Bradycardia in a Patient with Anaphylactic Shock Case Report

Anaphylactic shock, as a kind of distributive shock, is considered as a consequence of histamine induced vasodilatation with increased vascular permeability. Tachycardia is the early warning sign of shock and bradycardia is a rare manifestation of shock. A 78 year-old woman presented with shrimpinduced anaphylactic shock with bradycardia. She was treated by beta-blocker currently and further Thalium-201 myocardial scan showed reversible myocardial ischemia. She had full recovery after aggressive resuscitation and discharged without any sequelae. The causes of developing bradycardia in patients with anaphylactic shock maybe multifactorial involving hypotension or histamine induced transient SA node ischemia, Benzoid-Jarish reflex, and concurrent beta-blocker usage. Prompt management with epinephrine, atropine, inotropic/vasopressor agents and intravenous fluid resuscitation is mandatory. Glucagon should be considered if there is a concern of concurrent beta-blocker intoxication. Bradycardia developed during shock status, particular in patients with severe allergic reaction, coronary artery disease and current beta-blocker usage worth particular attention. ( J Intern Med Taiwan 2005; 16: 91-94 )