If a patient's mean arterial pressure remains dangerously low despite normal cardiac output, which vascular mechanism is most likely at fault?

💡 Explanation

Widespread vasodilation causes a significant drop in total peripheral resistance (TPR). Because mean arterial pressure is the product of cardiac output and TPR, vasodilation drops the blood pressure; therefore, widespread vasodilation is the most likely culprit, rather than increased blood viscosity or problems with cardiac output itself.

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