Which condition is a cause of distributive shock?

• A. Anaphylaxis
• B. Cardiac tamponade
• C. Hypovolemia
• D. Pulmonary edema

Answer: (A)

Distributive shock is driven by widespread vasodilation and leaky vessels, which causes low blood pressure and poor tissue perfusion even if the overall blood volume is adequate. Anaphylaxis fits this mechanism because it triggers a massive release of mediators that dilate blood vessels and increase capillary permeability, leading to systemic hypotension and decreased perfusion.

The other conditions produce shock through different pathways: cardiac tamponade creates obstructive shock by compressing the heart and reducing preload; hypovolemia causes hypovolemic shock from loss of circulating volume; pulmonary edema is typically associated with cardiogenic or volume overload states, not the widespread vasodilation seen in distributive shock.