Week 5 ECG/ EKG Monitoring CH 22 Flashcards
What is the conduction system of the heart?
Includes
SA Node
AV Node
Conduction
Bundle of HIS
Right and Left Bundle Branches
Purkinje Fibers
Depolarization- Stimulation- systole
Repolarization- Relaxation- diastole
What is the pace of the SA node?
60-100 BPM
Junction pace is ?
40-60 BPM
Purkinje System pace is?
30-40 BPM
Failure of one pacemaker allows what to fire?
Subsidiary pacemaker to fire
Name the normal electrical conduction system
SA - sinus node
AV node
Conduction
Bundle of HIS
Right and Left Bundle Branches Purkinje Fibers
Depolarization
Repolarization
SA Node Depolarization includes phase 4 what is happening in this phase?
K channels close, slow NA channels opening
Then Ca channels open
Ca channels close, K channels open
Decrease of Ca permeability
Increase K permeability
Then K channels close, slow open Na channels; slow depolarization - pacemaker potential
Myocardial Action Potential Includes
Na in fast
K out fast
Ca in slow
K out fast
Bipolar Lead placement includes
Lead 1- RA- —– LA+
Lead 2- RA- ——- LL+
Lead 3 LA- ——- LL+
Unipolar Lead placement includes
V1- 4th intercostal space RSB
V2- 4th intercostal space LSB
V3- halfway between V2-V4
V4-V5-intercostal space, midclavicular line
V5- anterior axillary line between V4 and V6
V6- midaxillary line, level with V4
Opposite with right sided ECG
EKG graph contains a background pattern of horizontal and vertical lines
that form 1mm small boxes and 5 mm larger boxes
True
The vertical axis on ECG measures?
Voltage/ Amplitude
Vertically measured - 1 small box equals 0.1 mV
What does horizontal y axis measure on EKG?
Measures time
1 small box on EKG equals?
0.04 seconds or 40 ms
5 small boxes =
1 Large box = 0.20 seconds or 200 ms
25 small boxes =
5 large boxes= 1 second or 1000 ms
Printing a rhythm strip that is 6-12 seconds long makes it easier to calculate what
HR whether it is regular or irregular using the 6 second method
Atrial depolarization is represented by?
The P wave
QRS is represented by?
Ventricular Depolarization
T on the EKG is represented by?
Ventricular repolarization
Different interval measurements include
P-R
Q-T
S-T
PR interval is
0.12-0.20 s
Starts beginning of P wave to beginning of flat line of Q
QRS interval is
0.06-0.12 s
Measured Flat line of Q beginning to of Flat line of S
QT interval is
0.36-0.44s
Measured Flat line beginning of Q to end of T wave
PR segment is measured from
End of p wave to flat line beginning q
ST segment is measured from
Flat line of S wave to beginning part of T
The first small wave upright seen on EKG
P wave
This wave represents discharge of the SA node and depolarization of both atria
P wave
Small, smooth, and rounded
Should be a P wave preceding each QRS complex 1:1
Reflects the period of time required for the cardiac conduction impulse to travel from the atria to the ventricles
PR Interval
Should be constant
_____ wave is first negative deflection below the isoelectric line
Q wave
______ wave is first upward or positive deflection
R wave
_____ wave next negative deflection immediately after the R wave
S wave
What represents ventricular depolarization?
QRRS complex
Rounded upward deflection immediately after the QRS complex
Signifies ventricular repolarization
T wave
Small rounded upright wave after the T wave
Represents the repolarization of the Purkinje fibers of the heart
Usually not present
Most frequently seen in slow rhythms
U wave
Begins with the end of the QRS complex and ends at the start of the T wave
ST Segment
This represents the time between the end of the ventricular depolarization and the beginning of ventricular repolarization
ST Segment
The normal _________ segment is flat isoelectric relative to the T-P
ST
This measurement represents the total activity of the ventricles
Q-T Interval
How is HR calculated?
R to R interval
60-100 Normal
Less than 60 Brady
More than 100 Tachy
QT Interval can be either short or long
True
How to interpret rhythm strip
P
- Is it same size, shape, and direction
- 1 per every QRS
R-R Interval
-Reg or ireg
- Rate
PR Interval
- 0.12-.20
QRS Complex
Less than 0.12 seconds
all same shape
Then QT Interval
- 0.36-0.44
Use EKG calipers
Initial approach analysis for EKG includes what?
- P waves?
- Rate?
- Rhythm?
- QRS normal or wide?
Name Atrial Rhythms
SR/SB/ST
Sinus Arrhythmia
Sinus pause/ arrest
PACs
SVTs
Rhythm: Regular
Rate: 60-100
P waves: One every QRS all same shape, size, and direction
QRS Complex: less than 0.12 sec and all the same shape
Pacemaker is SA Node
NSR
Rhythm: Regular
Rate: Less than 60 BPM
P waves: One per every QRS all same
PR: WNL
QRS: less than 0.12 and all the same
BSR
Pacemaker is SA Node
What causes Sinus Brady?
Adults and children asleep
Common in well conditioned athletes
Present in up to 35% people under 25 while at rest
MI
Vagal Stimulation
Medication
Diseases of SA Node
Rhythm: Regular
Rate is 100- 160BPM
P wave one per every QRS
PR: WNL
QRS: Less than 0.12
Pacemaker is SA node
Sinus Tachy
What causes Sinus Tachycardia?
Acute MI
Caffeine
Dehydration
Drugs
Exercise
Fear and anxiety
Fever
HF
Hyperthyroidism
Hypoxia
Infection
Meds
Nicotine
Pain
PE
Shock
Sympathetic Stimulation
Rhythm Irregular
Rate usually normal
P waves : WNL
PR: WNL
QRS Complex less than 0.12 ad all same
Pace is SA Node
Sinus Dysrhythmia
When the SA node fires irregularly it is called
Sinus Arrhythmia
Associated with the phases of breathing and changes in intrathoracic pressure
Respiratory Sinus Arrythmia
Not related to the ventilatory cycle
Non resp sinus arrhytmia
Rhythm: Irregular but underlying is regular
Rate Normal but may be slow
P waves WNL
PR Interval: 0.12-0.20 second and constant
QRS Complex: Less than 0.12 second and all the same shape
Sinus Pause/ Arrest
Disorder of impulse formation
Sinus impulses are not generated
Results in absent PQRST
Sinus Arrest
What causes Sinus Arrest?
Damage to or a disease of the SA Node
-CAD
- MI
- Rheumatic Disease
Carotid Sinus Pressure
- Sudden increase in parasympathetic activity on SA Node
- Stimulation of the pharynx
- OBSA
- Hypothermia
- Reactions to medications
What do I do about Sinus Arrest?
No tx if episodes are transient and there are no significant symptoms
Sinus Arrest with hemodynamic compromise present
Possible Atropine
Possible Temporary Pacing
If episodes of Sinus Arrest are prolonged and frequent as result of SA Node disease then?
Insertion of pacemaker may be warranted
Rhythm: Regular
- PACs interrupt the rhythm making it appear irregular
Rate: 60-100 BPM
P Waves: Present and premature
- One every QRS
- May be flattened
PR: Normal or slightly abnormal
QRS: Less than 0.12 second and all the same shape
PAC
Occur when an irritable site within the atria discharges before the next SA node impulse due to discharge
PACs
P wave of PAC may be what?
Biphasic
Flattened
Notched
Pointed
Lost in preceding T wave
Rhythm: Regular
Rate: 100-250 BPM
P Waves: Present but may be buried in T waves commonly pointed
QRS: WNL
SA NODE Pace
Atrial Tachycardia
Rhythm: Generally regular but can be irregular
Rate: Varies, Controlled less than 100, Uncontrolled greater than 100
P waves: Multiple for every QRS
P wave never stops and overlaps other waves
PR Interval: Unmeasurable
QRS: less than 012
Atrial Flutter
Rhythm: Irregular
Rate: Varies: Controlled less than 100, uncontrolled greater than 100
P waves: Wavy baseline. Looks like artifact
PR: Unmeasurable
QRS: less than 0.12
A Fib
Name the most common type of SVT and is caused by reentry in the area of the AV Node
AVNRT
Fast pathway is Beta
Slow Pathway is Alpha
How do you recognize AVNRT?
Ventricular rhythm is usually regular
150-250 BPM
P waves- Hidden in QRS complex, Ventricles stimulated then atria then it will show negative p wave after the QRS in lead II, III, and avF
When atria is depolarized after the ventricles, the p wave typically distorts the QRS
AVNRT what causes it?
Common in individuals with no structural disease
Triggers
- Hypoxia
- Stress
- Anxiety
- Caffeine
- Smoking
- Sleep Dep
- Many meds
AVNRT can also occur in individuals with
COPD
CAD
Valvular Heart Disease
Heart Failure
Digitalis Toxicity
Stable pt with AVNRT, what do you do?
Apply pulse ox
Administer supplemental O2
Establish IV
Administer sedation
Unstable pt with AVNRT?
Synchronized Cardioversion
Someone has atrial tachycardia, what do you do?
If symptomatic with rapid rate then
Vagal maneuvers
Adenosine drug of choice
Calcium channel blockers
Beta Blockers
Synchronized cardioversion if hemodynamic compromise present
Delivery of an electrical shock to the heart timed to occur during QRS
Synchronized Cardioversion
Why would someone use cardioversion?
Some unstable narrow QRS Tachys
Unstable
- AFIB
AFLUTTER
Monomorphic VTACH
Ventricular beat is the
Purkinje System 30-40 BPM
Junction is
40-60 BPM
SA- 60-100 BPM
Rhythm: Regular except for premature beat
Rate: Depends on underlying
P wave: may not be seen may be inverted in lead II,III, and aVF
may precede follow or be buried
PR: 0.12 or unmeasurable
QRS: less than 0.12
PJC
Rhythm: Regular
Rate: 40-60 BPM originating in the AV junction
P waves: May not be present. in lead II,III, and aVF
may precede follow or be buried
PR Interval: 0.12 or not measured
QRS: Less than 0.12
Junctional Rhythm
Rhythm: Regular
Rate: Greate than 100 BPM usually 130-180 Originating in AV
P waves:May not be present. in lead II,III, and aVF
PR Interval: Less than 0.12 or unmeasured
QRS: Less than 0.12 sec
Junctional Tachycardia
Heart blocks originate where?
Junction or bundle
All charcteristics of NSR except PR is more than 0.20 sec
Originates in SA node
1st Degree AV Block
Rhythm: Irregular. P waves will map out. Ventricular rhythm is irregular.
Rate: Ventricular rate. Will be less than atrial rate.
P waves: Upright round. Lose 1:1 ratio. Will have dropped QRS
PR Interval: Gradually lengthens then QRS dropped
QRS Complex: Less than 0.12 sec.
2nd Degree AV Block Type 1
Mobitz 1 or Wenckeback
Rhythm: Can be regular or irregular
Rate: Frequently slow.
P waves: Present, march out. Lose 1:1 ratio. More P’s than QRSs
PR Interval: Present on conducted beat and constant. May be normal or prolonged
QRS: Usually slightly wide greater than 0.12 sec
Second Degree AV Block Type 2
Mobitz II
Rhythm: Atrial regular, P waves march out. Ventricular rhythm, QRS march out and not in sync
Rate: Slow. Dependent on secondary pacemaker (junctional or ventricular)
P Waves: No true PR since the atria and ventricles are independent
QRS: Normal or wide
Narrow- Junctional
Wide- Ventricular
3rd Degree
Rhythm: PVC interrupt rhythm
Rate: Underlying rhythm
P waves: None or not related to QRS
PR Interval: None
QRS: Wide and bizarre. Greater than 0.12
PVCs
PVCs how do you recognize them?
Multiform PVCs appear different from one another in the same lead
Often not always though arise from different anatomical sites
What causes PVCs?
Acid Base imbalance
Acute coronary syndromes
Cardiomyopathy
Digitalis Toxicity
Electrolyte Imbalance
Exercise
Heart Failure
Hypoxia
Increase in catecholamines and sympathetic tone medications
Normal variant
Stimulants
Valvular heart disease
Ventricular Aneurisym
Rhythm: Regular, can become irregular
Rate: 100-250
P waves: None
PR: None
QRS: Greater than 0.12 wide and bizarre
VTACH
Code Blue= No pulse
Rapid: With a pulse
Rhythm: Regular or irregular
Rate: 150-300, typically 200-250 BPM
P waves: NONE
PR Interval: NONE
QRS Complex: Greater than 0.12 sec changes direction and twists
Torsades de Pointes
Rhythm: Irregular
Rate: 0BPM
P waves: NONE
PR: NONE
QRS: Not clear
CODE BLUE
VFIB
Rhythm: Usually regular, may become irregular
Rate: 20-40 BPM can be slower
P waves: None
PR: None
QRS: Greater than 0.12
T wave opposite direction as QRS
CODE BLUE
Idioventricular Rhythm
V Escape
Rhythm: Regular
Rate: 40-100 BPM
P waves: Usually absent
PR Interval: NONE
QRS Complex: Greater than 0.12 sec
T wave opposite direction as QRS
Accelerated Idioventricular Rhythm
Rhythm: NONE
Rate: 0 BPM
P waves: None
PR: None
QRS: None
Asystole
Code blue
Transvenous Pacemakers are at
Internal jugular vein
Brachial vein
Also, there are implanted Pacemakers
One spike producing an abnormal P wave followed by a normal QRS
Atrial Pacemaker single chamber
One spike producing a wide QRS
Ventricular Pacemaker
One spiked followed by an abnormal P followed by a second spike producing a wide QRS
AV Sequential Pacemaker Dual Chamber
Name complications of Pacemaker Use
Infection
Bleeding
Dislocation of lead
Skeletal muscle or phrenic nerve stimulation
Cardiac tamponade
Pacemaker malfunction
Monitoring ECG strips should be documented every
4hrs
in the CICU or CCU
8 hrs in tele
ED- Obtain initial ECG on pt with suspected cardiac event and document rhythm interpretation in record
ECG Monitoring
ANY
Dysrhythmias
Change in conduction
New ST Segment elevation or depression
Document on the strip of any treatment
Follow strip after therapeutic intervention
ECG monitoring
PR interval measurement
QRS duration
Rhythm interpretation
Nurse signature
Clinical Symptoms/ Signs of pt deteriorating status
HR less than 40 or greater than 130 if it is change for pt
SBP less than 90
RR less than 8 RR or greater than 30
O2 less than 90% at 2L more than baseline oxygen use
Acute change in LOC
Acute change in oxygen and needs FiO2 50% or greater
New, repeated, or prolonged seizures
Care of Patient with Dysrhythmia
Cause of it, factors, effect on the heart
health Hx, previous occurrences of decreased cardiac output, possible causes of dysrhythmias
Psychosocial assessment, pt perception of dysrhythmias
Assess indicators or cardiac output and oxygenation
All medications
Physical Assessment includes
Skin pale and cool
Signs of fluid retention
Rate, rhythm of apical, peripheral pulses
Heart sounds
BP and pulse pressure
Nursing Diagnoses include
Decreased cardiac output
Anxiety
Deficient knowledge of
Collaborative problems and potential complications
Cardiac arrest
HF
Thrombotic event, especially a fib
Nursing process care for pt with dysthymias Planning and goals
Eradicating or decreasing occurrence of dysrhythmias to maintain CO
Minimizing anxiety
Acquiring knowledge about dysrhythmias and its Tx
Nursing Interventions include
Monitor ECG and manage
Reduce anxiety
Promote home and community care
Educate pt about self-care
Continuing care
Nursing interventions
Assess VS ongoing
Lightheadedness, dizziness, fainting
If hospitalized
- Obtain 12 lead ECG
Continuous monitoring
Monitor strips
Antiarrhythmic Medications
- 6 min walk test
Nursing Intervention Minimize Anxiety
Stay with pt
Maintain safety and security
Discuss emotional response
Help develop system to identify factors
Maximize the pt control
Nursing Intervention Promote Home and Community Based Care
Educate pt on
Tx options
Med levels of therapeutic range
How to take pulse before med
How recognize symptoms of dysrhythmias
Measures to decrease recurrence
Plan of action in case of emergency
CPR
Evaluation Nursing process for pt with dysrhythmias
Maintain CO
-stable vs, and no signs of dysrhythmia
Decrease of anxiety
- Positive attitude
Express understanding of tx of dysrhythmias
