Which of the following is a potentially lethal symptom of strangulation?

Involuntary urination or defecation is a potentially lethal symptom of strangulation due to the body's extreme stress response. Strangulation restricts blood flow to the brain, which can lead to loss of consciousness and disruption of bodily functions, including control over bladder and bowel. This loss of control can indicate a severe level of distress and possible loss of brain function, making it a critical marker in assessing the severity of strangulation injuries.

The presence of this symptom raises significant concern for the victim's current state and overall health, as it can be associated with hypoxia (lack of oxygen) and significant trauma to the central nervous system. Such indicators should prompt rapid medical evaluation and urgent care, as they suggest life-threatening consequences.

In contrast, while symptoms like chest pain, bluish skin discoloration, and severe headache can also arise from strangulation and indicate distress, they are not as directly linked to lethal outcomes as involuntary urination or defecation. Therefore, understanding the implications of these symptoms helps in recognizing the severity of the situation and the need for immediate intervention.