Chapter 11: Death

1. Chapter 11: Death

2. How do we define Death? • Is a person with a heartbeat alive even if there is no brain activity? • Death is a process not an event • Physiologists: when the heart stops beating, the cells begin to die • O2 levels drop • Basic processes of the body fails • Nerves, muscles, organs stop working, Stoppage • Once enough cellular death occurs life cannot restart

3.  Medical Legal Death Investigators • Coroners are usually elected and are not required to be physicians. If an autopsy is needed, a coroner will frequently consult with a pathologist or forensic pathologist.  • Medical Examiner:is a physician and in most cases, trained to be forensic pathologists...  • An appointed medically qualified officer

4. Coroners. The coroner is also responsible for: • Identifying the body • Notifying the next of kin • Collecting and returning any personal belongings on the body to the family of the deceased • Signing the death certificate

5.  Medical examiner At the crime scene they may: • Examine and document injuries, wounds, etc. • Determine identity • Collect remains, body • Transport body • Work closely with law enforcement, detectives, etc.

6.  Medical examiner In the crime lab they may: • Perform autopsies • Determine identity if not found at crime scene • Examine and document injuries, wounds, etc. • Collect trace evidence • Determine manner of death (natural, homicide, suicide, accidental, undetermined) • Collect and interpret toxicological evidence

7.  Medical examiner In court they may: • Testify for the prosecution • Testify for the defense

8. Medical Legal Death Investigators • Examination of the deceased, Autopsy • Necropsy • Investigations normally are called upon when the death is: • Sudden • Violent • Unexplained deaths • Will Investigate • Manner • Cause • And mechanism of death

9. Medical Legal Death Investigators • Questions sought to answer: • Who was the person? (identification) • When did they die? (the date of death) • Where did they die? • How did they die? (the medical cause of death) • By what means did they die? • (the Manner of death; this can be either natural causes, accident, homicide, suicide, or undetermined)

10. Types of Death??? • Manner of Death, • Natural, Accidental, Suicidal, Homicidal, Undetermined • Cause of death:The reason someone dies • Disease: physical injury, stroke, heart attack • bludgeoning, shooting, hanging suffocation, • Mechanism of Death: the specific change in the body that brought about the cessation of life • exsanguinations (Blood loss) • Pulmonary arrest (Heart stoppage) • hemorrhage, cardiac arrhythmia, cerebral hypoxia, sepsis

11. Do Now: • What are the five Manners of Death?,

12. Forensic Pathology • Autopsy performed to establish cause of death. • Classifications theManner of Death *Natural *Homicide *Suicide *Accident *Undetermined

13. Manner of Death • Five ways people die • Natural • Interruption and failure of bodily function resulting from age or disease • Accidental • Unplanned event • Suicidal • A person purposely kills oneself • Homicidal • Death of one person caused by another • Undetermined • Suicidal or accidental • Pills, guns

14. Odd Manners of death • When death is due to a combination of natural and unnatural events, preference is generally given to the non-natural cause; example: a man suffers a myocardial infarction while swimming in the ocean, loses consciousness, and drowns; the manner of death is ruled accident, as he may potentially have survived if the fatal myocardial infarction had occurred on land • The “but-for” principle asks the question “But for the inciting injury (or event), would the decedent still be alive?” • In most jurisdictions, deaths due to motor vehicle collisions are considered accidental in manner • Deaths due to complications of medical therapy that are reasonably expectable (e.g. neutropenia due to chemotherapy, digoxin toxicity) are considered natural • Deaths due to improper use of medical devices or improper therapy (e.g. malfunctioning morphine drip, failure to repair obvious arterial injury inflicted during surgery) are considered accidental • While acute alcohol or drug toxicity is considered an accidental death, • deaths due to consequences of chronic substance abuse (hepatic cirrhosis due to ethanol abuse, endocarditis secondary to IV drug use) are conventionally considered natural in manner

15. Types of Death??? • Manner of Death, • Natural, Accidental, Suicidal, Homicidal, Undetermined • Cause of death:The reason someone dies • Disease: physical injury, stroke, heart attack • bludgeoning, shooting, hanging suffocation, • Mechanism of Death: the specific change in the body that brought about the cessation of life • exsanguinations (Blood loss) • Pulmonary arrest (Heart stoppage) • hemorrhage, cardiac arrhythmia, cerebral hypoxia, sepsis

16. Do Now: Identify what is the Manner and mechanism of Death? • Case 1: A man with a heart condition is attacked and dies from a heart attack during the assault. • Case 2: An elderly woman dies after being kept from receiving proper health care by her son.

17. Do Now: Identify what is the Manner of Death? • Case 3: A man is struck by an intoxicated driver's car and severely injured. The paramedics arrive and transport him to the hospital, where he dies as a result of his injuries. The blunt trauma from the car may have caused lethal brain injuries, and the driver may be charged in the man's death. • On the other hand, if the injuries weren't that severe, and the victim died from internal bleeding that paramedical and hospital personnel failed to recognize and treat appropriately, who then is responsible for the man's death? • In each of these scenarios the cause of death is blunt trauma from the automobile impact, but the mechanism is either a brain contusion or exsanguination

18. Top 15 Causes of Death in the US

19. Please provide the Manner, Cause and Mechanism of Death for John Locke. Remember the season finale, he was hung. • Manner of Death • Cause of death • Mechanism of Death

20. Mechanism of death • A shot in the heart, is a cause of death that can lead to one of several mechanisms of death: • exsanguination (bleeding to death) • sepsis (infection that enters the blood stream). • The victim of a skull fracture can die from: • direct trauma to the brain (cerebral contusion) • bleeding into the brain itself (intracerebral bleed) • bleeding around the brain (subdural or epidural hematoma) • all of which can lead to compression of the brain and result in a stoppage of breathing (asphyxia). Again, one cause can lead to death by several mechanisms. • Conversely, one mechanism can result from several different causes. A gunshot wound, stabbing, bleeding ulcer, or a bleeding lung tumor can cause you to bleed to death. In each case, blood loss and shock are the abnormal physiological changes.

21. Please provide the Manner, Cause and Mechanism of Death for John Locke. • Manner of Death: Homicide • Cause of death: asphyxia • Mechanism of Death: hypoxia, • reduction of oxygen supply to a tissue

22. Categorizing Time of Death Time of death is categorized in three ways: • Physiological time of death: The point at which the deceased's body - including vital organs - ceased to function. • Estimated time of death: A best guess based on available information. • Legal time of death: The time at which the body was discovered or physically pronounced dead by another individual. This is the time that is shown - by law - on a death certificate.

23. Homework:Research and Identify How investigators estimate time of death..There are about 9 ways

24. Estimating Time of Death Ways of Estimating Actual Time of Death:

25. Estimating Time of Death 9 Ways of Estimating Actual Time of Death: • Rigor mortis • Livor mortis: (Lividity) • Algor mortis: Body Core Temperature • Potassium levels in vitreous humor + Clouding of the cornea • Stomach Contents • Evidence of Decompositional Process • Presence/absence of purge fluids • Drying of the tissue • Insect Larval Instars http://www.dundee.ac.uk/forensicmedicine/llb/timedeath.htm#Time%20of%20Death

27. Nysten's Law • In 1812, a French pediatrician named Pierre Nysten recorded his observation that rigor mortis follows a downward progression that begins in the upper region of the body, around the face and head, and travels in a set pattern down to the rest of body and the extremities. • Known as Nysten's law, this principle likely reflects the fact that rigor mortis -- while affecting all muscles in the same way at the same time -- becomes noticeable first in small muscle groups, such as those around the eyes, mouth and jaws, and becomes pronounced somewhat later in the larger muscles of the lower limbs.

28. 1. Rigor Mortis • (L: rig- stiff; mortis—death) • Muscles become rigid • Starts w/I 2 hours but gone after 48 hours • After 48 hours muscles begin to autolysis (dissolve) • “The biochemical cause of rigor mortis is hydrolysis of ATP in the muscle tissue, the chemical energy source required for movement. Myosin molecules devoid of ATP become permanently adherent to actin filaments and muscles become rigid.” • http://study.com/academy/lesson/rigor-mortis-definition-timeline-stages.html

29. 1. Rigor Mortis Rigor mortis occurs because metabolic activity continues in the muscle after death. • Adenosine triphosphate (ATP) is needed to maintain the postmortem relaxation of the muscles. • So long as the store of glycogen (sugar) in a muscle is sufficient to permit the regeneration of ATP by the formation of lactic acid, the muscle remains lax. • When its store of glycogen is exhausted, the concentration of ATP falls, and the muscle becomes rigid because of the formation of abnormal links between actin and myosin. • The rigor mortis persists until these links are destroyed by advancing autolysis.

30. Live muscles fiber slide back and forth; in 48 hours after death, the muscles become locked in a fixed position

31. Question: Why would a corpse have goose bumps? • Rigor mortis of the erector pilae can result in postmortem "goose flesh."

32. Rigor Mortis

33. Rigor Mortis

34. Rigor Mortis

35. Rigor Mortis

36. Rigor Mortis

37. What are some factors affecting Rigor mortis ? • Ambient temperature, • Cooler the body the slower to onset of rigor • Person’s weight • fat stores more oxygen and slow rigor • Type of clothing • Helps keep the body warm • Illness • Dies with a fever? What would you expect? • Hypothermic? What would you expect? • Level of physical activity • Struggling before death rigor, What would you expect? • Sun exposure, • Sun tanner? What would you expect?

38. Live muscles fiber slide back and forth; in 48 hours after death, the muscles become locked in a fixed position

39. Estimating Time of Death 9 Ways of Estimating Actual Time of Death: • Rigor mortis • Livor mortis: (Lividity) • Algor mortis: Body Core Temperature • Potassium levels in vitreous humor + Clouding of the cornea • Stomach Contents • Evidence of Decompositional Process • Presence/absence of purge fluids • Drying of the tissue • Insect Larval Instars • Environ http://www.dundee.ac.uk/forensicmedicine/llb/timedeath.htm#Time%20of%20Death

40. 2. Livor mortis or (postmortem lividity)L: liv-bluish) * Onset at about 2 hours, permanent at 8 hours Is a settling of the blood in the lower portion of the body ** Causing a purplish red discoloration of the skin. ***Discoloration does not occur in the areas of the body that are in contact with the ground or another object,

41. 2. Livor mortis area of blanching

42. What caused this? Livor mortis in an anterior position. The area of blanching across the chest and abdomen resulted from the decedent lying on top of his left arm and right hand.

43. Still on Skin color • Tardieu spots: are petechiae and purpuric hemorrhages that develop in areas of dependency secondary to the rupture of degenerating vessels under the influence of increased pressure from gravity • Petechiae: a small red or purple spot caused by bleeding into the skin via capillaries • As the postmortem interval lengthens, Tardieu spots develop in areas of lividity, such as this individual's shoulder area, as decomposing capillaries rupture.

44. Prolonged Straining + Injuries • Tiny petechiae of the face, neck and chest can be caused by prolonged straining during activities such as: • Crying, Coughing, Vomiting, Childbirth, Weightlifting Diseases: • Mononucleosis, Rocky Mountain spotted fever, Scarlet fever, Sepsis. Strep throat Injuries or sunburns • Child abuse involving strangulation or smothering can cause petechiae in the face and eyes. • Biting, Spanking, Crush injuries during car crashes, can result in petechiae of the face, neck and chest.

45. Still on Skin color • Tache noire (täsh nô·är′ )If the eyes remain open after death, the areas of the sclera exposed to the air dry out, which results in a first yellowish, then brownish-blackish band like discoloration zone called TACHE NOIRE • 7 to 8 hours after death

46. Algor Mortis 3. Algor mortis

47. 2. Algor mortis (L: algor—coolness) • the reduction in body temperature following death. • a steady decline until matching ambient temperature • A measured rectal temperature can give some indication of the time of death. • Newton's law of cooling states that the rate of cooling of a body is determined by the difference between the temperature of the body and that of its environment. • The Glaister equation: 1-1 1/2 degree F per hour • Algor mortis is usually the first sign of death, beyond the obvious, and is then followed by rigor mortis. As decomposition occurs the internal body temperature tends to rise again. WHY?????

48. Calculating Rigor: MathematicallyQuestions: What are some Factors that would affect Algor Mortis? • Ambient temperature • Wind? • Excess body fat? • Clothing • etc

49. Hour: 0 --------------------12---------------- = ambient Rate: 0.78oC/hour 0.39oC/hour Temp: 37oC 27.64 oC Decedent body Temp= 36oC 37oC - 36 oC = 1oC (1oC x0.78oC/hr)= 1.28 hours (.28 hours x.60min/1hr) 16.8mins 1 hr and 6.8min

50. DO NOW:What is the ETOD for a person with a core temp of 34.2oC ?