Small Group: Potassium Regulation and Hypertension Cases Flashcards
High potassium levels stimulate _________ on the principal cells of the collecting duct.
NaK exchangers on the basolateral side
Leukocytosis can lead to pseudo-hyperkalemia or pseudo-hypokalemia. How?
In tubes without heparin, cells clot and lyse. Broken cells release potassium, artificially raising the K levels. In tubes without heparin, increased WBCs consume more potassium, so they will artificially lower K levels.
Dietary causes of hypokalemia are rare, because ___________.
the kidneys are very good at reabsorbing potassium
Any kind of hyper-_________ state can lead to hypokalemia.
aldosterone
What three mechanisms lead to low total-body potassium levels in DKA?
Acidosis
Low insulin
High glucose leads to solute drag of potassium into serum
Even though people with DKA have low total-body potassium, they have high ___________.
serum potassium
What are some manifestations of hypokalemia?
Arrhythmia
Muscle weakness
Rhabdomyolysis
What is kayexalate?
A resin that absorbs potassium and secretes sodium
Cardiac arrest is more likely to result from _______-kalemia.
hyper
_______-kalemia can cause rhabdomyolysis.
Hypo
Peaked T waves signify ________-kalemia.
hyper
How do people adapt to vasodilators?
By reflex tachycardia and increased sodium absorption
In a healthy person, renin should be __________ after administering furosemide.
high (because volume is down)
In a person with malignant hypertension, how does controlling blood pressure affect GFR in the short term and long term?
Immediately, decreasing hypertension will lead to decreased GFR because vascular lesions will prevent autoregulation. Long term, however, the kidneys adapt and GFR normalizes.
