Cross Species - Chemistry Electrolytes Flashcards
(59 cards)
what electrolytes are included on a biochemistry panel?
sodium, potassium, & chloride
what minerals are included on a biochemistry panel?
calcium, phosphorus, & magnesium
what is the predominant extracellular cation on a biochemistry panel? what is it tightly linked to?
sodium - extracellular fluid (hydration status!!)
what are the top causes of hypernatremia?
water loss in excess of sodium, so dogs/cats - gi fluid loss, adipsia - CNS disease & water deprivation, & excessive sodium ingestion seen in salt poisoning in calves
what are the top causes of hyponatremia?
hypotonic fluid loss - DKA, gi loss (severe diarrhea in horses & cattle, but especially horses), addison’s disease, & diuretic administration + volume overload/excessive water intake
why can’t you correct hyponatremia too quickly? what is the maximum rate?
CNS signs can occur with rapid correction - max rate, no greater than 0.5 mEq/L/h
what is the major intracellular cation? why is it tightly controlled?
potassium - very important for cellular function!!! plasma level is very low compared to sodium
what are the top causes of hyperkalemia?
spurious (thrombocytosis, hemolysis, EDTA coagulant), uroabdomen (foals, obstructive uropathy in dogs/cats), oliguric/anuric acute renal failure, addison’s disease, HYPP in horses, neonatal bovine diarrhea, & metabolic acidosis
what are the top causes of hypokalemia?
decreased intake, increased excretion/loss, & transcellular shifts
what are some examples of increased excretion/loss that lead to hypokalemia?
increased excretion/loss - feline CKD, loop diuretics, gi loss, & sweating in horses
what are some examples of transcellular shifts that lead to hypokalemia?
alkalemia, insulin or dextrose administration, & hypokalemia in cattle 3 months post partum
what is the ratio of chloride to sodium?
1:1 but it will be slightly lower than sodium in plasma
why should you always interpret chloride in conjunction with sodium?
they move together!!!!
what does it mean if the change in both sodium & chloride is roughly the same? what if it is different?
if the same - free water loss or gain, if different - acid-base disturbance or loss of Cl in excess of sodium
what are the top causes of hyperchloremia?
drug administration (potassium bromide) & hyperchloremic metabolic acidosis (secondary to renal disease)
what are the top causes of hypochloremia?
hypochloremic metabolic alkalosis, loss of Cl rich fluid
what are some causes of loss of chloride resulting in hypochloremia in dogs/cats? cattle? horses?
dogs/cats - gastric acid with high causes of vomiting so gastric outflow tract or proximal duodenal obstruction, cattle - abomasal outflow tract obstruction & renal disease, & horses - ptyalism, gastric reflux, & diarrhea
what drug can result in hypochloremia?
loop diuretics
what are the 3 forms of calcium?
50/55% free/ionized (not measured by chemistry), 35/45% protein bound mostly to albumin which is measured, & 5/10% complexed with anions that is not measured
if calcium is abnormal on a chemistry panel, what should you measure?
ionized calcium
in dogs, how can calcium be adjusted?
measured calcium - albumin + 3.5
T/F: changes in blood albumin affect total calcium but not ionized
true
what is a normally adjusted calcium?
change in the measured calcium likely due to change in albumin
T/F: changes in ionized calcium are physiologically significant
true
