Mobility turbidity is a unique clinical sign when a large amount of fluid is accumulated in the abdominal cavity. If the patient is found to have a positive mobility turbidity, it often suggests that the abdominal fluid accumulation is greater than 1,000 ml or more. General mobile turbidity sound examination steps are as follows: 1, ask the patient to take the lying position, the whole body relaxation, hands on both sides of the body. At this time, the liquid gathered in the abdominal cavity on both sides, the intestinal tube floating in the abdominal fluid on the surface, in the navel center to both sides of the percussion, the percussion sound can be gradually changed from the drum tone to turbidity. 2, the patient is asked to take the side position, the water in the abdominal cavity due to the effect of gravity in the abdominal cavity on the side of silt accumulation. The intestinal tube is still floating in the water, percussion from the outside to the inside of the percussion sound can be changed from turbid to drum sound.