Why are units of GFR in milliliters per minute per 1.73 m2?
The clearance of substances is computed in units of milliliters/minutes.
However, because kidney size (and therefore amount that can be cleared) varies by a person’s body size, to determine whether a person has normal GFR, the clearance in units of mL/min is then adjusted for normal body surface area (BSA) by multiplying by 1.73 and dividing by the individual’s BSA.
Accurately estimating the glomerular filtration rate (GFR) is unfortunately not an easy task.
Multiple methods for doing this have been developed over the past few decades and each newly adopted method, although better than its predecessor, has been far from perfect.
