Death & PM changes

Question 1

Stages of death

Answer 1

1- somatic (Clinical) death

2- Molecular (cellular) death.

Question 2

Somatic (clinical) death

Answer 2

COMPLETE And IRREVERSIBLE cessation of vital functions of the (Brain, Heart, Lungs).

Question 3

Molecular (cellular) death

Answer 3

Death of individual ORPHANS and TISSUES due to cessation of circulation.

Question 4

What is molecular life

Answer 4

It is the period BETWEEN (somatic and molecular death), although life ceases in the body as a whole, it persists in its components (tissue and cells respond to physical, chemical, or thermal stimuli).

Question 5

Duration of the molecular life

Answer 5

Depends upon O2 requirement.
Most sensitive: nerve cells (die within few minutes).
Least sensitive: connective tissue cells (die within hours).

Question 6

Characteristics of molecular life

Answer 6

• muscle contraction on electric excitation.
• ciliary muscle reaction to atropine by pupil dilatation and physostigmine by its contraction.
• motile sperms maybe found at GU system for few hours after death.

Question 7

Diagnosis of death

Answer 7

1- immediate signs (6).
(Arrest of circulation- arrest of respiration- arrest of brain function) very imp
( 1ry flaccidity and contact flattening- ocular signs- skin changes).
2- early signs (3). Very imp [first 24 hours].
-cooling -Hypostasis -rigor mortis.
3- delayed signs (4) [ >24 hours]
-putrefaction - mummification -adipocere formation -maceration.

Question 8

MLI of molecular life

Answer 8

Organ transplantation: carried out only during period of molecular life.

Question 9

Arrest of circulation diagnosed by

Answer 9

• no peripheral Pulse (not reliable).
• no beat in auscultation on the 5th intercostal space for 5 minutes. (More reliable than pulse but could be difficult in some cases).
• flat ECG for 5 minutes.(imp)

Question 10

Arrest of respiration diagnosed by

Answer 10

(Must be COMPLETE and CONTINUOUS)
By
-Inspection (chest wall).
-Auscultation for 5 minutes better in the LARYNX.

Question 11

Define Brain death

Answer 11

PERMANENT absence of all brain function including of the brain stem.

Question 12

Types of brain death

Answer 12

• Cortical death (with intact brain stem so, spontaneous respiration and intact cardiac function).
• Brain stem death (with intact cortex is RARE).
• Whole brain death (cessation of all brain function).

Question 13

Characteristics of Cortical death

Answer 13

• Victim exist in vegetative state.

- Not considered dead.

Question 13

What is (PVS) persistence vegetative state

Answer 13

-is A clinical condition due to cortical death characterized by
complete unawareness of self and environment results from
traumatic and non-traumatic injuries (hypoxia).

Question 14

MLI of brain death

Answer 14

• To take decision of termination of Life support systems.

- Organ transplantation (only when permanent brain death surely established.

Question 15

Before diagnosing Brain death

Answer 15

Before u have to exclude 3 possibility:

• Intoxication (sedative, hypnotics, neuromuscular agents
• metabolic and endocrine disturbances as a cause of coma.
• Hypothermia as a cause of coma (central body temp should be >35).

Question 16

Brain death diagnosed by

Answer 16

1- By Ex:
Sx of cortical death:
No wakefulness and awareness 
No gag ,corneal, light reflexes.
Sx of brain stem death:
Loss spontaneous breathing (APNEA TEST)
2- By EEG (not reliable) depends on cortical electricity.
3- By cerebral blood flow (CBF):
Doppler, scintigraphy, angiography.

Question 17

What is 1ry flaccidity

Answer 17

Complete relaxation and loss of both TONE and REFLEXES of VOLUNTARY and INVOLUNTARY muscles.
The duration is: about (3 hours) after clinical death
In this stage muscles: still react to external stimuli (molecular life).

Question 18

What is contact flattening

Answer 18

Flattening of the convex parts of the muscles compressed against flat surfaces

Question 19

Ocular Sx

Answer 19

-Sclera “taches noires de la sclérotique”
(Due to exposed to debris, dusts and evaporation).
-Cornea (cloudy opaque dry).
-IOP decrease rapidly
Drops its half at the time of death
And become nil by 2 hours.(imp)
-Retina 1- TRUCKING inside b.v within 15 minutes. 2- pale optic disc

Question 20

What are the PM Skin changes

Answer 20

• Pale skin.
• Loss its elasticity > no gaping of the wound.
• loss its translucency due to no circulation

Question 21

Early Sx

1- what is Cooling

Answer 21

No heat production
+ continue loosing heat
1-1.5 C*/hour Till reach atmospheric temp in about 18 hours
(heat loss occurs by Conduction, Convection and Radiation).

Question 22

Site of measuring temp in Cooling

Answer 22

Sites of measure:

• Rectal using (Chemical thermometer)
• Cut Under surface of liver (visceral temp) using (digital probe)

Question 23

MLI of Cooling

Answer 23

1-Time 
2-Cause 
*severe hemorrhage > rapid cooling.
*(P.M. Caloricity): body heat retained or even increase [4S] 
-sunstroke. -Strychnine and tetanus.
-Sepsis. -Severe asphyxia.
3-Differ between 1ry and 2ry flaccidity.

Question 24

2- Hypostasis

Answer 24

Bluish purple discoloration of most defendant parts of body (EXTERNALLY and INTERNALLY) due to gravity of blood inside b.v. Time of onset: [ 1 - 3 - 8 ] 1- small separate patches 3- coalesce together 8- complete and fixed

Question 25

MLI of Hypostasis

Answer 25

``` 1-SURE Sx of death 2-Time 3-Position 4-Cause: (by site and color of Hypostasis) Pale > severe anemia and hemorrhage Dark > reduce Hb Red asphyxia > CO, cold and cyanide Brown > met Hb (nitrate poison). ```

Question 26

3- Rigor Mortis def ?

Answer 26

Progressive rigidity of VOLUNTARY and INVOLUNTARY muscles. | Decrease ATP > actin-myosin fuses and form (dehydrated stiff gel).

Question 27

Timing of rigor mortis

Answer 27

Time: 2 - 12 - 18 - 36 2: starts in small muscles of face 12: whole body 18: disappear from small muscles 36: disappear from whole body and become 2ry flaccidity.

Question 29

MLI of Rigor Mortis

Answer 29

1- SURE Sx of death. 2- Time (PMI). 3- Position: depend about excessive ATP use e.g. Footballer 4- Cause: Rapid and transient in case of Convulsions, electrocution, violence, septicemia or Strychnine.

Question 30

What is 2ry Flaccidity

Answer 30

Muscles become flaccid again but do not respond to stimuli. | This stage synchronous with the onset of putrefaction

Question 31

Differences between 1ry and 2ry Flaccidity

Answer 31

1ry: - At moment of death. - Loss of tone. - Respond to stimuli. - Warm body temp. 2ry: - after Rigor mortis. - due to AUTOLYSIS - No response. - Much lowered body temp.

Question 32

Delayed signs of Death

Answer 32

``` 1-Putrefaction. 2-post mortem conditions replacing putrefaction: A-Mummification. B-Adipocere. C-Maceration. ```

Question 33

Def of Putrefaction

Answer 33

Process of decomposition of tissue > resolution of body from organic to inorganic state.

Question 34

Mechanisms of putrefaction

Answer 34

1-AUTOLYSIS by tissue enzymes. | 2-BACTERIAL action by enzymes and produce gases.

Question 35

MLI of putrefaction

Answer 35

1-SURE Sx of death. 2-TIME of death. 3-CAUSE of death.

Question 36

Time of Putrefaction | 2days winter , 1day summer

Answer 36

- greenish Rt iliac region (cecum full of bacteria and fluids). - ARBORISATION (marbling) means distended green veins.

Question 37

Time of Putrefaction | 1week winter ,3-4days summer

Answer 37

- spread of GREENISH over whole body. - Distended abdomen and ext genitalia. - FROTH from mouth and nostrils. - swelling face protruding eye and tongue.

Question 38

Time of Putrefaction | (2weeks winter , 1week summer){ ٣ب}

Answer 38

- Pealing of skin falling of hair and nail. - Bursting of abdomen. - Body orifices filled with larva (worms).

Question 39

Time of Putrefaction | 6 months

Answer 39

All soft tissue liquified, only bones ATTACHED by ligaments.

Question 40

Time of Putrefaction | 12 months

Answer 40

Separate bones which become (lighter, whiter, brittle and less smelly)

Question 41

Rapid putrefaction due to

Answer 41

- SEPTICEMIA. | - EDEMA and ASCITES (CHF, hepatic failure).

Question 42

Slow putrefaction due to

Answer 42

- HEMORRHAGE. | - METALLIC POISON as arsenic > (dehydration and bactericidal).

Question 43

Deferences between putrefaction froth and froth from foam

Answer 43

Putrefaction froth : | •Coarse. •Bloody. •Foul smell. •

Question 44

Difference between blisters of putrefaction and burns

Answer 44

Putrefactive blisters: | Mainly gas little reddish with no vital reaction.

Question 45

جدول ال | Mummification, adipocere and maceration

Answer 45

Mummification: EVAPORATED fluid. Adipocere: unsaturated F.A > hydrogenated > SATURATED F.A. Maceration: ASEPTIC AUTOLYSIS.