Commonly known as "preoperative four tests", it refers to the related pathogenic examination of patients with hepatitis B, hepatitis C, AIDS and syphilis before operation to confirm whether the patients have or are infected with these diseases. The document11issued by the Health Department, Notice of the General Office of the Ministry of Health on Printing and Distributing Clinical Pathways of Eight Diseases, has clearly stipulated that screening for infectious diseases (hepatitis B, hepatitis C, syphilis and AIDS) must be done before operation, which is the basis for the hospital to carry out four preoperative examinations.

In the process of re-execution, some hospitals did not communicate well with patients, and even opened inspection bills without the consent of patients, which led to the incomprehension and rejection of patients and their families. This is a pity, but preoperative examination can not only effectively guide clinical medical staff to take a series of targeted protective measures to protect medical staff from the risk of occupational exposure, but also remind medical staff to handle the instruments and materials used in the operation according to the relevant regulations of the Ministry of Health, and at the same time provide each patient with a clean and safe.