An 8-year-old child is brought to the physician's office by his mother. The mother is concerned because the boy has a fever, vomited twice, and slept all day yesterday with the curtains closed. The child complains of headache and nausea and has a temperature of 103°F (39.3°C). The nurse observes the child has a petechial rash on the trunk of the body. Which of the following assessments is MOST important for the nurse to perform?
1. Grasp the child's hands, and ask him to squeeze the nurse's hands.
2. Stroke the plantar surface of the child's foot with a reflex hammer.
3. Gently flex the child's head and neck onto the chest.
4. Have the child stand with his eyes closed, his arms at his sides, and his feet and knees close together.