Q: 68 year old male with previous history of hypertension controlled at home with Lopressor - admitted to ICU with community acquired pneumonia. While receiving first dose of intravenous antibiotics, patient became flushed and hypotensive. Anaphylaxis from antibiotic is suspected. "Epi" is administrated. Patient's response to epinephrine seems not optimum. Knowing patient was on chronic beta-blocker therapy at home, you decided to administer Glucagon. Which caution should be exercise?


Answer: Avoiding quick IV push

Patients on chronic beta-blocker therapy are likely to be resistant to epinephrine. Glucagon has an unique property of been inotropic and chronotropic effects that are not mediated through beta-receptors. Quick IV push, which are common to practice in such situations, should be avoided as rapid administration can induce vomiting and aspiration pneumonia. It should administered slowly over five minutes.



Reference: 

Thomas M, Crawford I. Best evidence topic report. Glucagon infusion in refractory anaphylactic shock in patients on beta-blockers. Emerg Med J 2005; 22:272.