When a person experiences arrhythmia (ie, cessation of effective heart contractions), he or she can lose a pulse and become unconscious. Urgent medical care then is needed to improve outcomes and prevent sudden cardiac death. This care should include an electrocardiogram to identify the underlying arrhythmia and guide treatment. It is important for healthcare professionals to understand the role of medications in the treatment of potentially fatal arrhythmias. They should be familiar with the treatment algorithms for cardiac emergencies (as published by the American Heart Association) such as ventricular fibrillation, pulseless ventricular tachycardia, pulseless electrical activity, asystole, and severe bradycardia. A quick response with appropriate medical care will increase a patient's chance of survival.