Why does severe angioedema, characterized by rapid swelling, potentially cause airway obstruction during anaphylaxis?

💡 Explanation

Histamine release from mast cells during anaphylaxis causes increased vascular permeability within the laryngeal mucosa, because this mechanism results in fluid extravasation and rapid tissue swelling. Therefore, airway obstruction occurs, rather than vasodilation caused by the complement cascade or direct bronchodilation by epinephrine.

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