Prioritizing Laboratory Values in Dehydration Assessment

A patient has presented to the emergency department with symptoms consistent with dehydration, including dry mucous membranes, decreased urine output, and a low blood pressure of 90/60 mmHg. The nurse has ordered laboratory tests, and the results show the following: sodium 150 mEq/L, potassium 3.5 mEq/L, and chloride 104 mEq/L. Given the patient's presentation and these laboratory values, which of the following laboratory results should the nurse prioritize in further assessments to evaluate the patient's risk of complications associated with dehydration?