The drugs used in the implementation of general anesthesia, especially analgesics, have varying degrees of nausea and vomiting, and various protective reflexes of patients under general anesthesia are weakened or even disappeared by the inhibition of anesthetic drugs, so if patients do not fast from food and water before surgery, food and water in the stomach will reflux to the pharynx and then enter the respiratory tract by mistake, which will cause organ blockage and asphyxiation, and can seriously Therefore, the intake of any food and beverage must be prohibited before the implementation of general anesthesia, and it is usually considered that fasting and water should be prohibited at midnight the day before surgery, and children or infants are prohibited from breastfeeding or using solid food 6 hours before surgery.