Perioperative Database of Chinese Elderly Patients

The investigators aim to establish a prospective database of perioperative elderly patients from multiple regions and centers. Collected data involves postoperative complications of the central nervous system, cardiovascular system, kidney, respiratory system, infection, pain, and other perioperative complications. Based on the database, the investigators intend to explore: * The incidence and risk factors of perioperative morbidity and mortality in elderly patients; * Perioperative risk assessment methods and early warning models for elderly patients; * Practical, safe, and effective risk prevention and control system through subsequent studies.