In treating bradycardia, if atropine fails, which medications may be used next?

When treating bradycardia, if atropine is ineffective, the next line of management typically involves the use of medications that can increase heart rate and improve cardiac output. Dopamine and epinephrine are both adrenergic agonists that can stimulate the heart and raise the heart rate.

Dopamine functions by activating beta-adrenergic receptors, which can increase heart contractility and heart rate, particularly at higher doses. Epinephrine also acts on both alpha and beta receptors, enhancing myocardial contractility and increasing heart rate and vascular resistance, making it a versatile option for acute management scenarios, including bradycardia that does not respond to atropine.

Using these agents allows for a more immediate and effective response in stabilizing the patient, particularly in emergency situations where bradycardia can lead to hemodynamic instability. This physiological action is critical when addressing symptomatic bradycardia, where rapid heart rate modification is necessary.