Unit 8: Cardiac Dysrhythmias Flashcards
What is the cardiac conduction system?
SA node: 60-100
AV node: 40-60
Bundle of His <40
Bundle branches 20-40
Purkinje fibers 20-40
What is the normal PR and QRS intervals?
PR (3-5 boxes) .12-.20
QRS (1-3 boxes) 0.4-0.12
p-waves are associated with atrial rate
QRS are associated with ventricular rate
Where do the leads go for a 3 and 5 lead ECG?
3, 5 Red - lower left
3, 5 Black - upper left
5 Green - lower right
3, 5 White - upper right
5 Brown - heart
What is A-fib? Tx?
S/S: decreased urine output, fatigue, SOB, fluid retention
Watch for clotting
Tx: blood thinner, cardioversion, ablation
What is A-flutter? Tx?
Consistent inconsistencies between even QRS complexes
Same as A-fib
What is NSR? Tx?
HB 60-10
Normal intervals
What is bradycardia? Tx?
Risk Factors: hypothyroidism, vagal maneuvers, post-surgery, athletic
Tx: atropine 3x/5min – this wont work for heart transplant patients; 2nd line of tx is dopamine and pacing
What is V-tach? Tx?
Looks like tomb stones
Pulse: cardioversion, amiodarone (300mg then 150 mg), adenosine
Pulseless: lidocaine, defibrilate, CPR, Epi, Amiodarone
What is SVT? Tx?
Risk Factors: caffeine may be normal in adults
S/S: anxiety, light-headed, angina
P-waves are buried in T-waves
Tx: vagal maneuvers, cardioversion (unstable SVT), and adenosine (raise arm for faster delivery)
What is 1st degree heart block? Tx?
Long PR intervals, no treatment given unless poor perfusion is present
What is V-fib? Tx?
These never have a pulse
Defibrilate
Epi and amiodarone
For chronic v-fib, an ICP (automatic shocker) can be placed
What is tachycardia? Tx?
Risk Factors: fever, hypoxemia, hypovolemia
Tx: beta blockers
What is 2nd degree HB? Tx?
Mobitz I
- longer, longer, longer, drop.
- Tx: beta blockers, pacing if symptomatic
Mobitz II
- PR consistent, sometimes QRS doesn’t show up
- Tx: pacing - could lead to 3rd degree
- QRS is wide and ugly when present
What is 3rd-degree HB? Tx?
PR and QRS intervals don’t align, but both are individually consistent.
Tx: pacing
How to recognize pace maker on 6-sec strip?
Dashes on strip before P or QRS complex
What is PVC? Tx?
Normal in adults
Could lead to SVT if there are 3+ in a row
Big, ugly QRS, which comes early
Tx: Calcium channel blocker, beta blocker, amiodarone
IF there are 3+ PCV with tachycardia V-tach could occur
What is PAC? Tx?
P-wave is peaked
Less common, but the same parameters as PCV
<6 PAC is normal
Initiates SVT
Tx is same as PVC
What is Junctional? Tx?
If it has symptoms then pace!
No p-waves
Regular rhythm
What are causes of reversible asystole (H & T)
Hypovolemia
Hypoxia
Hydrogen ion
Hyper/hypokalemia
Hyperthermia
Tension pneumothorax
Toxins
Thrombosis pulmonary
Tamponade cardiac
Thrombosis coronary
What is accelerated idioventricular rhythm? Tx?
Causes: open heart surgery, drug toxicity (digoxin, cocaine)
S/S: wide QRS
Tx: usually will self-correct, treat the underlying cause
What is asystole? Tx?
flat line
CPR and Epi
What is PEA? Tx?
No pulse, but has an electrical signal
Risk Factors: cardiac tamponade, blunt force trauma
Tx: Epi, compressions, tx underlying conditions
