Final answer:
According to Piaget's preoperational stage, the nurse can best help a 6-year-old child cope with the stress of upcoming surgery through play that simulates the events they will experience.
Step-by-step explanation:
The nurse is caring for a 6-year-old child who is scheduled for outpatient surgery. According to Jean Piaget's theory of cognitive development, the most effective way for the nurse to help the child cope with stress is by using play as a means of familiarizing the child with the events he will experience.
This approach aligns with Piaget's preoperational stage of cognitive development, which occurs from approximately 2 to 7 years old, where children learn to use symbols and engage in pretend play. Using play to simulate the events related to the surgery can help the child understand and mentally prepare for the experience in a way that matches their cognitive abilities.