Flashcards in C16 Electrolytes Deck (19):
inside cells- 2/3 of body water
outside cells- 1/3 of body water
# if osmoles/liter solvent, way of measuring total substances in a solution
# of osmoles/kg solvent
1 mole of dissolved substance
2 osmolality test methodologies?
freezing point depression & vapor pressure
2 Na + (BUN/3) + (Glucose/20)
difference between the (measured) osmolality & the (calculated) osmolality
What do you suspect in an increased osmolar gap?
an additonal abnormal substance: ethanol, methanol, ethylene glycol (antifreeze)
Plasma sodium accounts for what percentage of plasma osmolality?
What can cause diabetes insipidus?
ADH deficiency, without water re-absorption, 10-20 liters of urine per day
increased osmolality are concerns for:
infants, unconsious pts, & elderly
Water concentration is regulated by?
thirst & urine output
Thirst & urine production are regulated by?
increased osmolality stimulates:
hypothalamus to stimulate the sensation of thirst, posterior pituitary secretes ADH, & ADH increases H2O absorption by renal collection ducts
regulates blood volume via plasma sodium
decreased bp stimulates ___ secretion by the renal glomeruli
Aldosterone has 2 effects on blood volume/pressure:
stimulates reabsorption of sodium by the kidneys, water passively follows sodium, increasing blood volume, aldosterone stimulates vasoconstriction- increasing bp