FREE WATER CLEARANCE
by Stephen Z. Fadem, M.D., FACP, FASN
C
H
2
0
= V - V X (U
osm
/P
osm
)
URINE OSMOLALITY
PLASMA OSMOLALITY
V
ml/min
OSMOLAR CLEARANCE (C
OSM
) =
FREE WATER CLEARANCE =
INTERPRETATION =