Effective renal plasma flow
Effective renal plasma flow (eRPF) is a measure used in renal physiology to calculate renal plasma flow (RPF) and hence estimate renal function. The eRPF can be calculated with where extraction ratio is the ratio of compound entering the kidney that is excreted into the final urine. When using a compound with an extraction ratio near 1, such as para-aminohippurate (PAH), eRPF approximates RPF. Therefore, PAH clearance can be used to estimate RPF.