The person encounters adaptation problems in a changing environment especially in situations of health and illness. This follows the totality paradigm. Unhealthy or healthy as seen by the medical model is another example of totality or mechanistic paradigms. My view of health is not based as firmly on the medical model or is as fatalistic as Roy's. In this case, the doctor and the nurse have decided on a course of action for the patient in place of providing pre-op answers to questions, different options and letting the patient expand his ability to manage his state of health and himself.
Stimuli originate in the environment.
The environment is always changing and interacting with the person. Residual stimuli are beliefs, attitudes, experiences, traits which may be relevant but effects are indeterminate and therefore cannot be validated. The best example is the use of the PCA pumps for pain control. When instructed properly the patient has control over the amount of noxious, focal stimuli in his inner environment. The nurse uses activities to increase adaptive and decrease ineffective responses during illness and health.