Hypokalemia quiz answer

Labs on presentation: Na 117, K 1.5, Normal renal function. Exam consistent with volume depletion. EKG changes consistent with hypokalemia. Hyponatremia is asymptomatic

Treatment?

A. Treat hyponatremia first and then hypokalemia

B. Treat hyponatremia and hypokalemia simultaneously

C. Treat hypokalemia first and then hyponatremia  

Any thoughts? What would you do?
Here is what you all said:

" C,  but I believe that, in practice, we'd probably end up doing B."

"I would think treat both. As you improve distal tubular flow with saline , hypokalemia can worsen"

"How about KCl, NaCl and DDAVP with water restriction."

"Treat hypokalemia first.”

”In this case the hyponatremia may be at least partly explained by the huge deficit in total body potassium stores, thus causing intracellular shift of sodium in exchange for potassium. Given that this patient is asymptomatic, option C is probably the safest. Aggressive repletion of K w/150-200 mEq daily for 2-3 days will be necessary to replete his K and the patient's Na may slowly improve as well."


"Treat hypokalemia with IV KCL (ECG abnormalities make it urgent). Repleting volume would probably take care of hyponatremia."

"Patient should only be treated for Hypokalemia first as hypokalemia correction itself will cause improvement in hyponatremia. The theory behind it is with K repletion, there is translocation of K in the cell and Na will move out. Mich. Halperin book has an excellent article on this."

I think all responded practically the right answer. Correction of hypokalemia is very important in setting of hyponatremia and one has to be watchful of not over correcting Na too fast in this setting as correcting the K will correct the Na as one of the commenters pointed out. There have been cases reported of osmotic demyelination from just aggressive correction of K leading to fast Na correction.

Ref:

http://www.ncbi.nlm.nih.gov/pubmed/20338465

http://www.ncbi.nlm.nih.gov/pubmed/8192171