FSE2100 Chapter 5
Post Mortem Changes - Chemical Changes
Change in body pH
Post Mortem Changes - Physical
Dehydration - the loss of water from body tissues and fluids by surface evaporation.
Post Mortem Changes - Physical
Dessication - this is the complete removal of moisture. This does not happen very often in the United States, as you must be in an area with NO humidity. Dessication is part of the process of mummification.
Antemortem Changes - Gases in tissue
During life, the person may obtain Gas gangrene (In dead bodies, this disease is called Tissue Gas.)
Moribund (literally Mortality Bound)
Dying. At the point of death
Post Mortem Changes - Physical
Endogenous invasion of Microorganisms
Post Mortem Changes - Physical
Hypostasis - process by which blood settles, as a result of gravitational movement within the vessels, to the dependent, or lower parts of the body.
Post Mortem Changes - Physical
Increase viscosity of blood
Post Mortem Changes - Physical
Livor Mortis - the settling of blood brings about a discoloration that appears within 1.5 to 2 hours after death. Liver mortis is a postmortem intravascular blood discoloration that occurs as a result of hypostasis.
Post Mortem Changes - Chemical Changes
Post Mortem Caloricity - rise in body temperature after death due to continued cellular metabolism.
Post Mortem Changes - Chemical Changes
Post Mortem Stain - extravascular color change that occurs when heme, released by hemolysis of red blood cells, seeps through the vessel walls and into the body tissues.
Agonal hypostasis
The settling of blood into the dependent tissues of the body. Occurs as a result of the slowing of circulation just prior to death, which allows the force of gravity to overcome the force of circulation.
Antemortem Changes - Therapeutic changes
There are a variety of changes that can occur due to the condition and treatment of the body such as: 1. blood thinner may have been used 2. antibiotics may be in the system 3. chemotherapy may be been employed 4. vasodilators may have been used to dilate the vessels to allow more blood to flow through the system 5. anti-inflammatory agents may have been used
Catalepsy
a medical condition characterized by a trance or seizure with a loss of sensation and consciousness accompanied by rigidity of the body.
Agonal translocation
an agonal or postmortem redistribution of host microflora on a hostwide basis.
Agonal coagulation
(Congealing) - in reference to blood, a change from a fluid into a thickened mass.
Articulo Mortis
at the point or moment of death
Human Remains
body of a deceased person, including cremated remains. the body in whole or in part
Apparent Death
condition in which the manifestations of life are feebly maintained.
Agonal edema
escape of blood serum from an intravascular to an extravascular location immediately before death.
Cremated Remains
human remains which have been cremated
Agonal fever
increase in body temperature immediately before death
Mortality Rate
is a measure of the number of deaths (in general, or due to a specific cause) in a particular population, scaled to the size of that population, per unit of time
Extrinsic factors effecting decomposition
outside temperature, humidity, air, bacteria, pressure due to earth or clothing, and vermin (maggots, lice, and rats)
Agonal
pertaining to death or extreme suffering.
Cadaveric spasm a.k.a. Instantaneous Rigor
prolongation of the last violent contraction of the muscles into the rigidity of death.
Hydrolysis
reaction in which water is one of the reactants and compounds are often broken down. In the hydrolysis of proteins, the addition of water accompanied by action of enzymes results in the breakdown of protein into amino acids.
Autolysis (by lysosymes)
self-destruction of cells; decomposition of all tissues by enzymes of their own formation without microbial assistance.
Death struggle a.k.a. Death Throw
semi-convulsive twitches that often occur before death.
Corpse
the legal term for a dead body
Cadaver
the medical term for a dead body
Fermentation
the microbial (enzymatic) decomposition of carbohydrates under anaerobic conditions.
Suspended animation
this is sometimes referred to as "out-of-body experiences"
Order of decomposition of organic compounds
1) carbohydrates 2) proteins 3) lipids 4) bones
Order of Decomposition of organs of the body
1) lining of larynx and trachea 2) stomach 3) intestines 4) spleen 5) liver 6) adult brain 7) heart 8) lungs 9) kidneys 10) non-pregnant uterus Exceptions to the list 11) the infant brain decomposes more rapidly than any other organ. 12) the pregnant uterus decomposes more rapidly than other organs. i. End results 1) amines 2) fatty acids 3) Ptomaines a) cadaverine b) putrescine
Order of decomposition of tissues
1) liquid tissue - blood and lymph 2) soft tissue - linings of organs 3) firm tissue - muscle and muscle of organs 4) hard tissue - cartilage and bone
Agonal & Post Mortem Period
1. Agonal Period - period immediately before somatic death. 2. Somatic Death - death of the organism as a whole. These stages are in order of occurrence. a. Clinical Death a.k.a. Legal Death - during this time period CPR sometimes brings a person back to life b. Brain death - during this time period medical intervention sometimes brings a person back to life. The intervention must be more than CPR c. Biological death - The person is irreversibly dead. d. PostMortem Cellular Death - Prior to this time, organs and tissue may be harvested from the body for medical donation. If the cells died at the same time as somatic death, we could never have organ donors for hearts, lungs, corneas, etc.
Signs of Death
1. cessation of respiration 2. cessation of circulation. 3. muscular flaccidity 4. changes in the eye, including; clouding of the cornea; loss of luster of the conjunctiva; flattening of the eyeball; dilated and unresponsive pupils. 5. postmortem lividity. 6. rigor mortis. 7. algor mortis. 8. decomposition.
5 Cardinal Signs of Decomposition
1. color change 2. odor 3. skin slip ( desquamation ) 4. gases 5. purge
Uniform Determination of Death Act
A. This act defines how to determine when death has occurred and says the following: An individual who has sustained either: 1. irreversible cessation of the circulatory and respiratory systems OR 2. irreversible cessation of all functions of the entire brain and the nervous system, is dead. B. This act involves all three organs in the Tripod of Life To live we need all three of these organs functioning properly. 1. Brain a. coma - if death begins with the brain it is usually through a condition known as a coma 2. Heart a. syncope - if death begins with the heart it is usually through a condition known as a syncope 3. Lungs a. asphyxia - if death begins with the lungs it is usually through a condition known as asphyxia.
Post Mortem Changes - Physical
Algor Mortis - postmortem cooling of the body.
Antemortem Period
Ante means "before" & Mortem Means "death" 1. Necrobiosis - antemortem, physiological death of the cells of the body followed by their replacement. 2. Necrosis - pathological death of a tissue still a part of the living organism.
Putrefaction occurs more slowly for a body immersed in water than for a body in air.
First sign of decomposition will be in the fact and neck for the body in water.
Post Mortem Changes - Chemical Changes
Rigor Mortis: postmortem stiffening of the body muscles by natural body processes. a. Stages of Rigor mortis 1) primary flaccidity 2) rigor mortis 3) secondary flaccidity b. Order of appearance 1) eyes 2) face 3) neck 4) arms 5) torso 6) legs c. time of appearance and disappearance 1) Though the book says appearance can occur at 2 -4 hours, it is usually closer to 6 - 10 hours 2) rigor usually lasts 10 to 72 hours. d. Burned (scalded bodies) do not exhibit rigor e. Conditions mistaken for rigor mortis 1) catalepsy 2) cold stiffening - when placed in refrigeration 3) heat stiffening 4) Cadaveric Spasm f. factors that effect rigor mortis 1) age a feeble and short rigor mortis is usually seen in infants and elderly persons 2) muscular development The more muscular a person is, the more quickly rigor mortis will occur and the longer it will last. Additionally, the rigor mortis will be much stronger than that of non-muscular individuals. If the deceased were an avid body-builder, rigor may appear in 2 to 4 hours and last 3 days. 3) temperature of the environment rigor mortis is accelerated by heat and retarded by cold 4) Cause of death Exhausting diseases accelerate rigor mortis, while sudden death of a previously healthy individual will produce a very pronounced state of rigor mortis. 5) Gender Typically men have more muscle mass, will typically have a stronger and longer lasting rigor. g. Methods to reduce rigor Rigor mortis is very similar to stiff muscles that one gets during life. The best way to releave the stiffness is to move, flex, extend, rotate, and massage the muscle. The same is true for reducing rigor mortis.
Tests for Death - Expert Tests
a. Stethoscope - to listen to chest b. Ophthamoscope - to look in the eyes c. Electrocardiogram (ECG or EKG) d. Electroecephalogram (EEG) c & d are the heart and brain monitors in the hospital e. Dye injection - In this test, the physician would inject dye into a blood vessel. If the dye did not spread through the vessel, it meant the blood was not moving and therefore the person was dead. If the dye did begin to spread through the vessel, I can only guess that the dye in the vessel, served as a poison and instantly killed the person.
Tests for Death - Inexpert
a. feel for pulse b. mirror test Place a mirror under the nose of the deceased, adn hold it there for a period of time. If they are alive, they will fog up the mirror. If they are dead, the mirror probably will not fog up. c. ligature test d. ammonia injection test
Intrinsic factors effecting decomposition
age, gender, corpulence, cause and manner of death, indigenous flora (microorganisms), febrile conditions, and pharmaceutical drugs taken prior to death
Somatic Death
death of the organism as a whole.
Lipolysis
decomposition of fats.
Decay (by aerobes)
decomposition of proteins by enzymes of aerobic bacteria.
Putrefaction (by anaerobes)
decomposition of proteins by the action of enzymes from anaerobic bacteria.
Proteolysis
decomposition of proteins.
Saccharolysis
decomposition of sugars
Agonal algor
decrease in body temperature immediately before death
Hemolysis
destruction of red blood cells that liberates hemoglobin
Morbidity Rate
looks at the incidence of a disease across a population and/or geographic location during a single year.
Agonal dehydration
loss of moisture from the living body during the agonal state.
Antemortem Changes - Translocation
movement of microorganisms from one area of the body to another. occurs as organisms normally confined to a specific area of the body by natural body defenses are able to move as the body loses its ability to keep them in check.
Death Rattle
noise made by a moribund person caused by air passing through a residue of mucous in the trachea and posterior oral cavity.
Agonal capillary expansion
opening of the pores in the walls of the capillaries. occurs as the body attempts to get more oxygen to the tissues and the cells.
