New York State Basic Emergency Medical Technician (EMT-B) Practice Exam

What is dependent lividity?

1. Rigor mortis in deceased individuals

2. Pooling of blood in body parts due to gravity after death

3. A sign of acute trauma

4. A state of unresponsiveness

The correct answer is: Pooling of blood in body parts due to gravity after death

Dependent lividity refers to the pooling of blood in the body parts that are closest to the ground after death. This process is a result of gravity causing blood to settle in the lower areas of the body, which can create a purplish discoloration of the skin in those regions. This phenomenon begins shortly after the heart stops beating and can typically be observed within 20 minutes to three hours post mortem. The patterns of lividity can provide significant information about the positioning of the body at the time of death, which can be crucial in forensic investigations. Rigor mortis, which involves the stiffening of muscles after death, is a separate post-mortem change and is distinct from livor mortis (the technical term for dependent lividity). Signs of acute trauma pertain to injuries sustained prior to death and do not directly relate to the processes of lividity, while a state of unresponsiveness is indicative of a living person who may be in a coma or unresponsive state due to medical conditions but is not relevant to the post-mortem context. Understanding dependent lividity helps EMTs and first responders in providing accurate assessments in death investigations.