Final answer:
The nurse should obtain a lithium level to confirm therapeutic drug levels and ensure the patient is taking the medication, as the symptoms observed are signs of bipolar disorder not being properly managed. These symptoms can affect the patient's everyday functioning and cognitive performance.
Step-by-step explanation:
The nurse's best intervention for a patient with bipolar disorder who exhibits increased restlessness, pressured speech, flight of ideas, and reduced sleep even after receiving lithium treatment is to consider the need to obtain a lithium level.
This is important to ensure the patient is maintaining therapeutic drug levels and is not experiencing toxicity. In addition, the patient may not be swallowing the medication, which is critical to address to ensure proper treatment adherence. The nurse should monitor the patient closely for symptoms of bipolar disorder, as these can directly impact a patient's cognitive performance, ability to concentrate, memory, and attention spans, ultimately affecting the patient's overall well-being.
It is also essential for the health care provider to understand that symptoms such as fatigue, lack of sleep, and stress associated with bipolar disorder could lead to lasting challenges in the patient's daily functioning, even after the manic or depressive episode passes.