Operating Room Emergencies

Allergic reactions can occur anytime a patient is exposed to a drug. Histamine release can cause vasodilation and hypotension. True anaphylaxis involves IgE antibodies. Epinephrine acts to destabilize mast cells, affecting their ability to degranulate. Vasopressin is useful in treating the hypotension associated with anaphylaxis if the patient is unresponsive to epinephrine.