Q: How to distinguish between traumatic bloody ascitic tap and non-traumatic bloody ascitic fluid?


Answer:

Bloody ascitic fluid from a traumatic tap will be heterogeneously bloody, and tend to clot. Nontraumatic bloody fluid is usually homogeneously red and does not clot because the blood has already been lysed after clotting within sac.

A minimum of 10,000 red blood cells/µL is required for ascitic fluid to appear pink, and more than 20,000 red blood cells/µL to produce distinctly blood-tinged fluid.