The healthcare provider prescribes a 5% dextrose injection with 20 units of regular insulin for a client with a serum potassium level of 6.0 mEq/L (6.0 mmol/L) and glucose level of 180 mg/dL (10.0 mmol/L). Which evaluation is most important for the nurse to include in this client's plan of care? Reference Range: Potassium [3.5 to 5.0 mEq/L (3.5 to 5.0 mmol/L)] Glucose [74 to 106 mg/dL (4.1 to 5.9 mmol/L)]

A. Monitor and document strict intake and output: Monitoring intake and output is important for overall fluid balance but does not directly assess the urgent problem of hyperkalemia, which can cause life-threatening cardiac arrhythmias. B. Obtain a 12-lead electrocardiogram daily: A 12-lead ECG can detect changes caused by hyperkalemia, but daily monitoring is not sufficient for the rapidly changing potassium levels expected with insulin and dextrose therapy. C. Evaluate glucose levels before and after meals: Monitoring glucose is necessary due to insulin administration, but the immediate threat posed by hyperkalemia requires a higher priority focus on potassium levels. D. Assess the serum potassium level every 4 hours: Frequent monitoring of serum potassium is critical because insulin shifts potassium into cells, rapidly lowering serum levels, and both hypokalemia and persistent hyperkalemia can lead to serious cardiac complications.