A client waiting to receive dialysis seems confused and presents with hypertension, edema, shortness of breath, and weight gain. Which action should the nurse implement?

Choice A reason: Assessing for vertigo is not relevant to the client’s current presentation. Vertigo does not explain confusion, hypertension, edema, or shortness of breath. This option does not address the underlying pathophysiology. Choice B reason: Obtaining a pulse oximetry reading provides information about oxygenation, which is important given shortness of breath. However, the client’s confusion, hypertension, edema, and weight gain are more directly related to fluid overload and electrolyte imbalance, particularly hyperkalemia. Choice C reason: Determining serum potassium level is the most critical action. Clients awaiting dialysis often develop hyperkalemia due to impaired renal excretion. Hyperkalemia can cause confusion, muscle weakness, and life-threatening cardiac arrhythmias. Identifying potassium levels guides urgent interventions before dialysis. Choice D reason: Calculating daily sodium intake is useful for long-term management of fluid retention, but it does not address the acute symptoms of confusion, hypertension, and shortness of breath. Immediate assessment of potassium is more urgent than dietary review.