Unit 7 Mortality Students will investigate various aspects of death and dying.
Vocabulary • Brain death • Clinical death • Accidental death • Suicidal death • Homicidal death • Natural death • Autopsy • Algor Mortis • Rigor Mortis • Incisions • Lacerations • Abrasions • Punctures • Penetration • Gunshot • Assault • Burns • Taphonomy • Putrification • Black Putrification • Dry decay • Butyric fermentation
Brain Death vs Clinical Death • A. Brain Death • 1. Irreversible end of all brain activity due to total death to the cerebral neurons following loss of blood flow and oxygenation. • 2. The brain is no longer capable of sustaining the rest of the body’s systems. • B. Clinical Death • 1. Cessation of blood circulation (cardiac arrest) and loss of breathing. • 2. CPR may reverse clinical death.
Four different methods of Death • Accidental, Suicidal, Homicidal, Natural • A. Accidental death: Death that happens by chance and was not planned or expected. • B. Suicidal death: The intentional taking of one’s own life. • C. Homicidal death: The act of a human killing another human being. Often called murder. • D. Natural death: Death that occurs from physiological or biological functions. This is the cause of the majority of deaths.
Autopsy Procedure • An autopsy is done by a coroner or pathologist. • It reveals the cause of death, approximate time of death and weapons that were used in the death. • Permission from the next of kin must be obtained when the law does not require an autopsy to be done. • An autopsy procedure: http://video.nationalgeographic.com/video/player/science/health-human-body-sci/human-body/real-csi-sci.html • http://www.nlm.nih.gov/visibleproofs/galleries/media/autopsy/index.html
Steps of an Autopsy • Steps of an autopsy procedure • 1. External examination performed • Photographed from head to toe • All physical characteristics documented • Body measured, weighed and x-rayed. • Fingerprints obtained. • 2. Y-shaped incision made • Deep cut made from the front of each shoulder to the bottom end of the sternum; then to the pubic bone. • Skin peeled back with the top flap placed over the face.
Steps of an Autopsy • Steps of an autopsy procedure • 3. Internal examination • Chest cavity opened with an electric saw. • Ribs are sawn off and the anterior chest wall is cut away to expose the organs that are underneath. • 4. Internal organs removed and weighed • 5. Brain is removed • Skull is cut with an electric saw to create a cap. • Then a transverse incision is made through the brainstem so the brain can be removed.
Steps of an Autopsy • Steps of an autopsy procedure • 6. Intestines are drained • 7. Stomach is opened and drained • 8. Samples are taken from the tissues and organs. • 9. Major blood vessels are cut open and examined. • 10. Internal organs returned to the body and the head and chest are sewn up.
Autopsy of a Fetal Pig • Follow the steps of an autopsy procedure as detailed in your booklet. Do not skip any steps. Read each direction thoroughly.
Determining Cause of Death • Visual examination • Organ examination • Wound/trauma marks analyzed • Toxicology reports (drugs, alcohol, etc – blood work) • Histology reports (slides of tissues – cancer, etc) • Cause of Death vs Manner of Death • What was the body’s physical reason for death (cause). • What caused the physical reason for death (manner)
Jon Benet Ramsey medical report • http://crimeshots.com/AutopsyReport.html
Wound Patterns • A. Mechanical • B. Thermal • C. Chemical • D. Electrical
Wound Patterns • Open Wounds • Incisions • Lacerations • Abrasions • Punctures • Penetration • Gunshot • Assault • Burns
Tool / Weapon Marks • http://www.nlm.nih.gov/visibleproofs/galleries/media/ragsdale/index.html - gunshot study • Tool mark identification powerpoint
Wound Patterns • Closed Wounds • Contusions • Hematomas • Crushing • Chronic • Acute
Algor mortis • The cooling rate of the body after death • As soon as the body dies there is no longer metabolic functions that keep the body at 98.6 degrees F. • The body temperature will begin to even out with the surrounding environment. • Consideration to the type of clothes, the surface area to body mass and surrounding conditions must be evaluated. • Most accurate temperature to determine time of death should be taken within 1-36 hours of death. • The body will cool at a rate of 1-1.5 degrees F per hour until it reaches the environmental temperature.
Livor mortis • Postmortem lividity • The pooling of the blood in the body after the heart stops. • Indicated the position of the body at the time of death. • Begins within a half of an hour following death. • Most evident at approximately 12 hours following death. • After 12 hours the discoloration will not move no matter how the body is disturbed.
Rigor mortis • Rigidity of the skeletal muscles after death. • After death the muscles relax and release ATP as the muscle breaks down making the muscles become rigid. • Begins in the smaller muscles of the jaw, neck and face. • Noticeable stiffness will occur within 3 hours of death. • Rigor mortis is affected by the environmental factors
Taphonomy: AKA Decomp • Taphonomy is science that studies decomposition over time. Stages of decomposition • 1. Fresh stage • a. Occurs in the first few days , 0-3 days • b. Autolysis begins- destruction of cells and organs • c. Algor mortis occurs • d. Attracts insects that begin to lay eggs
Taphonomy: AKA Decomp • 2. Putrefaction stage (days 4-10) • a. Follows the fresh stage until about day 10 post mortem • b. Odor, color change and bloating occur to the body • c. A green color begins in the abdomen and spreads throughout the body because the bacteria within the body is breaking down. • d. Skin in fragile and the body hairs fall off • Black Putrefaction days 10-20
Taphonomy: AKA Decomp • Butyric Fermentation stage • a. Body odor is lost • b. Body begins to dry out and becomes mummified • http://australianmuseum.net.au/image/Butyric-fermentation-20-to-50-days
Taphonomy: AKA Decomp • 5. Dry Decay stage • a. Slow and longest stage of decomposition 50-375 days • b. Body becomes skeletonized: deterioration of the skeletal remains
Decomp in different environments • http://www.bing.com/images/search?q=stage+of+decomposition&form=QBIR&qs=n&sk=&adlt=strict#focal=98d032f10789cec5a0d0de085e6497d3&furl=http%3A%2F%2Fwww.oceanlab.abdn.ac.uk%2Fstaff%2Fmac%2Fmacmarsh.jpg
Insect life cycles (Entomology) • Only certain insects will feed and lay eggs on a dead corpses. Entomologist study the state of development of insects living on a corpse and count back the days to determine time of death. • Most insects follow a sequential life cycle of growth from a fertilized egg to a mature adult. This occurs in four stages.
Adult Greenbottle Fly Adult Hairy Rove Beetle Adult green blow fly Adult Hide Beetle Adult Red-tailed Flesh Fly Adult Bluebottle fly
Adult female blow flies arrive within minutes to lay eggs on a cadaver. Each deposits about 250 eggs in the natural openings of the body and open wounds. The eggs hatch into first-stage maggots within 24 hours. These feed and then molt into second-stage maggots, which feed for several hours, and then molt into third-stage maggots. Masses of third-stage maggots may produce heat, which can raise the temperature around them more than 10° C. After more feeding, the third-stage maggots move away from the body and metamorphize into adult flies.
Stage 1 • Egg: Deposited by female insect within minutes following death in natural openings and open wounds. Contact: Pam Mitchellinfo@BTERFoundation.org949-278-9756BioTherapeutics, Education & Research Foundation
Stage 2 • Larvae: Newly hatched wingless and wormlike form of the insect. Immature stage before metamorphosis occurs. For example a caterpillar, grub or maggot.
Stage 3 • Pupa: Non-feeding stage between larvae and adult. During this stage metamorphosis occurs and the insect hides itself in a cocoon or similar structure.
Stage 4 • Adult: After all changes have occurred and the insect is fully mature.
Environmental factors related to time of death • Temperature of the environment and the season. • Availability of oxygen and air movement. • Surrounding condition and surface the body is resting on. • Humidity • Rainfall • Clothing the person dressing in or wrapped in. • Type of burial. • Access of scavengers and insects to the body. • Person body size and weight • Cause of death. • Any traumatic injuries or wounds
SLIDE SAMPLES OF LIVING AND NECROTIC TISSUE. • Living tissue slide • Necrotic tissue slide
Autopsy • In Utah, autopsies are performed under these circumstances: • Deaths by violence, gunshot, suicide, or accident , except highway accidents. (Utah is unique in the nation in excluding any death resulting or appearing to result from a highway accident from the jurisdiction of the medical examiner or coroner). • 2. Sudden death while in apparent health. (This is defined as any instantaneous death without obvious natural cause, death during or following an unexplained syncope or coma, or death during an acute or unexplained rapidly fatal illness).
3. Unattended deaths. (Unattended means that the person has not been seen by a physician within 30 days of their death. Persons who die while under treatment by prayer or spiritual means in accordance with the tenets and practices of a well-recognized church or religious denomination are not considered to be unattended). • 4. Deaths under suspicious or unusual circumstances • 5. Deaths resulting from poisoning or overdose of drugs.
6. Deaths resulting from disease, injury, toxic effect or unusual exertion incurred within the scope of the decedent's employment. ( However, highway accident deaths while on the job are excluded). • 7. The Medical Examiner may also assist in the identification of a deceased individual. In cases where injury or decomposition make visual identification or fingerprints impossible, the use of dental records may be required. • 8. Deaths resulting from diseases which may constitute a threat to the public health.
9. Deaths due to the Sudden Infant Death Syndrome. • 10. Deaths resulting while the deceased was in prison, jail, in police custody, in the state hospital, or in a detention or medical facility operated for the treatment of the mentally ill or emotionally disturbed or delinquent persons. • 11. Deaths associated with diagnostic and therapeutic procedures.
Section 26-4- 4 (2) states the medical examiner shall have the authority to conduct investigations, perform any necessary examinations, and retain any samples required for the determination of the cause and manner of death or for scientific purposes. The medical examiner may also request any records relating to the medical care and treatment of an individual whose death is under investigation. Failure to provide records is a Class B misdemeanor. • Section 26-4-16 of the law mandates that in any case where the identity of the decedent is known and the legal next-of-kin have requested release of the body, the body must be released within 24 hours after it has arrived at the medical examiner facility. An extension of this time limit may be ordered by a district court. • The records of the medical examiner are considered confidential and may only be released to the legal next-of kin, an authorized investigative agency and/or a physician who has treated the decedent. Any other requests for information must either be authorized by the legal next of kin or by court order. Subpoenas are not considered a valid request for information under the state's confidentiality rules. • Next of kin may obtain a copy of the Medical Examiner's report by submitting a signed letter identifying the deceased and their relationship. The signature on the letter must be notarized. There is no charge for the first copy of a report sent to next of kin. Subsequent copies require payment of a $25 fee.
PERFORM AN AUTOPSY OF A FETAL PIG • Follow the lab instructions. Proper care and procedure are a must!