Fasting can be done for 8 hours for liver, gallbladder, pancreas, spleen and kidney ultrasound, and you should follow the doctor’s arrangement before doing the specific examination. Liver, gallbladder, pancreas, spleen and kidney ultrasound, also known as abdominal ultrasound, mainly observes the size and location of the liver, gallbladder, pancreas, spleen and kidney, and checks for stones, tumors or inflammatory lesions, etc. It can check for liver cysts, gallstones, pancreatic occupancy, kidney tumors and so on. The day before the ultrasound examination, you should eat a light diet, and on the day of the examination, you should fast, abstain from water and food, which is conducive to a clearer liver and gallbladder image. When fasting, bile is mainly stored in the gallbladder, and the more bile there is, the more the gallbladder fills up, so that it can be clearly shown when doing ultrasound. After eating, bile secretion is promoted and the gallbladder shrinks and becomes wrinkled, which may hide some small stones in the folds, which is not conducive to diagnostic examination. After eating, the volume of stomach increases, which may cover the pancreas, which is unfavorable for observing the pancreas and may lead to missed diagnosis. Before the ultrasound examination of liver, gallbladder, pancreas, spleen and kidney, you should have a good rest, avoid overwork and do not drink alcohol. For diabetic, old and frail patients, fasting for too long may lead to hypoglycemia, and you should communicate with your doctor in advance and arrange the time reasonably.