Dysrhythmias Flashcards
parasympathetic influence on heart
Lowers HR
Slows impulse conduction
Decrease force of contraction
Sympathetic influence on heart
Increases rate and force of contraction
SA node
above right ventricle
60-100bpm
AV node
In the right ventricle
40-60bpm
Purkinje fibers
20-40bpm
3 electrode system
White: Right upper chest
Black: Left upper chest
Red: Left lower chest
WHITE ON RIGHT, SMOKE OVER FIRE
5 electrode system
same as 3 electrode plus
Brown right lower sternum
Green lower right (equidistant from red)
12 lead EKG placement
4 on limbs
V1 starts just right of mid sternum then kinda makes a line going diagonal and down to the left.
V2 at just left of mid sternum
V3 just up and right of apical pulse spot
V4 at apical pulse
V5 at intercostal space to left of apical pulse
V6 1 rib lower and to the left of V5. Will kind of be on the side.
How to determine BPM from ECG
Count number of R waves (tall guys) for 6 seconds
multiply that number by 10
How can you tell how long 1 second is in an EKG
5 squares
1 square =.2 seconds
ECG measurements (time)
PR interval: .12-.2seconds
QRS complex: .06-.12
QT interval: .34-.43
Normal sinus rhythm
Atrial and ventricular rate: 60-100bpm
Rhythm; regular
QRS shape and duration: Normal
P wave: Normal and consistent, always before QRS
PR interval: Consistent between .12-.2 seconds
P:QRS ratio: 1:1
If no P wave think
ATRIAL ISSUE
A fib or flutter
How to determine ventricular rate
number of QRS in 6 seconds x 10
Determine atrial rate
number of P waves in 6 seconds x 10
What should the ratio of atrial rate: ventricular rate be
1:1
Sinus bradycardia
1:1 P:QRS ratio
regular rhythm
PR interval 0.12-0.2 seconds
QRS interval: <0.12 seconds
Sinus bradycardia treatment
Assess if pt is symptomatic
With hold beta blockers
Admin Atropine every 3-5 min if pt is symptomatic
For transcutaneous pacing use defib
Turn to pace mode
Sinus Tachycardia
Between 100-180bpm
P:QRS ratio 1:1
Regular rhythm
PR interval 0.12-0.2 seconds
QRS usually normal <0.12 seconds
Sinus Tachycardia treatment
Assess if symptomatic
Watch for reduced CO from lower diastolic fill time
If ST prolonged = BAD
Give:
- Beta blockers
- Calcium channel blockers
- Catheter ablation of SA node
- Fluids
- Antipyretics
Atrial flutter
Sawtooth shaped
Rapid regular atrial rate between 200-350/min
Associated w/CAD, HTN, valve disorders, pulmonary embolism
PR interval variable and not measurable
QRS normal
Give anticoagulants due to risk of throwing clot
Treatment goals for atrial flutter
Calcium channel and beta blockers, antidysrhythmics
Catheter ablation
Atrial fibrillation
Loss of atrial contraction
Risk of stroke and death
Atrial rate 30-600
Ventricular rate 120-200
Atrial and ventricular rhythm highly irregular
NO P WAVE
PR interval can’t be measured
P:QRS ratio: Many:1
QRS shape and duration: usually normal
Goals of A fib treatment
Decrease ventricular response
prevent stroke
Convert to sinus rhythm
Calcium channel blockers, digoxin, beta blockers, amiodarone
Watch for clots thrown, anticoagulants
Acute afib interventions
Determine onset
Anticoagulants:
-Heparin, warfarin
TEE (Transesophageal endocardiography)
Cardioversion
Chronic Afib interventions
Long term
Anticoagulants
INR 2.0-3.0
aPTT 1-1.5x control
anti arrhythmics
Cardioversion
AV node ablation
Rapid ventricular response from AFIB interventions
Symptomatic if over 100
Determine onset and cause
anticoags
Cardioversion
Beta blockers
Watch for infection
EKG differences between Flutter and fibrillation
Flutter:
Swtooth, lots of sharp points up
Fibrillation:
-Squigglies betwen QRS waves, no P waves
Premature ventricular contraction
Impulse starts in ventricle before next normal sinus impulse
P:QRS 0:1 or 1:1
P wave may be absent
PR interval: If P wave exists then under 0.12 seconds
QRS shape: Wide and bizare
Can be caused by caffeine, nicotine, alcohol
Abnormal causes: ELECTROLYTE IMBALANCE (Mag, Potassium)
Premature ventricular contraction manifestations
May feel nothing, or skipped beat
Usually not serious
Frequent PVCs treated w/ long term meds :
- Solatol
- amiodarone
If too frequent, or MI then Lidocaine may be used
NOTIFY MD IF 3 PVC IN A ROW OR MORE THAN 6 IN A MINUTE
Ventricular tachycardia
3+ PVCs in a row
BPM over 100
WIDE QRS under 0.2 seconds
No PR interval
Can’t determine PQRS
Determine if pulse or pulseless!
Caused by MI
If ventricular tachycardia has pulse what do you do
Cardiovert
Anti-arrhythmics
Lidocaine
Determine cause
What does VT look like on EKG
Super big sawtooths down
nipples up top
Ventricular fibrillation
Ventricular rate over 300bpm
Extremely irregular rhythm, no pattern
QRS: irregular
Ineffective quivering of ventricles
No atrial activity on ECG
Cardiac arrest
Most common cause CAD resulting in MI. untreated VT cardiomyopathy
DEFIBRILATE
Vfib EKG patterns
looks like pure sawtooth no QRS or really anything
Cardioversion vs defibrillation
Cardioversion: -Delivers low joule shock -Synchronized on R wave -No metal, med patches, or nipples Yell CLEAR
Cardioversion rhythms: (PULSE ONLY)
- Afib
- A flutter
- SVT
- Vtach
Defibrillation:
- High joule shock
- Unsynchronized
- No metal, med patches, or nipples
- Yell CLEAR
Defibrillation rhythms: (PULSELESS ONLY)
V-Tach
V-Fib
Torsades (V-fib)
Who is Implantable cardioverter defibrilator (ICD) for
For patients that :
-survived SCD aka MI
- Spontaneous sustained V tach
- Syncope with inducible V tach/V fib.
- High risk for future life threatening dysrhythmias (QT prolongation)
