Pulseless: see Adult pulseless arrest
Unstable: Hypotension, altered mental status, shock, ischemic chest discomfort, acute heart failure
Synchronized cardioversion 100-200J
Stable:
Medications
Procainamide (first-line drug of choice)
20-50mg/min until arrhythmia suppressed (max 17mg/kg or 1 gram); then, maintenance infusion of 1-4mg/min x 6hr
Alternative administration: 100 mg q5min at max rate of 25-50 mg/min
Stop if QRS duration increases >50% or hypotension
Avoid if prolonged QT or CHF
Favored over Amiodarone in PROCAMIO trial; termination of<unk>  in 67% of procainamide group vs 38% of amiodarone group, adverse cardiac events 9% vs 41%, respectively 
Amiodarone (agent of choice in setting of AMI or LV dysfunction)
150 mg over 10min (15 mg/min), followed by 1 mg/min drip over 6hrs (360 mg total)
Then 0.5 mg/min drip over next 18 hrs (540 mg total)
Oral dosage after IV infusion is 400 -800 mg PO daily
Consider adenosine
Consider for diagnosis and treatment, if rhythm is regular and monomorphic (see rhythm diagnosis in regular<unk> 
6 mg IV as a rapid IV push followed by a 20 mL saline flush; repeat if required as 12 mg IV push
Synchronized Cardioversion (100J)
Synchronized cardioversion 100-200J
Procainamide (first-line drug of choice)
20-50mg/min until arrhythmia suppressed (max 17mg/kg or 1 gram); then, maintenance infusion of 1-4mg/min x 6hr
Alternative administration: 100 mg q5min at max rate of 25-50 mg/min
Stop if QRS duration increases >50% or hypotension
Avoid if prolonged QT or CHF
Favored over Amiodarone in PROCAMIO trial; termination of<unk>  in 67% of procainamide group vs 38% of amiodarone group, adverse cardiac events 9% vs 41%, respectively 
Amiodarone (agent of choice in setting of AMI or LV dysfunction)
150 mg over 10min (15 mg/min), followed by 1 mg/min drip over 6hrs (360 mg total)
Then 0.5 mg/min drip over next 18 hrs (540 mg total)
Oral dosage after IV infusion is 400 -800 mg PO daily
Consider adenosine
Consider for diagnosis and treatment, if rhythm is regular and monomorphic (see rhythm diagnosis in regular<unk> 
6 mg IV as a rapid IV push followed by a 20 mL saline flush; repeat if required as 12 mg IV push
20-50mg/min until arrhythmia suppressed (max 17mg/kg or 1 gram); then, maintenance infusion of 1-4mg/min x 6hr
Alternative administration: 100 mg q5min at max rate of 25-50 mg/min
Stop if QRS duration increases >50% or hypotension
Avoid if prolonged QT or CHF
Favored over Amiodarone in PROCAMIO trial; termination of<unk>  in 67% of procainamide group vs 38% of amiodarone group, adverse cardiac events 9% vs 41%, respectively 
Alternative administration: 100 mg q5min at max rate of 25-50 mg/min
150 mg over 10min (15 mg/min), followed by 1 mg/min drip over 6hrs (360 mg total)
Then 0.5 mg/min drip over next 18 hrs (540 mg total)
Oral dosage after IV infusion is 400 -800 mg PO daily
Consider for diagnosis and treatment, if rhythm is regular and monomorphic (see rhythm diagnosis in regular<unk> 
6 mg IV as a rapid IV push followed by a 20 mL saline flush; repeat if required as 12 mg IV push
Unstable: Hypotension, altered mental status, shock, ischemic chest discomfort, acute heart failure
Unsynchronized cardioversion (defibrillation) 200J
Stable:
A fib with preexcitation
1st line - Electric Cardioversion
2nd line - Procainamide, amiodarone, or sotalol
A fib with aberrancy
Polymorphic V-Tach / Torsades De Pointes
Give IV MgSO4
Emergent defibrillation (NOT synchronized)
Correct electrolyte abnormalities (esp hypoK, hypoMg)
Stop prolonged QT meds
Unsynchronized cardioversion (defibrillation) 200J
1st line - Electric Cardioversion
2nd line - Procainamide, amiodarone, or sotalol
Give IV MgSO4
Emergent defibrillation (NOT synchronized)
Correct electrolyte abnormalities (esp hypoK, hypoMg)
Stop prolonged QT meds
≥3 episodes within 24 hours considered electrical storm and may require alternate treatment (i.e. beta blockade, sedation, ablation)
True Vtach generally has rate >120bpm. If rate <120bpm or refractory to other therapy, consider other causes
When in doubt, use cardioversion for treatment of regular WCT. In irregular WCT, consider Afib with WPW in which Procainamide is the treatment of choice
In very<unk>  complex (>0.2 msec) and <120 bpm in a patient with significant history, consider giving calcium chloride to treat hyperkalemia
Consider Acidosis
Sodium channel blockade (e.g. from benadryl, TCA, or cocaine toxicity) may cause very<unk>  complex (>0.2msec)<unk>  with rate <120bpm
Treat with sodium bicarbonate
Lidocaine, Procainamide, Amiodarone all block Na channels and may result in asystole in patients with intrinsic or extrinsic Na-channel blockade
Treat with sodium bicarbonate
Lidocaine, Procainamide, Amiodarone all block Na channels and may result in asystole in patients with intrinsic or extrinsic Na-channel blockade
Wide-complex tachycardia
Regular
Narrow-complex tachycardia
AV Node Independent
Junctional tachycardia
Sinus tachycardia
Third degree AV block
Atrial tachycardia 