A 22-year-old man comes to the emergency department because of the onset of facial swelling, difficulty breathing 20 minutes after eating some trail mix. He has never had a similar episode before. Blood pressure is 80/40 mm Hg, pulse is 130/min, and respirations are 32/min. Examination shows generalized hives, swelling of his tongue and lips, and labored breathing with intercostal retractions. Which of the following hemodynamic changes are most likely present in this patient?

Question

Quizplus · Accepted Answer

Eductional Objective: Anaphylaxis can cause distributive shock due to widespread release of inflammatory mediators (eg, histamine) that leads to massive peripheral vasodilation.  Arteriolar vasodilation decreases systemic vascular resistance to cause hypotension, and venular vasodilation decreases central venous pressure and pulmonary capillary wedge pressure.  Cardiac output is often increased in early distributive shock due to reduced SVR and a baroreceptor reflex-mediated increase in heart rate

A 22-Year-Old Man Comes to the Emergency Department Because of the Onset