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+--- Thread: Question 1 - redceo123 (/showthread.php?tid=808532)
Question 1 - redceo123 - ArchivalUser - 06-03-2015
A 35-year-old man is referred to the renal clinic for evaluation of proteinuria. He has no complaints other than foamy urine. The following data are obtained from the patient:
Inulin clearance 100 mL/min
Plasma osmolarity 286 mOsm/L
Plasma sodium concentreation 140 mEq/L
Urine flow 1.44 l/ 24 hour
Urine osmolarity 205 mOsm/L
Urine sodium concentration 100 mEq/L
How much sodium does this patient reabsorb each day?
A. 14 mEq
B. 144 mEq
C. 244 mEq
D. 20,016 mEq
E. 20,160 mEq
Show your calculation. thanks
0 - ArchivalUser - 06-03-2015
Of the Na filtered, 99-99.5% is norm reabsorbed ( 67% PCT, 25% Loop hen & 8% DCT)
^Na filtration: ( Plasma Na conc & GFR = inulin clearance)
140 mEq/L x 100 mL/min -> 20,160 mEq/ DAY
^^Na excreted: ( Urine Na conc & Urine flow)
100 mEq/L x 1.44 L / day - > 144 mEq/DAY
Na reabsorption = ^Filtered – ^^Excreted -> 20,160 mEq/DAY - 144 mEq/DAY -> 20,016mEq.
The End.
0 - ArchivalUser - 06-03-2015
ohhh per "Day".....thats where i went wrong....thanks for the rescue as always!!!
0 - ArchivalUser - 06-03-2015
thanks cardio