Postoperative cognitive dysfunction (POCD) occurs mainly in aged patients. The mechanism of POCD is not clear yet and no effective therapy method. In the present study, we conducted a single-center observational prospective cohort trial in elder patients who undergoing hip joint replacement surgery with general anesthesia to test our hypothesis that preoperative chronic pain is one of the risk factors of POCD after major joint replacement surgery.
The purpose of this study is to investigate whether preoperative pain is the risk factor of POCD in elder patients.