next QRS complex

Used to calculate heart rate

Readily seen on ECG

Electrocardiogram

machine that records and electrocardiogram

12 views (12-lead) of the heart at once

10 wires are attached to the body

Telemetry

constant monitoring of the patient in a hospital setting

Stress Testing

Must have emergency equipment available during testing

Patient is attached to the EKG while exercising (bike or treadmill) to see how the heart handles the stress

Thallium can be used for patients that cannot exercise

CMA role – attach leads, monitor v/s

Stress Testing pt edu

Wear comfortable walking shoes

Wear a separate shirt and pants – to access chest for leads

\
Take regular medications the day of stress test

Do not eat a large meal prior to the test

Holter Monitor

Patient will wear monitor for 24 hours or more (as ordered by provider)

Holter records all EKG activity for that time period

Patient will press a button when symptomatic (syncope, pain, palpitations) and keep a diary of all activity

CMA role – attach leads, patient education

Holter Monitor pt edu

Do not remove or replace electrodes

Do not shower or get device wet

Avoid exposure to electrical forces such as metal detectors

Conduct normal activities while wearing

Return at designated time for removal

Preparing the pt

Patient removes clothing from the waist up

Provide with drape, sheet, or hospital gown with \n opening in the front

Patient removes jewelry that may interfere

All electronic devices should be turned off and \n removed

Position patient comfortably on back and provide pillow for head and knees, if preferred

Work from patient’s left side if possible

Ensure privacy

Ensure that arms and legs are supported

Place patient in semi-Fowler’s position if SOB

Provide sheet or blanket to prevent chills

Make sure bed/exam table is not touching wall or \n electrical equipment

Ensure that patient is not touching metal

Make sure there is plenty of paper in machine

Verification

Patient name/date of birth

Location/date/time of recording

Patient age/sex/race/cardiac medications

Height and weight

Reason for exam

Communication

Identify the patient

Check the patient name, identification number, and \n date of birth (two forms of identification)

Introduce yourself and explain what you are going to \n do

Answer all questions

If the patient refuses the ECG, determine the cause. \n Let them know that there is no “electricity”. It is like a \n photo.

Notify your provider if you cannot resolve the problem

Anatomical Landmarks

Midclavicular Line- Usually starts in the center of clavicle and passes through nipple line

also there’s : Anterior axillary line, Mid-axillary line, ntercostal spaces (ICS), Suprasternal notch, Angle of Louis

Limb Leads

Place on fleshy areas in same general vicinity (amputations, etc.)

Sky (white) over grass (green)

Smoke (black) over fire (red)

Bipolar leads

Leads I, II, and III are bipolar – records impulses that travel from a negative to positive pole

Unipolar leads

AVL, AVR, and AVF – unipolar

Precordial Leads

Precordial leads – located on the chest in \\n front of the heart

V1, V2, V3, V4, V5, V6

Where V1-V6 are placed

V1 - V2 - V4 - V3 - V5 - V6

Applying the Electrodes

Prep the skin with either an alcohol swab or electrolyte pad

Shave hair if necessary, or clip hair for continuous \n monitoring

*FOR FEMALES*

lift left breast and place electrodes in \n closest position possible. Do NOT place electrodes on \n top of breast tissue

Non-standard location of electrodes must be \n documented on recording

Limb electrodes

Place on wrists or upper arms and inside of lower \n legs. Location of left and right leads must match.

*Alternate site*: shoulders (deltoid), upper legs, lower \n abdomen

Troubleshooting

P: Electrodes will not stick

S: Cleanse skin with alcohol pads and pat dry and/or clip or shave hair from the site only if necessary

Applying the leads

*Chest leads* = Electrode tabs point toward feet

*limb leads* = Arm electrode tabs point toward feet and Leg electrode tabs point toward hands

Safety and Infection control

Follow universal precautions

Wash your hands

Wear gloves when exposure to blood or bodily fluids is \n likely

Make sure the procedure is performed on the correct \n patient

Raise bed rail if available

Pull out extension for legs and feet if using an exam \n table

Check grounding plug for security

Ensure that bed or table is not touching wall or electrical equipment

Ensure that patient is not touching bed rail, exam table frame or safety rail

Check insulation wires for cracks

Artifacts (somatic tremor)

Large spikes caused by muscle movement

Causes: shivering, muscle tension, pain, fear, talking, \n chewing gum, disorders such as Parkinson’s disease.

Artifacts (wandering baseline)

AKA baseline shift

Usually caused by improper electrode application. \n Can also be caused by poor skin prep, pulling on \n electrodes, old electrodes or clips, oil, lotion, dried out \n electrodes

Artifacts (AC interference)

Small, uniform spikes caused by electricity radiated \n from other machines

Common sources include improper grounding, lead \n wires crossed, corroded or dirty electrodes

Other interrrupted baselines

Loose or unplugged lead

Switched wires

Broken wires

How to calculate the heart rate

ONLY method that can be used with an irregular rhythm

Multiply the number of complexes by 10

Do not count incomplete complexes

Reporting Results

Follow your facility’s policy

Make copy, if required

Fax tracing, if required

if ordered stat, immediately give tracing to your provider

Equipment

Keep machine clean to prevent infection and present \n professional image

For disposable electrodes, clean alligator clips and \n check for paste/gel

Disinfect cables and reusable electrodes

Wash straps; replace cracked/broken straps

Wash reusable electrodes to prevent gel/paste buildup

Scour reusable electrodes once a week

Wipe patient cables and lead wires with damp cloth

Replace cracked or broken wires

Store neatly

NSR (normal sinus rhythm)

All measurements are within normal limits

The rate is between 60 – 100 bpm

There is a P wave indicating that the rhythm started in the SA node (sinus)

Arrhythimas

AKA dysrhythmia

A change from normal sinus rhythm

Can be rate, appearance, or conduction problems

SInus Bradycardia

Sinus rhythm – normal P wave present, other measurements WNL

Rate

Sinus Tachycardia

Sinus rhythm – normal P wave and other measurements WNL

Rate > 100 bpm

Sinus Dysrhythmia

Sinus rhythm – P wave present, other measurements WNL

Slight irregularity in rhythm – usually associated with breathing patterns

SInus Arrest

Normal Sinus Rhythm when complexes are present – consistent pattern

A break in the pattern is sinus arrest

The SA node fails to fire

Not significant unless lasts longer than 6 seconds

Atrial Flutter

Atria are contracting at a rapid rate –much faster than the ventricles are contracting

Sawtooth appearance of “F” waves (may look like P waves)

Consistent ratio (ex. 4 F waves to 1 QRS)

Regular rhythm - pulse

Atrial Fibrillation (A-fib)

No organized contraction of the atria

Quivering state

Blood clots can develop due to stagnation of blood

Irregular rhythm and pulse

Ventricular Fibrillation

OMG rhythm! \n Immediate intervention needed – no pulse being generated – begin CPR

Patient will NOT be conscious

Ventricles are quivering – no wave forms on EKG \n Needs defibrillation (AED)

Asystole

OMG rhythm!

No heart electrical activity or pulse

Heart has stopped – Begin CPR

Patient will NOT be conscious. If talking, check your cables.

Junctional Dysrhythmia

Negative P-waves indicate a Junctional Rhythm

The impulse is generated in the AV node instead of the SA node.

Junctional rhythms may not have a P-wave at all

Rate is often between 40-60 bpm

Premature Ventricular Contractions (PVC)

If the QRS is “wide and bizarre”, suspect a ventricular arrhythmia.

Occasional PVC’s are common and can be insignificant. Usually asymptomatic.

Can occur in pairs, be unifocal, multifocal, or occur in runs

Notify provider if PVC noted on EKG

Anemia (blood diseases & treament)

an inadequate number of red blood cells

aplastic anemia

destruction of bone marrow

sickle cell anemia

chronic genetic anemia

Aneurysm

ballooning out of saclike on the wall of the artery

Arteriosclerosis

hardening of the walls of an artery

Atherosclerosis

Fatty plaques, cholesterol deposited on the walls of arteries

Atherectomy

a balloon is inserted in the vessel, a cutting tool used to clear plaque

CABG (Coronary artery bypass graft)

vein from the leg is implanted on the heart to bypass a blockage in the coronary artery

Congestive heart failure

Heart muscles cannot pump adequately to meet the needs of the body

Treatment: cardiac drugs and diuretics

Embolis

a foreign substance in the blood stream

Hemophilia

Inability to effectively form clots in the blood

High blood pressure

systolic pressure above 140-150

diastolic pressure above 90

Angina

narrowing of the coronary arteries which causes ischemia

Nitroglycerin

treats angina

Myocardial infraction

heart attack

Phlebitis

inflammation of the vein, usually the leg

Varicose veins

dilated swollen veins that have lost elasticity

Productive cough (respiratory diseases & treatments)

wet cough

**Nonproductive cough**

dry hacking

Treatments for coughs: Antitussives, expectorants

**COPD**

**chronic obstructive pulmonary disease aka asthma**

**chronic bronchitis**

inflammation of the bronchi and bronchial tubes persisting over a long time

Emphysema

enlargement of the alveoli and progressive loss of lung function due to destruction of the alveoli

SRS (smoker’s respiratory syndrome

damage caused by smoking that causes chronic symptoms like coughing, wheezing, hoarseness, difficult breathing, and infections

Epistaxis

Nosebleed

Influenza (flu)

highly contagious viral disease

Laryngitis

inflammation of larynx and vocal cord

lung cancer

mainly due to smoking

Pleurisy

inflammation of the pleura

Pneumonia

inflammation/infection of the lung with fluid in the alveoli

Rhinitis

inflammation of the nasal mucous membrane

Sinusitis

inflammation of the mucous membrane of the sinuses

Upper respiratory infection (URI)

aka common cold

inflammation of the mucous membranes of the respiratory tract

Pertussis

whooping cough

Atelectasis

partial or complete collapse of the lung due to the alveoli becoming deflated or filled with fluid

Bronchitis

inflammation of the lining of the bronchial tubes

Legionnaires’ disease

severe form of pneumonia by a bacteria called legionella

Pulmonary edema

excess fluid in the lungs

Pulmonary embolism

A blockage in one of the pulmonary arteries in the lungs