The nurse is caring for a client that was admitted with nausea/vomiting, restlessness, dry oral mucosa, and extreme thirst. The nurse understands that the client has which electrolyte imbalance?

A. Hyperphosphatemia: Elevated phosphate levels are commonly associated with renal failure and can lead to hypocalcemia due to calcium-phosphate binding. Clinical manifestations often include muscle cramps, tetany, and sometimes soft tissue calcifications. Intense thirst, dry mucous membranes, and dehydration are not characteristic of hyperphosphatemia. B. Hyperkalemia: Hyperkalemia primarily affects cardiac and neuromuscular function, presenting with symptoms such as muscle weakness, paresthesia, and potentially life-threatening dysrhythmias. Gastrointestinal symptoms may include diarrhea rather than nausea and vomiting, and it does not typically cause pronounced thirst or dry mucosa. C. Hypocalcemia: Hypocalcemia is associated with neuromuscular excitability, including tetany, muscle spasms, seizures, and positive Chvostek’s or Trousseau’s signs. It does not present with dehydration-related symptoms such as extreme thirst or dry oral mucosa. D. Hypernatremia: Hypernatremia reflects a relative water deficit leading to increased serum sodium concentration. It commonly presents with intense thirst, dry mucous membranes, restlessness, and neurologic changes due to cellular dehydration, especially in the brain. Nausea and vomiting may also occur, and the symptoms reflects dehydration and hyperosmolarity.