First of all, we need to know that general anesthesia refers to endotracheal intubation general anesthesia, the following cases can not be on the general anesthesia: First, laryngeal edema patients, because patients with laryngeal edema of the vocal folds are in a narrowed or occluded state, the tracheal catheter can not pass the narrowed or occluded vocal folds, the solution is to carry out a tracheotomy, and then the surgical anesthesia. Second, suffering from severe hypertension, not regular medication to control blood pressure patients, general anesthesia process hemodynamics is extremely unstable, easy to lead to myocardial ischemia, cerebral ischemia, serious cases can cause myocardial infarction, cerebral infarction. Third, hyperthyroidism is not controlled by stable patients, general anesthesia process is easy to cause hyperthyroidism crisis, serious cases will lead to cardiac arrest and rescue. Fourth, acute myocardial infarction patients, general anesthesia is easy to cause cardiac arrest. Fifth, acute cerebral infarction patients, general anesthesia will aggravate cerebral ischemia, and even lead to new cerebral infarction.