Bulging flanks

In medicine, bulging flanks are a sign of ascites. If the sides of the abdomen are seen to bulge outward in an unusual fashion on a patient (most easily observed from the patient's foot end), they are likely to have fluid in the abdomen. This occurs if a significant amount of free fluid is present. The fluid collects around the flanks due to gravity, causing them to bulge somewhat like a water balloon.

See also