Cardiovascular drugs are a common cause of poisoning, and toxic bradycardias can be refractory to standard ACLS protocols. It is important to consider appropriate antidotes and adjunctive therapies in the care of the poisoned patient in order to maximize outcomes. While rigorous studies are lacking in regards to treatment of toxic bradycardias, there are small studies and case reports to help guide clinicians’ choices in caring for the poisoned patient. Antidotes, pressor support, and extracorporeal therapy are some of the treatment options for the care of these patients. It is important to make informed therapeutic decisions with an understanding of the available evidence, and consultation with a toxicologist and/or regional Poison Control Center should be considered early in the course of treatment. 1. Background Nearly 2000 poisoned patients are seen per day in Emergency Departments across the United States, and unintentional poisoning is a significant cause of mortality even surpassing motor vehicle accidents as a cause of death in people aged 35–54 [1]. Cardiovascular drugs rank second only behind analgesics as the leading cause of fatality in poisoned patients. Polypharmacy, intentional or unintentional ingestions, and toxic exposures should be entertained in the differential diagnosis of the bradycardic critically ill patient. Consideration and recognition of poisoning may shed light onto altered physiologic responses that may be refractory to traditional therapies. Standard resuscitation algorithms are often insufficient, and it is important to consider appropriate antidotes and adjunctive therapies when caring for the poisoned patient. Additionally, consultation with a toxicologist or poison control center is recommended to assist in caring for the poisoned patient. Toxic bradycardias are often refractory to standard ACLS protocols due to toxin effects on cardiac and vascular receptors and cellular physiology. Recognition of a toxic etiology for compromised circulation in the setting of bradycardia is crucial in tailoring appropriate therapy. Beta blockers, calcium channel blockers, and cardiac glycosides (digoxin) represent the classes of medication most described in association with fatality due to drug exposure according to the American Association of Poison Control Centers. This discussion will also briefly cover clonidine and acetylcholinesterase inhibitors, such as organophosphates and carbamates, because both have therapeutic consideration outside of standard supportive care. This paper discusses common treatment considerations that
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