Final answer:
The nurse aide should report the incident of the resident being slapped by their wife to the charge nurse immediately, as it could indicate potential abuse and healthcare providers are responsible for patient safety.
Step-by-step explanation:
If a nurse aide enters a room and observes a resident's wife slap the resident, even if the resident does not appear to be upset or hurt, the nurse aide should report the observation to the charge nurse immediately. This action is necessary as it could be a sign of potential abuse, and it is part of the healthcare provider's responsibility to ensure the safety and well-being of patients. Additionally, healthcare facilities have protocols and policies in place for handling such incidents, which typically include reporting to a supervisor for further assessment and intervention.