Fluids Flashcards
Body weight %
60% of total body weight is water
40% is intracelluar (2/3)
20% is extraceullar (1/3)
how much fluid is lost daily through urine?
stool?
lungs/skin?
up to 1500 ml
up to 250 ml
up to 900 ml
roughly 2500 p/day
standard Na
K
Cl
HCO3
135-150
3.5-5.0
98-106
22-30
standard maintenance fluid volumes
4-2-1 p/hr
4 ml/kg/hr for first 10 kg
2 ml/kg/hr for second 10 kg
1 ml/kg/hr for remainder
examples of hypotonic solutions
1/2 normal saline
D5W
examples of isotonic solutions
normal saline
LR
examples of hypertonic solutions
NS + HCO3
3% saline
gold standard for surgical resusitation
LR
for fluid loss, how much should you give back?
determine the deficit, replace 1/2 over first 8 hours then then remainder over next 16 hours
what are the main cations and anions extracellularly?
Na+, Cl-
what are the main cations and anions intracellularly?
K+, phosphate-
what determines the osmolality of ECF?
Na
hypo/hypernatremia can cause…
coma, muscle weakness
hyponatremia is usually dilutional needs to be corrected slowly (<0.5 mEqhr)
Caution for Central Pontine Myelinolysis if given too quickly
hypernatremia needs to be corrected slowly (<0.7 mEqhr)
caution for cerebral edema
signs of hypokalemia
Muscle fatigue, Paralysis, Cardiac Arrhythmia
Rhabdomyolysis, EKG Changes (ST depressions)
signs of hyperkalemia
Cardiac Changes (peaked T waves), Flaccid Paralysis dialysis
magnesium behaves like…
K
pH of tissues is regulated by…
chemical buffers
respiratory compensation
renal compensation
Respiratory Acidosis
Respiratory Alkalosis
Metabolic Acidosis
Metabolic Alkalosis
(pCO2 > 45 mm Hg)
(pCO2 > 45 mm Hg)
(HCO3- < 23 me/l)
(HCO3- > 26 me/l)
shock
Acute circulatory failure with inadequate or inappropriately distributed tissue perfusion resulting in generalized cellular hypoxia
class II shock
tachycardia begins (>100bpm), normal BP
class III shock
BP drops
