What symptom indicates the presence of a hematoma?

The presence of a hematoma is characterized by localized swelling and a firm ridge or fullness at the edges of the hematoma. The swelling occurs as blood accumulates outside of blood vessels within the body's tissues, leading to inflammation and mechanical effect in the surrounding area. A hard ridge may become palpable at the edges as the hematoma organizes and as the blood begins to clot and consolidate. This tactile firmness, combined with the swelling, is a direct indication of a localized collection of blood, confirming the diagnosis of a hematoma.

While increased heart rate can sometimes occur as a physiological response to pain or anxiety, it is not a definitive indicator of a hematoma. Symptoms like nausea, vomiting, and excessive sweating can be associated with various medical conditions but are not specific to the presence of a hematoma. Thus, the hallmark symptom suggesting a hematoma's presence is the combined observation of swelling and a hard ridge felt at the edges.