Regarding Arrhythmias

ACLS providers should be able to recognize the variety of dyrhythmias as in the past with a substantial amount of alteration and emphasis on the recognition and management of tachycardias;

Classification of various tachycardias 

Narrow complex/supraventricular--Sinus tach, atrial fib, atrial flutter, atrial tach (ectopic, reentrant), multifocal atrial tachycardia, AV nodal reentry tachycardia, junctional tach, accessory pathway-medicated tachycardia (atrial tach, atrial fib/flutter, AV reentry tachycardia);

Wide complex --Ventricular tachycardia, ventricular fibrillation, SVT with aberration (BBB or intraventricular conduction delay);

If a tachycardia results in pulselessness, shock, or congestive heart failure it should be presumed to be VT until 12-lead (and possibly an esophageal lead) are obtained;

Initial care providers are wrong more than 50% of the time in determining whether a wide complex tachycardia is ventricular vs. supraventricular;

In the past, lidocaine and adenosine have been given diagnostically to discriminate between SVT and VT of wide complex configurations. It is not effective and is inappropriate to do this.

Regarding Pharmacology

Peripheral IV drugs require 1-2 minutes to reach central circulation during cardiac arrest, continue to follow them with a 20 ml bolus of fluid and elevate the extremity 10-20 seconds; endotracheal drug administration (at 2-2.5 times the IV dose) appears to be unchanged as an alternative (for epinephrine, lidocaine, and atropine)-dilute these in 10ml of normal saline.


Amiodarone-Class IIb-"helpful" for ventricular control of rapid atrial rhythms with severe LV impairment and digitalis has not worked; cardiac arrest with persisitent VT/VF after defibrillation and initial dose of epinephrine, hemodynamically stable VT, polymorphic VT, and wide complex/unknown origin, atrial tachycardia, ventricular rate in preexitation atrial arrythmias. It is Class IIa for AF and in conjunction with cardioversion for refractory PSVTs.

In non-arrest situations it is given as 150mg over 10 minutes followed by a 1mg/min infusion for six hours and then reduced to a 0.5mg/min infusion. Additional doses of 150mg can be given up to a total daily dose of 2 grams. (One study cited success with AF when amiodarone was administered at 125mg/hr for 24 hours (a total of 3 grams). In pulseless VT/VF it is 300mg diluted in 20-30ml and given rapid infusion; supplemental doses of 150mg may be given for recurrent VT/VF followed by a similar infusion schedule listed above (2 gram total).

Atropine-Class IIa for all but Mobitz type II and 3rd degree blocks with new wide QRS complexes. It is not indicated for the latter two. Dosing remains the same as in previous guideline-3 mg is vagolytic and should be reserved for cardiac arrest patients.

Beta blockers-Class I for non-Q wave AMI and unstable angina.

Atenolol, metoprolol, and propanolol effective at reducing occurrence of VF in fibrinolytic-ineliglible post MI patients. Esmolol is Class I for treating PSVT, AF or atrial flutter without preexcitation, and Class IIb for ectopic atrial tachycardia, symptomatic sinus tachycardia, myocardial ischemia and torsades de pointes (in conjunction with pacing).

Bretylium has been dropped from recommendations (despite remaining IIb) because of supply problems and "availability of safer agents" and its "high occurrence of side effects."

Calcium channel blockers-may assist in ventricular control in AF, atrial flutter and MAT. Dosing remains unchanged, diltiazem "seems to be equivalent in efficacy to verapamil." Diltiazem offers the advantage of producing less myocardial depression than verapamil."

Dopamine-role in bradycardia after pacing/atropine unchanged. May be effective in doses of 3-7.5 mcg/kg/min, though recommended for 5-20 mcg/kg/min

Isoproterenol-temporizing agent for torsades de pointes before pacing (Class Indeterminate) and Class IIb after pacing, atropine and dopamine in bradycardia. Same dosing (higher infusion rates are Class III).

Lidocaine-Class Indeterminate for VF/pulseless VT and control of hemodynamically challenging PVCs; Class IIb for stable VT. Dosing, if used in VF is 1.0-1.5mg/kg with repeat dose of half initial dose every 3-5 minutes (total of 3mg/kg/hr). Continued reminder that patients over 70 years old should receive half of the recommended repeat doses (half of half dose). Lidocaine is "acceptable" though "its efficacy is poor and methodologically weak;' it is now considered a "second tier" agent- "other drugs are preferred over lidocaine in each VT scenario. Procainamide and sotalol are more effective in VT".

Magnesium-no routine use; consider in hypomagnesic conditions and torsades de pointes. Emergent administration is "1-2 grams is diluted in 100ml given over 1-2minutes."

Procainamide-routinely given at 20 mg/min, in critical situations may be given up to 50 mg/min. End points remain the same. Is Class IIa in managing AF and atrial flutter, IIb for preexcitation atrial arrhythmias and wide complex tachycardias of unclear origin.

Sotalol-for use in supraventircular and ventricular arrhythmias; IV dose 1.0-1.5 mg/kg at 10 mg/min. Oral form only available in US currently.

Disopyramide, Flecainide, Ibutilide, propafenone- antiarrhythmics with unclear practicality and efficacy, particularly in compromised circulatory conditions.

Epinephrine-"there is a paucity of evidence to show that it improves outcome in humans." Concerns raised about creating "severe toxic hyperadrenergic" state, increased myocardial dysfunction, and correct dosing persist. Can be given via ET tube. High dose not recommended for routine use if 1mg doses are ineffective (Class Indeterminate. "Interpretation: acceptable but not recommended.") but also listed as Class IIb: "acceptable but not recommended; weak supporting evidence"). Dosing in cardiac arrest remains the same, with a reminder that an infusion can be set up to deliver the equivalent of 1 mg every 3-5 minutes (though set up appears wrong in Guidelines 2000 supplement pg I-130). Dosing for symptomatic bradycardia is the same (2-10mcg/min) but initial dose is 1mcg/min.

Vasopressin-directly stimulates smooth muscle receptors causing vasoconstriction. Can be used as an alternative to epinephrine in initial pharmacological management of VF "Class IIb: acceptable; fair supporting evidence"), may be beneficial for asystole and PEA 
but sufficient data is lacking (Class Indeterminate: not recommended; not forbidden); insufficient data also to recommend using vasopressin after using epinephrine. Dose, given once, is 40 units (same dose can be given intraosseously) with half-life (animal models) of 10-20 minutes.

Norepinephrine-no changes, still recommended for use with severe hypotension (systolic less than 70mmHg) and low peripheral resistance.

Dobutamine-recommended use remains unchanged ("severe systolic heart failure"). Dose range is 5-20 mcg/kg/min.

Amrinone/milrinone---inotropic and vasodilatory properties (similar to dobutamine) for use in heart failure and cardiogenic shock.

Calcium---remains Class III except for specific indications (Class IIb for hyperkalemia, hypocalcemia, calcium channel blocker toxicity).

Digitalis-effective, but other agents preferred for initial management of atrial fibrillation.

Nitroglycerin-no significant changes in indications or dosing.

Sodium nitroprusside-vasodilator for severe heart failure and hypertensive emergencies. In MI patients, nitroglycerin is preferred, with this agent used if nitroglycerin is ineffective.

Sodium bicarbonate-laboratory and clinical data do not support routine use. No changes in indication or dosage.