Arrhythmias in children.

Arrhythmias in children can be classified according to their effect on central pulse: Fast pulse rate - tachyarrhythmia; Slow pulse rate - bradyarrhythmia; and Absent pulse is pulseless arrest (cardiac arrest). Tachyarrythmia may be narrow complex tachycardia (QRS duration ≤ 0.08 s): sinus tachycardia (ST), supraventricular tachycardia (SVT), atrial flutter or Wide-complex tachycardia (QRS duration >0.08 s): ventricular tachycardia (VT), SVT with aberrant intraventricular conduction. The choice of therapy depends on the patient's degree of hemodynamic instability. Attempt vagal stimulation, if patient is stable and if it does not unduly delay chemical or electrical cardioversion. Bradyarrhythmias include: sinus bradycardia, sinus node arrest with atrial, junctional and idioventricular escape rhythms and AV block. The emergency treatment of bradycardia depends on its hemodynamic consequences. If heart rate is <60 beats per minute with poor perfusion despite effective ventilation with oxygen, it may be treated with chest compressions, epinephrine through IV or endotracheal tube. If bradycardia persists or responds only transiently, consider a continuous infusion of epinephrine or isoproterenol and plan for emergency transcutaneous pacing. If bradycardia is due to vagal stimulation or primary A-V block, giving atropine may be beneficial.