Fluid and Electrolyte Imbalance
Lee, Chin-Chan
Chang Gung Memorial Hospital, Keelung
1
Outline
Salt and Water Control
Hyponatremia
Hypernatremia
Case Demonstration
60%
20%
15%
40%
5%
60%
20%
15%
40%
5%
60% (TBW)
40% (ECF)
20% (ICF)
15%
5%
Not really correct, but
useful
Urine osmolality
Na, Cl, Urea, Glu,..
ADH
ADH secretion
Urine sodium
Volume status
Renin-angiotensin-aldosterone
Low UNa means low effective
Low effective circulating volume
circulating volume
High plasma osmolality
Take Home
Message
Osmoregulation and volume
regulation
Definition of Hyponatremia
Importance of Sodium level and
Osmolality
(both Urine and Blood )
Take Home
Message
Hyponatremia always accompanied with high Uosm
(except..), that means High ADH
Causes of persistent High ADH, e.g. Low effective
circulating volume (the UNa will be low)
If no evident causes found, then, SIADH possibility
high, (the UNa will be high)
Some exception: renal failure….
(both Urine and Blood )
Thank You
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