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+--- Thread: physio q.... - rawalian (/showthread.php?tid=580397)
physio q.... - rawalian - ArchivalUser - 04-16-2011
A 70-kg (154-lb) man on a fixed NaCl intake
(200 mmol/day) is given daily injections of a
potent mineralocorticoid hormone for 4 days. He
has free access to water and consumes his usual
caloric intake. Excretion of NaCl is as follows:
Day NaCl (mmol)
1 30
2 90
3 180
4 200
Assuming that 1 L of 0.9% saline contains 150
mmol of NaCl and weighs 1 kg, how much will
this patient weigh (in kg) at the end of day 4?
(A) 66
(B) 68
© 70
(D) 72
(E) 74
0 - ArchivalUser - 04-16-2011
is it "D"
0 - ArchivalUser - 04-16-2011
E..
0 - ArchivalUser - 04-16-2011
sarim or maryam can you guys PLEASE explain how you got the answer...thanx...
0 - ArchivalUser - 04-16-2011
answer is D though...
0 - ArchivalUser - 04-16-2011
the man was given 800 mmol of NaCl in 4 days (200 mmol/day)
out of 800, he lost 500 in the urine (30 + 90 + 180 + 200 =500)
so at the end of 4th day he's got 300 mmol NaCl in excess compared to initial state
150 mmol = 1 kg
300 mmol = 2 kg
Initial wt 70 kg + 2 kg (from excess 300 NaCl) =72 kg
0 - ArchivalUser - 04-16-2011
THANx a lot that was helpful..
GL