What happens to mean arterial pressure as arterial branches become smaller?

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What happens to mean arterial pressure as arterial branches become smaller?

As blood moves from large arteries into progressively smaller branches, the driving pressure falls. This happens because resistance rises dramatically as radius decreases (Poiseuille’s law: resistance ∝ 1/r^4), and there are many small vessels in series adding up to a large total resistance. The arterioles, in particular, are the main site of this resistance, so the mean arterial pressure drops downstream from the aorta. In a healthy system, arterial pressure is highest near the heart and decreases as vessels become smaller, especially across the arterioles and capillaries. So, mean arterial pressure decreases as arterial branches become smaller.

As blood moves from large arteries into progressively smaller branches, the driving pressure falls. This happens because resistance rises dramatically as radius decreases (Poiseuille’s law: resistance ∝ 1/r^4), and there are many small vessels in series adding up to a large total resistance. The arterioles, in particular, are the main site of this resistance, so the mean arterial pressure drops downstream from the aorta. In a healthy system, arterial pressure is highest near the heart and decreases as vessels become smaller, especially across the arterioles and capillaries. So, mean arterial pressure decreases as arterial branches become smaller.

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