It's not that you can't catch a cold during anesthesia, but that it's not suitable for operation in cold conditions and should be postponed. Whether the patient has a cold is the standard question for our anesthesiologist to visit before operation. Because if you catch a cold, that is, a preoperative respiratory infection, the possibility of respiratory complications in books and after surgery will be much higher than normal. For example, there are a lot of secretions during the operation, which affects the patient's ventilation. This is a very dangerous situation. Because of a cold, the whole respiratory tract is in a highly sensitive state and sensitive to external stimuli. Routine insertion of endotracheal tube under general anesthesia and inhalation of anesthetic are also external stimuli to respiratory tract. Therefore, we usually do surgery after the cold is cured 1-2 weeks, and the child has to postpone it. When I was an intern, my parents had laryngeal spasm after taking off the laryngeal mask because a boy caught a cold, and insisted on the operation! Very, very dangerous. Of course, this is all elective surgery. To be on the safe side, if it is an emergency operation, it is important to save your life, and the operation will be done. In addition, the ability to resist colds will also decline, and white blood cells will deal with viruses and secondary bacterial infections, which is unfavorable to the prognosis.