Fluctuation

Fluctuation, lluctuatio (from Latin fluctuare - to flow, to undulate), a symptom of great importance in the examination of surgical patients. F. appears when touching a cavity filled with fluid and possessing elastic yielding walls (abscesses, cysts, hematomas, ascites, etc.). To determine the presence of F., one or more fingers of one hand are placed on the area of the body being examined, then the tissues are given light pushes by the fingers of the other hand, applied at some distance from the first, thus causing the liquid contents of the cavity to move. The fingers of the first hand perceive the sensation of a wave impact from the rising liquid. F. is felt especially strongly inside the cavity in which the liquid is under only slight pressure. In accumulations of liquid in large cavities with very yielding walls (abdominal cavity - ascites, large ovarian cysts), the presence of F. should be tested by applying palms on opposite sides of the cavity. In these cases, the movement of the fluid wave is often visible to the eye (the so-called undulation). F. should not be confused with false F., which appears when palpating very soft tumors (lipoma), as well as elastic tissues, but not fluids. In doubtful cases, puncture with subsequent aspiration with a syringe is sometimes indicated. In gynecological cases, F. is determined by the examiner through a finger in the vagina. First, a certain softness and yielding of the protrusion into the posterior fornix is felt, and second, the finger perceives the sensation of a counter-thrust after sudden light pressure on this protruding soft area.