Renal Part 2: Schoenwald Flashcards
Electrolyte Panel: (includes)
Na K CL CO2
Kidney is the main regulator of water and _____
sodium
Sodium: normal range
Normal 136-145 mEq/L
Sodium is the primary circulating _____
cation (extracellular space)
Sodium is needed for?
neuromuscular function
Sodium: -how are serum levels balanced?
Serum levels are the balance between dietary intake and renal excretion
Sodium: -indicator of ____
*free body water -If free water increased, Na diluted and levels decrease -If free water decreased, Na concentrated and levels increased
Sodium is a major contributor to _____
plasma osmolality
Osmolality: normal serum
280-295 mOsm/kg H20
Osmolality is useful in which settings?
hyponatremia, evaluating ADH (antidiuertic hormone) related illnesses
Osmolality: -measures?
concentration of dissolved particles in blood
As amount of free water increases, amount of particles decreases= osmolality ______
osmolality decreases
As amount of free water decreases, amount of particles increases=osmolality
increases
Therefore, osmolality decreases with _____
overhydration, and increases with dehydration
Antidiuretic Hormone(ADH): -regulates?
body water and osmolality
ADH is stimulated by (3 things)
Increased osmolality Hypovolemia Thirst
ADH acts on the ______ ______ to increase permeability=increase water reabsorption=more concentrated urine
collecting tubule
Osmolality-Serum: -Is increased in:
-Hypernatremia -Hyperglycemia -Ketosis -Dehydration -Diabetes insipidus
Osmolality-Serum: -is decreased in:
-Overhydration -Syndrome of inappropriate ADH
Syndrome of inappropriate ADH=
=Abnormally high amount of ADH present –Increased water reabsorption leading to decreased serum sodium levels —Lose sodium in urine
Syndrome of inappropriate ADH: -What is a common cause of this syndrome?
drugs (commonly after anesthesia type drugs ie post surgery)
Diabetes insipidus= inadequate amount of ____ present
ADH
Diabetes Insipidus: -Sx? -Labs?
Sx: increased thirst and passage of large volumes of dilute urine -Hypernatremia present
Urine Osmolality: normal range
50-1200 mOsm/kg H20
Urine Osmolality: -measures? -Is more accurate than?
-Measures dissolved particles in urine -More accurate than specific gravity
T/F: Urine Osmolality Evaluates ability of kidney to concentrate urine
True
Urine Osmolality: -Is Increased in which conditions?
-SIADH -CHF
Urine Osmolality: -Is decreased in which conditions?
-Diabetes insipidus -Excess fluid intake
Hyponatremia is defined as:
Serum sodium <136mEq/L
Hyponatremia: 2 types
-Sodium depletion-free water loss -Dilutional-water intake greater than water output-(renal failure)
Hyponatremia: -most asymptomatic until ____
level<120 mEq/L
Hyponatremia: Sx?
-lethargy, nausea, mm cramps -**Cerebral edema (this can be lethal!!)
Hypernatremia is defined as
>145 mEq/L
Hypernatremia: -etiology
-Impaired thirst mechanism (ie stroke) or water loss without sodium loss (ie burns, or high fever) -dehydration
Which is more lethal, hyper or hyponatremia?
hyponatremia
Urine Sodium: -tests? -normal range?
-Spot testing or 24 hour urine –Normal values vary -Spot normal generally >20mEq/L