Dysrhythmias Flashcards
stable or unstable
- Interpretation based on a spectrum
- ALOC, ↓BP, CP, pulmonary edema
-This is not a dichotomous decision. If someone is able to talk to you, they are perfusing enough to get o2 to the brain – they are STABLE even if their BP is 80
regular or irregular rhythm?
- Irregular
- Above the ventricles
- NOT VT
- Block AV Node
are P-waves present?
If there are P waves present, it is unlikely that it is a tachydysrythmia
Narrow or wide complex?
Narrow
- Above the ventricles
- Block the AV- Node
- Not VT
- Duration (<0.12 (adults), < 0.08 (children))
- If it is narrow, its from the atrium. If its wide its from the ventricles
- If you have narrow complex you need to block the av node
Group A: narrow, regular, no p-waves
- PSVT
- Atrial Flutter
- WPW (orthodromic)
- Narrow complex VT (very rare)
-Cause: electrical circuit movement
- Narrow complex VT resolves by shock etc. its not picked up very often
- Orthodromic – narrow – starts in atrium
- Antidromic – wide – starts in ventricle
- WPW – accessory pathway
- The AV node cannot go faster than 220! If it goes higher than that, there is an accessory pathway
- A flutter = microcircuit issue
Treatment for group A dysrhythmias
STABLE
- Vagal maneuvers
- AV Nodal blockers: Adenosine, CCB, ẞ-Blocker
- Cardioversion
UNSTABLE
- Can consider Adenosine but…
- Cardioversion start at 50J and 2x every time
- You need to block the AV node
- If you use medication and it doesn’t work, you use synchronized cardioversion
- Unstable: you CAN push adenosine
- What does adenosine feel like? FEELS LIKE DYING!! You need to prime the patients so theyre ready for this
Group B dysrhythmias: narrow, irregular, no Ps
- A-fib
- A-Flutter with variable block
-Cause: increased automaticity
- Anyone in group A (SVT, Aflutter) – AV NODE ISSUE
- Adenosine is FAST! Lasts for a few seconds and goes away – if you give adenosine to someone with aflutter, it will NOT CURE Aflutter
- For Aflutter, you need a longer acting agent
-Increased automaticity – fireworks going off in the atrium all the time
Group B treatment
- it depends:
- chronic: rate control
- new onset: rhythm control
You will see a chronic pt if they have palpitations
Group B treatment: Chronic - stable vs unstable
Stable patient
- Stabilize Atrium by blocking AV node
- CCB
- ẞ-blocker
- Digoxin…old drug
- Diltiazem 5-10mg IVP slow. If tolerated can 2x it. (Up to 60mg in 30min)
Unstable
- Rapid Cardioversion: Start high! Sync!
- Support Blood Pressure: Pressers – you need to ensure perfusion of brain and heart – success rate of conversion with low blood pressure is LOW
- If the diastolic pressure is low, you will NOT convert these patients because their heart is irritable! You need to get the BP up!
- Slow down heart: drips not IV Push
- If you push, you may bottom out the BP and cause cardiac arrest
- But, if the person is bigger, you may need to push since the drip wont do anything
- Magnesium – vasodilator
- Repeat Cardioversion
- Other considerations: Is it really A-Fib?
-For elderly, TREAT UNDERLYING CAUSE FIRST!
Group B tx: new onset
- Rhythm Conversion: Ottawa Aggressive Protocol for A-fib
- Clear Hx with in 48 hours
- No structural heart dz
- Age not a contraindication
- Caveat in elderly don’t rush often p/w vague sx’s
- New onset – you want to get them back into sinus rhythm
- AGE IS NOT A DETERMINING FACTOR!
- If you have a patient with longstanding Afib, the risk of converting them is STROKE!
-Chemical cardioversion: Procainamide 1g over 1 hour ↓ -Electrical cardioversion: Biphasic 200J ↓ -D/C home without meds
Group C: wide, regular, no Ps
- VT
- SVT with aberrancy (BBB)
- Antidromic WPW
- Cause: circuit re-entry in the ventricles
- WIDE and REGULAR – VTACH!!!!!!
- WPW – shortened PR interval with delta wave
- You CARDIOVERT for unstable people!!
Group C tx: stable vs unstable
STABLE
- Consider Adenosine
- Cardioversion: 100J
- Antiarrythmic Infusion: Procainamide, Amiodarone, Magnesium
UNSTABLE
- CARDIOVERT
- ACLS
-Why consider adenosine? SVT with abberancy - adenosine in this patient that is stable is like pressing a restart button on the heart
AV node
- AV node cant go faster than 200-220! This is 300 so its WPW
- CALL CARDIOLOGY!! In the ED, think about in this group whether they are stable or unstable. If you convert, do they go home or get admitted? ADMITTED
- Vtach can turn to Vfib!!
Group D: wide, irregular, no Ps
- A-fib with BBB
- A-fib with WPW
- A-flutter with variable block and BBB
- Polymophic VT = Torsades
treatment of group D dysrhythmias
STABLE
- A-Fib = Rate control: Be carful If…
- WPW
- Regular: Consider *Adenosine (some people don’t like this because it can send them into overdrive), electricity
- Irregular: No AV nodal blocker, Electricity, Procainamide
- Torsades = Magnesium
UNSTABLE
- Defibrillate
- ACLS
- Orthrodromic- Narrow
- Antidromic – Wide treat as VT Cardioversion
- A-Fib with WPW- very hard, if in doubt reg or irreg okay to cardiovert 120-200J Biphasic and 200J, meds likely started in the Unit
- WHEN ITS IRREGULAR YOU DEFIBRILLATE
