A nurse in an emergency department is caring for a client who has a closed head injury. Which of the following actions should the nurse take first?

A. Determine the client's Glasgow Coma Scale score: Assessing the client’s neurological status using the Glasgow Coma Scale (GCS) is the first action because it establishes a baseline for consciousness, guides priority interventions, and helps detect early deterioration. Rapid neurological assessment is critical in closed head injuries to identify life-threatening changes. B. Prepare the client for an MRI of the brain: Imaging is important for diagnosis, but it is not the first action. The client’s neurological status must be assessed and stabilized before sending them for diagnostic procedures to ensure safety during transport and imaging. C. Administer mannitol IV bolus to the client: Mannitol is used to reduce intracranial pressure, but administering it before assessing neurological status may not be indicated. Treatment should be guided by the assessment findings, including GCS and signs of increased intracranial pressure. D. Insert an indwelling urinary catheter for the client: Catheterization may be necessary for monitoring output in critically ill clients, but it is not a priority over assessing neurological status. Maintaining airway, breathing, and circulation, and assessing neurologic function take precedence in head injury care.