Final answer:
The nurse should prioritize assessment for headache, irritability, and a decreasing level of consciousness, which indicate worsening cerebral edema due to administration of a hypotonic solution instead of the ordered hypertonic solution for cerebral edema.
Step-by-step explanation:
The priority assessment for the nurse after hanging a hypotonic solution instead of a hypertonic one for a client with cerebral edema would be:
Headache, irritability, and decreasing level of consciousness
Hypotonic solutions, when given to a patient with cerebral edema, can exacerbate the condition by causing fluid shifts out of the blood vessels into the brain cells, potentially worsening cerebral edema. This could manifest as symptoms such as headache, irritability, and a decreasing level of consciousness due to increased intracranial pressure. These symptoms are critical indicators that require immediate attention to prevent further complications related to cerebral edema.