This is because the effect of anesthesia is not completely eliminated, coupled with the analgesic treatment given on the day of surgery and the fact that the gastric tube has not been removed. After the gastric tube is removed on the second day after surgery, you can drink a small amount of water after you are fully awake, and if there is no adverse reaction, you can drink a small amount of water several times, usually not more than 500ml per day. Then, according to the intestinal sounds and waiting for the anal venting, you can drink normally, which means that you do not need to control the amount of water, and you can drink whenever you want. After deflation, you can start to eat rice soup, porridge, juice and other liquid food.