Step I DKA and K+

[metalmd06]

Does acute DKA cause hyperkalemia, or is the potassium normal or low due to osmotic diuresis? I get the acute affect of metabolic acidosis on potassium (K+ shifts from intracellular to extracellular compartments). According to MedEssentials, the initial response (<24 hours) is increased serum potassium. The chronic effect occuring within 24 hours is a compensatory increase in Aldosterone that normalizes or ultimatley decreases the serum K+. Then it says on another page that because of osmotic diuresis, there is K+ wasting with DKA. On top of that, I had a question about a diabetic patient in DKA with signs of hyperkalemia. Needless to say, I'm a bit confused. Any help is appreciated.

 

[FutureDoc4]

I remember this being a tricky point:

1) DKA leads to a decreased TOTAL body K+ (due to diuresis) (increase urine flow, increase K+ loss)

2) Like you said, during DKA, acidosis causes an exchange of H+/K+ leading to hyperkalemia.

So, TOTAL body K+ is low, but the patient presents with hyperkalemia. Why is this important? Give, insulin, pushes the K+ back into the cells and can quickly precipitate hypokalemia and (which we all know is bad). Hope that is helpful.

 

[Cooolguy]

DKA-->Anion gap M. Acidosis-->K+ shift to extracellular component--> hyperkalemia-->symptoms and signs

DKA--> increased osmoles-->Osmotic diuresis-->loss of K+ in urine-->decreased total body K+ (because more has been seeped from the cells)

--dont confuse total body K+ with EC K+



Note: osmotic diuresis also causes polyuria, ketonuria, glycosuria, and loss of Na+ in urine--> Hyponatremia

DKA tx: Insulin (helps put K+ back into cells), and K+ (to replenish the low total potassium

Hope it helps

 

[metalmd06]

Thanks a lot, both of you.

 

[kunfu]

I remember this being a tricky point:

1) DKA leads to a decreased TOTAL body K+ (due to diuresis) (increase urine flow, increase K+ loss)

2) Like you said, during DKA, acidosis causes an exchange of H+/K+ leading to hyperkalemia.

So, TOTAL body K+ is low, but the patient presents with hyperkalemia. Why is this important? Give, insulin, pushes the K+ back into the cells and can quickly precipitate hypokalemia and (which we all know is bad). Hope that is helpful.

Future doc nailed this. Also in terms of treatment IV fluids FIRST then insulin with 5% dextrose I believe is the standard of care.

 

[turkeyjerky]

Future doc nailed this. Also in terms of treatment IV fluids FIRST then insulin with 5% dextrose I believe is the standard of care.

for sho', IV fluids (ns) are the most important component of treatment--this will actually be extremely beneficial even without insulin. then you supplement with dextrose once the glucose hits 200 and K+ once it hits 5.