Cardiac Arrest and Chest Pain (Emerg flash cards)
What are the indications for electrical cardioversion?
“Paroxysmal SVT
Atrial fibrillation/Atrial flutter
Ventricular tachycardia”
What are the pre-medication options before electrical cardioversion?
“Midazolam 1-5mg (+/- fentanyl 50-200mcg)
Propofol 50-150mg IV
Ketamine 0.25-1.5mg/kg IV
Etomidate 20mg IV”
What is synchronized cardioversion?
Delivery of a low-energy shock that is timed with the patient’s cardiac cycle (synchronized with the peak of the QRS complex)
What is unsynchronized cardioversion?
Delivery of a high-energy shock, with no time delay (delivered as soon as button is pressed on defibrillator)
What can happen if a low-energy shock is delivered at the wrong point in the cycle?
If the shock occurs on the t-wave (during repolarization), there is a high likelihood that the shock can precipitate VF (Ventricular Fibrillation)
What are the indications for synchronized cardioversion?
“unstable atrial fibrillation
atrial flutter
atrial tachycardia
supraventricular tachycardias”
When is unsynchronized cardioversion used?
- there is no coordinated intrinsic electrical activity in the heart (pulseless VT/VF), or
- the defibrillator fails to synchronize in an unstable patient
What “dose” of electricity is given in synchronized cardioversion?
pSVT/Aflutter: 150J biphasic or 300J monophasic
Vtach/Afib: 200J biphasic or 360J monophasic
What is the management of stable atrial fibrillation or flutter?
If HR > 120: rate control
Then consider rhythm control
What are the medical management options for acute narrow complex afib with HR >120?
"Diltiazem 20mg IV Verapamil 2.5-4mg IV Metoprolol 5mg IV Amiodarone 150mg over 10min Digoxin 0.5mg IV"
What are the medical management options for acute wide complex afib with HR >120?
“Procainamide 30mg/min to 17mg/kg
Amiodarone 150mg over 10min”
What is the general initial management of Vfib or pulseless vtach?
“Intubate, ventilate, early IV/IO access (med admin)
Treat reversible causes”
Name 7 reversible causes of Vfib/Vtach
"Hypovolemia Hypoxia Acidosis Hyper/o kalemia Hypothermia Toxins Ischemia"
Should you start CPR or shock first?
Shock first if defibrillator is immediately available; if not start CPR and interrupt for defibrillator
Describe key features of high-quality CPR
5cm compression, 100-120/min, with complete chest recoil. Change compressors q2min.
Minimize interruptions, avoid ventilation >10/min, monitor end-tidal CO2
For what ECG findings do you initiate CPR?
VFib and pulseless VTach
What are the two preferred medications that can be provided during CPR?
Epinephrine: 1mg IV q3-5min
Amiodarone: 300mg IV bolus, can add 150mg IV (2nd dose)
What alternate medications can be provided during CPR?
“Refractory VFib: lidocaine, 1.5mg/kg IV, q3-5min (max 3mg/kg)
Polymorphic VTach: Magnesium sulfate, 2g IV”
What “dose” of electricity is given for vfib or pulseless vtach?
200J biphasic or 360J monophasic
What “dose” of electricity is given for unstable afib?
200J biphasic or 360J monophasic
For wide-complex tachycardia, when should you consider synchronized cardioversion?
Early: meds only revert VT 30% of the time
What medications can be used for wide-complex tachycardia?
“Procainamide 30mg/min (max 17mg/kg)
Amiodarone 150mg over 10min (repeat x2 PRN)”
What is the next step after one antidysrhythmic fails?
Electric cardioversion: multiple antidysrhythmics can have proarrythmogenic effects
What is the first step for a stable patient in paroxysmal supraventricular tachycardia (pSVT)?
Vagal manoeuvres
