Chapter 11: Death.

Chapter 11: Death

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

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

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

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.

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

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

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

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)

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

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

Forensic Pathology Autopsy performed to establish cause of death.
Classifications the Manner of Death *Natural *Homicide *Suicide *Accident *Undetermined

Manner of Death Five ways people die Natural Accidental Suicidal
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

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

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

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.

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

Top 15 Causes of Death in the US
FORMAL NAME INFORMAL NAME % ALL DEATHS (1) Diseases of the heart heart attack (mainly) 28.5% (2) Malignant neoplasms cancer 22.8% (3) Cerebrovascular disease stroke 6.7% (4) Chronic lower respiratory disease emphysema, chronic bronchitis 5.1% (5) Unintentional injuries accidents 4.4% (6) Diabetes mellitus diabetes 3.0% (7) Influenza and pneumonia flu & pneumonia 2.7% (8) Alzheimer's Disease Alzheimer's senility 2.4% (9) Nephritis and Nephrosis kidney disease 1.7% (10) Septicemia systemic infection 1.4% (11) Intentional self-harm suicide 1.3% (12) Chronic Liver/Cirrhosis liver disease 1.1% (13) Essential Hypertension high blood pressure 0.8% (14) Assault homicide 0.7% (15) All other causes other 17.4%

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

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.

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

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.

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

Estimating Time of Death
Ways of Estimating Actual 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

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.

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.”

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.

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

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

Body becomes stiff and stiffness moves down body.
Rigor Mortis Time After Death Event Appearance Circumstances 2–6 hours Rigor begins Body becomes stiff and stiffness moves down body. *Stiffness begins with the eyelids and jaw muscles after about three hours, *then center of body stiffens, *then arms and legs. (12 hours)

Rigor Mortis Event Appearance Circumstances Time After Death
2–6 hours Rigor begins Body becomes stiff and stiffness moves down body. *Stiffness begins with the eyelids and jaw muscles after about three hours, *then center of body stiffens, *then arms and legs. (12 hours) 12 hours Rigor complete Peak rigor is exhibited. Entire body is rigid.

Rigor Mortis Event Appearance Circumstances Time After Death 2–6 hours
Rigor begins Body becomes stiff and stiffness moves down body. *Stiffness begins with the eyelids and jaw muscles after about three hours, *then center of body stiffens, *then arms and legs. (12 hours) 12 hours Rigor complete Peak rigor is exhibited. Entire body is rigid. 15–36 hours Slow loss of rigor Loss of rigor in small muscles first followed by larger muscles. Rigor lost first in head and neck and last in bigger leg muscles. 36–48 hours Rigor totally disappears Muscles become flaccid. Many variables may extend some rigor beyond the normal 36 hours.

Rigor totally disappears
Rigor Mortis Time After Death Event 2–6 hours Rigor begins 12 hours Rigor complete 15–36 hours Slow loss of rigor 36–48 hours Rigor totally disappears

Rigor Mortis Event Time After Death 2 6 8 Face Arms Chest 10 12 Legs
Peak 14 24 Flaccid face Legs start 36 hours Perfect conditions

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?

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

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

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,

2. Livor mortis area of blanching

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.

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.

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.

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

Algor Mortis 3. Algor mortis

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: /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?????

Calculating Rigor: Mathematically Questions: What are some Factors that would affect Algor Mortis?
Ambient temperature Wind? Excess body fat? Clothing etc

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

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

DO NOW: 1. What do you know immediately about a person with a core temp of 24.5oC ? 2. What is the ETOD?

3 Minute DO NOW: 1. What do you know immediately about a person with a core temp of 21.1oC ? 2. What is the ETOD?

Do Now Describe lividity.

Special thanks to

4. Rate of Decay

Describe Putrefaction:

4. Rate of Decay

5. Stomach Contents

Stomach and Intestinal Contents
If undigested stomach contents are present, then death occurred 0 to 2 hours after last meal If the stomach is empty but food is found in the small intestine, then death occurred at least 4-6 hours after last meal If the small intestines is empty and wastes are found in large intestine, then death probably occurred 12 or more hours after last meal

6. Entomology

6. Entimology

Blow Fly Life cycle

Egg Soon after Death—blowfly eggs can be found in the moist, warm areas of a corpse < 8 hrs

Larva Stages 1 (Instar 1) Within 20 hours

Larva 2 (Instar 2) After 2 ½ days

Larva Stage 3 (Instar 3) After 4-5 days

Pre-Pupa After 8-12 days

Pupa After days

Adult After days

Total time 16 to 35

6. Entomology Flies

Total time 16 to 35

6. Entomology Beetles The American carrion beetle, Necrophila americana. Although this beetle is primarily nocturnal, it is commonly observed on the upper surfaces of a body during the daylight hours. Large aggregations of these beetles have been observed, and they can sometimes be as numerous as flies. The sexton beetle, Nicrophorus orbicollis. The sexton beetles are generally nocturnal and are typically found under a body or in the soil immediately surrounding the remains during the daylight hours.

7. Potassium levels in Vitreous humor and clouding cornea

Utility/Applications
Table 1. Types of Analyses That Can Be Performed on Postmortem Vitreous and Their Applications Analysis Utility/Applications Sodium Dehydrations,* water intoxication, low salt pattern, acute ethanol toxicity Potassium PMI, water intoxication, low salt pattern, acute ethanol toxicity Chloride Dehydrations,* water intoxication, low salt pattern, acute ethanol toxicity, vomiting, Glucose Diabetes, nonketotic hyperosmolar coma, DKA Urea (VUN) Dehydrations,† renal failure, uremia, azotemia Creatinine Ketones Fasting/starvation, DKA, alcoholic ketoacidosis, isopropanol ingestion Insulin Insulin overdose C-Peptide Iron Iron overdose/toxicity Alcohols Acute ethanol toxicity, isopropanol ingestion, methanol Drugs‡ Certain drugs can be identified, quantified, and correlated with blood concentrations Antibodies Viral antibodies to HIV and hepatitis B and C in donation cases 6-MAM To distinguish heroin from morphine DNA For purposes of identification Formic Acid Confirm premortem methanol ingestion

7. Potassium levels in Vitreous humor and clouding cornea
Condition Na mmol/L Cl mmol/L K mmol/L Cr mg/dL VUN mg/dL Glucose mg/dL Ketoacids (Pos or Neg) R-OH mg/dL Normal Vitreous < 15 8-20 < 200 Neg Hypernatremic Dehydration >155 >135 Increased >40 Isonatremic Dehydration Hyponatremic Dehydration < 135 < 105 Maybe increased Renal Failure Azotemia, Uremia >150 Low Salt Pattern SIADH Water Intoxication Decomposition < 130 >20 Pos Vomiting Diabetes Mellitus >200 Diabetic Ketoacidosis Nonketotic Hyperosmolar Coma Maybe decreased Alcoholic Ketoacidosis Malnutrition/ Starvation/Fasting Maybe Ethanol ingestion Acute Ethanol Toxicity Binge >350 Isopropanol Ingestion Isopropanol

8. Presence/absence of purge fluid
Decomposition fluid(s) may exude from the oral and nasal passages as well as other body cavities.

9. Stages of Decomposition
Initial decay Corpse appears normal, internal bacterial decay and autolysis begins Putrefaction Odor of decaying corpse swollen Black Putrefaction Very strong odor, flesh appears black, gases escape, corpse collapses Butyric fermentation Cadaver drying out. Some flesh remains at first, and cheesy odor develops. Ventral surface moldy from fermentation Dry Decay Corpse is almost dry, further decay slows from lack of moisture

Stages of Decomposition, through emedicine. Gross after slide twenty
2 days Cells autolysis Greenish purple staining occurs, blood decomposing Skin takes on Marbled Appearance 4 days Skin blisters Abdomen swells with carbon dioxide Due to bacteria in intestines 6-10 days Corpse bloats with CO2 Corpse eventually bursts Fluid begins leaking from openings as cell membranes rupture Eyeballs liquefy Skin sloughs off Adipocere gnaw marks

Guess the Stage of Decomposition

College Forensics Objective: By the end of this activity you will sketch and identify the characteristics of three post mortem intervals. (2, 12, 24, 36 or 48 ) TIMEFRAME: Tuesday 10/20: 1. Select your three Post mortem intervals. Remember that you must complete intervals of 2 and 12 hours. You pick the third. 2. Research the characteristics and events at that timeframe. Wednesday 10/ Pick a character and begin displaying the characteristics. 2. All three on one poster (think how you can do this at the same time???) Thursday 10/ Q+A, discussions in a class setting Friday 10/23: 1. Complete your posters Monday 10/26 Presentations

The Body Farm Freeman Ranch Body Farm, part of Texas State University
University of Tennessee

The Body Farm After only a few weeks in the Tennessee summer, the skull is completely bare and many of the vertebrae are exposed. The rib cage and part of the pelvis are covered with dried, leathery skin.

The Body Farm Close-up of a human femur and hip bone, containing an artificial hip implant. Such orthopedic devices can help identify an unknown crime victim.

Post Mortem 2hr 12hr 24hr 36hr 48hr Rigor Algor Lividity Tache noire Tardieu spots Stomach Contents Entomology Eyes Cloudy Potassium Decomposition Purge Fluids

Chapter 11: Death.

Similar presentations

Presentation on theme: "Chapter 11: Death."— Presentation transcript:

Similar presentations

About project

Feedback

Log in

Auth with social network:

Chapter 11: Death.

Similar presentations

Presentation on theme: "Chapter 11: Death."— Presentation transcript:

Similar presentations

About project

Feedback