FromtheGroundUp

The physician orders the following order for fluid replacement on a patient diagnosed with acute gastroenteritis: Start D5 ½NS with 20 mEq KCL at maintenance. Before hanging the IV fluid which of the following assessments would be most important? The question above has two answer choices that are giving me trouble. The first one is documented urine output and the other is Baseline EKG. I'm thinking baseline EKG given the fact that potassium has cardiac effects and you'd want a baseline to determine what's abnormal but I also think urine output is important because you'd want the child to be able to excrete the solutes.

Alright, so we have to complete medication lists with a patient scenario-My patient is hyponatremic. He has normal potassium levels but is receiving Potassium Chloride 10 mEq extended release tablet 3 times daily PO. I don't understand why this patient is on a potassium supplement if his potassium level is unaffected. I was thinking it had something to do with the sodium-potassium pump and reciprocal relationship sodium and potassium have as well as the fact that the patient is on a laxative which can decrease potassium levels as well. Can someone help me think through this?