1. Death: Manner, Cause and Mechanism Notes on page 69

2. What is death? • Simply put, the end of life • The irreversible cessation of circulation of blood • Heart stops beating and cannot be restarted • When the heart stops beating, the body cannot transport oxygen to all its cells and the cells start to die

3. Stages of death • Stoppage • Nerves, muscles, organs and the brain stop working because of the lack of oxygen • Autolysis • Breakdown of cells (cannot be restarted) • Cell membrane dissolves, enzymes and cell contents spill out and digest surrounding tissues

4. After death – the autopsy • Who performs the autopsy? • The pathologist (medical examiner, coroner) • Conducted to determine manner, cause and mechanism of death • Careful and detailed medical examination of a person’s body and organs • Each organ is removed and examined • Tissue samples are taken

5. Manner of death • The general ways a person can die • Natural – caused by interruption and failure of body functions resulting from age or disease • Accidental – caused by unplanned events • Suicide – occurs when someone purposefully kills oneself • Homicide – death of one person caused by another person • Undetermined – based on the facts of the case and the autopsy, the pathologist cannot determine manner of death

6. Consider these situations • A man with a heart condition is attacked and dies from a heart attack during the assault. Is the manner of death accident or homicide? • An elderly woman dies after being kept from receiving proper health care by her son. Is the manner of death natural or homicide? • A person has been found with an overturned, empty bottle of pills. Is the manner of death suicide or accidental?

7. Cause of death • The reason someone dies • Natural: heart disease, cancer, stroke, physical injury, heart attack, disease • Accidental: Car accident, fall from a ladder, struck by lightning • Suicide: Hanging, overdose, gunshot • Homicide: Bludgeoning, shooting, burning, drowning, strangulation, suffocation • Each cause of death brings about a physiological change in the body

8. Mechanism of death • The specific physiological change in the body that brought about the cessation of life • Example: If the cause of death was a shooting, the mechanism could be loss of blood (exsanguination) or cessation of brain function • Example: If the cause of death was massive trauma from a car accident, the mechanism could be pulmonary arrest (lungs stopped working) • Example: If the cause of death is a drug overdose, a cardiac arrhythmia usually occurs (change in the heart rate)