Legal analysis: the patient must have the signature of his family to perform the operation. First, because some patients go to the hospital for surgery without their families' knowledge, in this case, the patients are left unattended, and there is no family to take care of the problems during and after the operation. Secondly, patients' families also have the right of informed consent, and medical staff have the obligation and responsibility to communicate with patients' families about their illness in order to gain their support and trust. Thirdly, after general anesthesia, once there are unpredictable risks after losing consciousness, it is necessary to communicate with the patient's family members, and then the next diagnosis and treatment activities will be carried out after the patient's family members sign and confirm.

Legal basis: Article 36 of the Interim Measures for Technical Appraisal of Medical Accidents, the expert appraisal team shall comprehensively analyze the role of medical negligence in causing the damage consequences of medical accidents, the patient's original disease status and other factors to determine the degree of responsibility for medical negligence. The degree of responsibility for medical negligence in medical accidents is divided into:

(1) Full responsibility means that the damage consequences of medical accidents are completely caused by medical negligence.

(2) The main responsibility means that the damage consequences of medical accidents are mainly caused by medical negligence, and other factors play a secondary role.

(3) Secondary liability means that the damage consequences of medical accidents are mainly caused by other factors, and medical negligence plays a secondary role.

(4) Minor liability means that most of the damage consequences of medical accidents are caused by other factors, and medical negligence plays a secondary role.