Final answer:
In the context of a patient taking lithium for bipolar disorder, slurred speech is a concerning symptom that should be reported to the provider as it may indicate lithium toxicity.
Step-by-step explanation:
When a nurse is collecting data from a client who is taking lithium to treat bipolar disorder, certain findings must be monitored closely due to the narrow therapeutic range and potential toxicity of lithium. Of the options provided, slurred speech is a finding that should be reported to the provider. Slurred speech can be a sign of lithium toxicity, which is a serious and potentially life-threatening condition.
On the other hand, bloating is a common side effect and usually not critical; a white blood cell (WBC) count of 8500/mm3 is within the normal range; and a sodium level of 140 mEq/L is also within the normal range and is not necessarily related to lithium toxicity. Therefore, the slurred speech is the most concerning symptom that warrants immediate communication with the healthcare provider.