Final answer:
The nurse should document the elderly client's hand tremors as an 'intention tremor,' which is visible during deliberate movements and indicates issues with the nervous system.
Step-by-step explanation:
When observing the elderly client with uncontrollable hand tremors while reaching for a glass of water, the nurse should document this as an intention tremor. Intention tremor is a type of tremor that becomes more apparent when a person attempts to perform a deliberate action, which can be tied to issues in the cerebellum or connections within the nervous system. Conditions such as muscle flaccidity involve a lack of muscle tone and are characterized by hypotonia, whereas a transient ischemic attack (TIA) involves temporary neurological dysfunction due to a lack of blood flow, and sensory dysfunction would pertain more to deficits in sensory perception, not motor function.