In renal physiology, renal blood flow (RBF) is the volume of blood delivered to the kidneys per unit time. In humans, the kidneys together receive roughly 20 - 25% of cardiac output, amounting to 1.2 - 1.3 L/min in a healthy adult.[1] It passes about 94% to the cortex. RBF is closely related to renal plasma flow (RPF), which is the volume of blood plasma delivered to the kidneys per unit time.
| Sodium
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Inulin
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Creatinine
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PAH
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| SNa = 150 mEq/L
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SIn = 1 mg/mL
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SCr = 0.01 mg/mL
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SPAH =
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| UNa = 710 mEq/L
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UIn = 150 mg/mL
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UCr = 1.25 mg/mL
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UPAH =
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| CNa = 5 mL/min
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CIn = 150 mL/min
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CCr = 125 mL/min
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CPAH = 420 mL/min
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|
|
|
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ER = 90%
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|
|
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ERPF = 540 mL/min
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While the terms generally apply to arterial blood delivered to the kidneys, both RBF and RPF can be used to quantify the volume of venous blood exiting the kidneys per unit time. In this context, the terms are commonly given subscripts to refer to arterial or venous blood or plasma flow, as in RBFa, RBFv, RPFa, and RPFv. Physiologically, however, the differences in these values are negligible so that arterial flow and venous flow are often assumed equal.