Final answer:
In a patient with hyponatremia due to excessive diuretic use, a nurse should expect to find neurological manifestations, with decreased level of consciousness being a possible symptom.
Step-by-step explanation:
The nurse assessing for manifestations of hyponatremia in a client taking twice the prescribed dose of a diuretic should expect findings related to the dilution of sodium in the body due to excess water. Hyponatremia can result in neurological symptoms due to the swelling of neurons in the brain. Given the options provided, C: Decreased level of consciousness is a possible manifestation of hyponatremia. Other symptoms could potentially include confusion, headaches, nausea, and, in severe cases, seizures and coma. Increased fluid accumulation can also lead to other signs like edema or congestive heart failure, and loop diuretics themselves can inhibit the reabsorption of sodium and chloride ions in the kidneys, thereby increasing urine output.