Transcript Name That Rhythm-Blocks & stuff 2445KB Jan 14 2015 08:21:51

Name That
Rhythm
EMT-Intermediate
W06
And you thought we
wouldn’t review…..
Heart A & P
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Location
Pieces, Parts
Important Vessels
Electrolyte Role
Pulling apart
waveforms
Valves
&
Vessels
Review of Important
Vessels
The Components
• SA Node
• Internodal
Pathways
• AV Junction
• AV Node
• Bundle of His
• L & R Bundle
Branch
• Purkinje Network
• Purkinje Fibers
The Route
Sino Atrial
Node
• The Natural “Pacemaker”
– Connects directly
to atrial fibers
.04 Sec
• Fires 60-100 times per
minute
• Wavelike Atrial Depolarization
• The P-Wave
0.20 Seconds per 5 Boxes
.04 Sec .04 Sec
.04 Sec
.04 Sec
P-Wave
QWave
P-R Interval
AV Junction
• Receives impulses from
SA Node via the Atrial
Cells
– An electrical funnel
– Impulses hit at various
times
– Causes delay
• PR-I
– Susceptible to blockage
• Path from A to V
– Delivers impulse to the AV
Node
Atrio-Ventricular Node
• Lies between the
Atria and Ventricles
• Collects impulses
from above
• Stimulates
Ventricles
• If unstimulated
– Intrinsic rate 40-60
Bundle of His /
Left and Right Bundle
Branches
• Distributes Impulses from
the Node
• “The Ventricular
Messengers”
Purkinje
Network/Fibers
• Direct connection with
ventricular tissue
• Intrinsic rate 20-40 if
unstimulated
T-Wave
P-Wave
P-R Interval
QRS
Complex
Electrical Conduction
System
• Sympathetic-Thoracic/Lumbar Nerve
– Norepinephrine
•
HR,
Contractility
• Parasympathetic-Vagus Nerve
– Acetylcholine
•
HR (Valsalva)
• Chronotropic-HR
• Inotropic-Contraction
Electrical Conduction
System
• Na+ in & K+ out = Depolarization
• K+ in & Na+ out = Repolarization
– Imbalances in K+ or Na+
• Effects Automaticity & Conduction
• Hypo & hyperkalemia affects irritability
• Ca++ - Depolarization and Contraction
– Affects Contractility
– Hypo & Hypercalcemia effects
contractile force
Phases
• Phase 0 – Rapid Depolarization
– Reached max potential -90mV
– Fast Na+ Channels Open
– Cell now positive +25mV
• Phase 1 – Early Rapid Repolarization
– Fast Na+ Channels Close
– K+ still being lost
– MP approaching 0mV
• Phase 2 – Prolonged Slow Repolarization
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Plateau Phase
Muscle finishing contraction
Beginning to relax
MP staying close to 0mV
Phases
• Phase 3 – End of Rapid Repolarization
– K+ returns to inside
– Cell returns to -90mV
– Almost ready
• Phase 4
– Na+ - K+ Pump turns on
• Sends Na+ out
• Brings K+ in
• Ready to do it all over again now 
Refractory Periods
Excuse me!!! I hate to interrupt again, but, who
cares???
• Absolute Refractory Period
– Polarity of cell prohibits
depolarization
• Relative Refractory Period
– Cell is returning to ready state for
depolarization
– Impulse now is BAD!!!
• R on T Phenomenon
– Causes VT & VF
– Treated with defibrillation
• Can be caused by:
– Frequent PVC’s
– EMT-P not pushing the
“sync” button
QRS Complex
Lead Considerations
• $25,000 mVoltmeter
– Lead Views:
• 1 – Lateral
• 2 – Inferior
• 3 – Inferior
The Six Step Approach
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What is the Rate?
Is the Rhythm Regular?
Are there P-Waves?
Is the P-R Interval Normal?
Is the QRS Complex Normal?
Is There a P-Wave for Every QRS?
Describe What You’ve
Found!!!
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IN GENERAL (underlying rhythms)!!!
What are the abnormalities?
Does it originate in the Sinus Node?
Does it follow through from the Atria
to the ventricles? Are there
abnormal delays?
• What are the exceptions to the
underlying rhythm? (Describe those
also)
Normal Sinus Rhythm
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Rate: 60 - 100
Regularity: Very
P-Waves: Present and Normal
P-R I: 0.12-0.20 sec
QRS: 0.04-0.12 sec and Normal
Married: 1 P: 1 QRS, no extras or shortages
Sinus Arrhythmia
Rate: 60 - 100
 Regularity: Irregular
 P-Waves: Present and Normal
 P-R I: 0.12-0.20 sec
 QRS: 0.04-0.12 sec and Normal
 Married: 1 P: 1 QRS, no extras or shortages
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Sinus Tachycardia
Rate: Over 100
 Regularity: Regular
 P-Waves: Present and Normal
 P-R I: 0.12-0.20 sec
 QRS: 0.04-0.12 sec and Normal
 Married: 1 P: 1 QRS, no extras or shortages
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Sinus Bradycardia
Rate: Less than 60
 Regularity: Regular
 P-Waves: Present and Normal
 P-R I: 0.12-0.20 sec
 QRS: 0.04-0.12 sec and Normal
 Married: 1 P: 1 QRS, no extras or shortages
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Atrial Fibrillation
Rate: Usually tachy
 Regularity: Irregular (Irregularly irregular)
 P-Waves: Not Discernible
 P-R I: Undeterminable
 QRS: 0.04-0.12 sec
 Married: Undeterminable
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Atrial Flutter
Rate: Usually tachy
 Regularity: Atria Regular
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Ventricles May be Irregular
P-Waves: Sawtooth Pattern 2:1, 3:1, 4:1...
 P-R I: 0.12-0.20 sec on conducting beat
 QRS: 0.04-0.12 sec
 Married: P-waves outnumber QRS
 (Picket fence)
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(Paroxysmal) Supra
Ventricular Tach
Rate: 140-220
 Regularity: Regular
 P-Waves: Usually falls within the QRS-T
complex (not visible)
 P-R I: Shorter than 0.12, or absent
 QRS: 0.04-0.12 sec and Normal
 Married: Undeterminable
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SVT
• WPW
– Usually based on Hx.
– Delta wave on Q
– Shortened PR-I
– No Verapamil – Accessory Path use
increase
1st Degree Heart Block
Rate: 60 - 100
 Regularity: Very
 P-Waves: Present and Normal
 P-R I: Longer than 0.20 sec
 QRS: 0.04-0.12 sec and Normal
 Married: 1 P: 1 QRS, no extras or
shortages
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2nd Degree Heart
Block (Type 1)
Wenkebach
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Rate: Can be Normal, or usually brady
Regularity: Irregular
P-Waves: Present and Normal
P-R I: Lengthens until beat is dropped
QRS: 0.04-0.12 sec and Normal
Married: P-wave present on conducting beats,
increased delay causes missed QRS
2nd Degree Heart
Block (Type 2)
Mobitz II
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Rate: Less than 60
Regularity: Irregular
P-Waves: Present, 2:1, 3:1, 4:1
P-R I: 0.12-0.20 sec on conducting beat
QRS: 0.04-0.12 sec, may begin to widen
Married: P-wave for every QRS and extras
depending on conduction ratio
3rd Degree Heart Block (CHB)
Complete Heart Block
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Rate: Ventricular Rate 40-60
Regularity: Atria-Regular
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Vent-Regular
P-Waves: Present and Normal
P-R I: Atria independent of Ventricles
QRS: Usually greater than 0.12 sec
Married: P-waves completely unrelated to QRS
Complexes.
Complete Heart Block
Junctional Rhythm
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Rate: 40-60
Regularity: Regular
P-Waves: Inverted, Retrograde or Absent
P-R I: Shortened or absent
QRS: 0.04-0.12 sec
Married: P-wave for every QRS, sometimes not
visible
Junctional
Junctional Accelerated
Rhythm
Rate: 60-100
 Regularity: Regular
 P-Waves: Inverted, Retrograde or Absent
 P-R I: Shortened or absent
 QRS: 0.04-0.12 sec
 Married: P-wave for every QRS,
sometimes not visible
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Junctional Tachycardia
Rate: 100-140
 Regularity: Regular
 P-Waves: Inverted, Retrograde or Absent
 P-R I: Shortened or absent
 QRS: 0.04-0.12 sec
 Married: P-wave for every QRS,
sometimes not visible
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Ventricular Tachycardia
We’ll look at Torsades de Pointes in Lab
Rate: 100-220
 Regularity: Regular
 P-Waves: None
 P-R I: None
 QRS: Greater than 0.12 sec
 Married: NO
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Ventricular Tachycardia
Ventricular Fibrillation
Rate: No ventricular rate
 Regularity: Irregular
 P-Waves: No
 P-R I: No
 QRS: No, unorganized ventricular baseline
 Married: No
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Ventricular Fibrillation
Asystole
Rate: 0
 Regularity: N/A
 P-Waves: None
 P-R I: N/A
 QRS: None
 Married: No (verify a second lead)
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Asystole
Agonal / Idioventricular
Rate: 20-40
 Regularity: Irregular
 P-Waves: None
 P-R I: N/A
 QRS: Wider than 0.12 sec
 Married: NO (a dying heart)
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Idioventricular
• Less regular than this!
Exceptions /
Disruptions
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Premature Ventricular Contractions
Premature Atrial Contractions
Bundle Branch Blocks
Pacer Considerations (Atrial,
Ventricular or Both)
Premature Ventricular
Contractions
• Wide, Bizarre QRS Complex
• Always identify the underlying rhythm
first
• Can appear in couplets, triplets, short
runs of V-Tach, bigeminy and
trigeminy
• Can be uni-focal or multi-focal
• Caused by random firing within the
ventricles
• Not accompanied by a P-wave
PVC’s
PAC’s
• P-QRS Complex
appearing in an
unexpected location
• Caused by a
stimulus from within
the Atria, but not
from the SA Node
PJC
Bundle Branch Block
• Any rhythm having a BBB will have
a widened twin peaked R-Wave
Paced Rhythms
• Patients may have various types of
pacemakers
• Atrial
• Ventricular
• Both
• Vertical spike on monitor is an
indicator
Paced Rhythms Various
Artifact
• 60 Cycle Interference
• Loose Leads/Moving Ambulance
In Summary
• Really Cool Physiology!!!
• GENERAL RULES to
Interpretation
– Applicable to 3 – lead monitoring
• Practice, Practice, Practice…
• Remember the rules, NOT how it
looks coming from one patient or
one rhythm generator!!!
Sources – In order of
preference
• Many of the pictures and info from:
– Flip and See ECG, 2nd Edition
• Cohn/Gilroy-Doohan
– A great resource
– Paramedic Paramedic Textbook, Revised
2nd Edition
• Mick J. Sanders, Mosby
– ECG’s Made Easy, 2nd Edition
• Barbara Aehlert, RN, Mosby
– Basic Dysrhythmias, Interpretation and
Management, 3rd Edition
• Robert J. Huszar, Mosby