This document discusses various topics related to forensic medicine including rigor mortis, hypostasis, putrefaction, estimating time of death, causes of sudden cardiac death, respiratory causes of death, gastrointestinal causes, and asphyxial conditions. It provides details on the timing and progression of rigor mortis. It describes the appearance and indicators of hypostasis. It also outlines the stages and signs of putrefaction.

1. Forensic medicine

2. Timing of rigor mortis
 Firstly in small muscle groups
(around the eyes and mouth, the jaw and the
fingers)
 From Head to the legs
 In the face 1-4 hs
 In the limbs 3-6 hs after death
 strength of rigor increasing to a maximum by
approximately 18 hours after death
 Will remain for up to approximately 50 hours after
death

3. Hypostasis
 Aka : livor mortis / postmortem lividity / suggillation
 settling of the blood in the lower (dependent) portion
of the body, causing a purplish red discoloration of
the skin
 Appear 20m-3h after death
 Maximum lividity occurs within 6–12 hours

4. Hypostasis
 The color of hypostasis is variable and may extend
from:
 pink to dark pink to deep purple
 in some congestive hypoxic states, to blue.
 in pressure areas such as the shoulder blades,
buttock & calves discoloration will be pale.
 Some indicators :
 Cherry-pink: CO poisoning
 Dark red: cyanide poisoning
 Bronze: Clostridium perfringes infection.

6. Hypostasis
 Hypostasis is not always seen
 it may be absent in :
the young, the old
anemic
death from severe blood
loss.
 It may be masked :
by dark skin colors
by jaundice
by some dermatological
conditions.

7. Sites of hypostasis
 Depends on the position of the body before death:
 Supine:
 shoulders, buttocks
 heels pressing against surface give white color (pale).
 Vertical (hanging):
 distally in legs & feet.
 Drowning: ‫غرق‬
 chest, upper chest, and upper limbs.
 Face-down death:
 as in epilepsy, drunken victims
 whitening around nose & lips.
 Hypostasis may also occur in viscera:
 Heart: mistaken for MI
 Lungs: mistaken for pneumonia
 Intestine: mistaken for hemorrhagic infarction

8. Hypostasis vs. Bruises
(Ecchymosis)
Hypostasis Bruises
Dependant areas Any where
Well defined edges Ill defined edges
Blood is retained in
intact capillaries
Blood escapes
through ruptured
capillaries
Superficial Deep into skin
Same level on surface Raised
Pale over pressure
areas
Red
Incision: blood flows
from the cut vessel
(washable)
Incision: blood
coagulates in
tissue
No swelling May be with
swelling
With a bruise,
blood will not flow
from the cut

11. 1.Putrefaction
 Start immediately after death at the
cellular level
 Become visible by naked eye at
about 3-4 days
 Its onset depend on several factors
mainly: temperature and humidity
 Two phenomena for putrefaction:
1.autolysis:by digestive enzymes
that released from the
cells
2.bacterial action: most of them
come from the bowel and
clostridium welchii predominates

13.  Start as an area of green discoloration
of the Rt iliac fossa of the ant.
Abdominal wall
 The gut bacteria find their way out the
bowel lumen to the abdominal cavity
and the blood vessels
 As the bacteria spread through the
blood vessels they decompose
hemoglobin
 When present in the superficial vessels
results in linear branching patterns of
variable discoloration of the skin called
“marbling”.
 Prostate and uterus are relatively
resistant to putrefaction

14. Estimating the time of death
1.Body temperature :
the best and the most commonly
used
Rectally using long, low-reading
thermometer
2.Rigor mortis
3.Hypostasis:
complete after 6 hrs
4.Biochemical investigation of the CSF:
requires the determination of the
amino acid content & lactic
acid & non-protein nitrogen

15. 5.Eye pressure:
eye balls become softer, and less
fluid pressure in the first 3 hrs
6.Gastric emptying:
depend on type of meal and
emotional status.
7.The entomology of dead:
Studying insects & their maggots
which infest the dead body for
estimating the probable time of death.
Different types of insects infest the
dead body at different stages after
death occurs.

16. Disease of the heart :
Δ Coronary artery disease
1-Coronary atherosclerosis:
-The most common cause of sudden death .
-Mostly affects :
* Left Anterior Descending Artery (LADA)
*Right Coronary Artery (RCA)
*Left Common Carotid Artery (LCCA)

17. Complications of coronary
Atherosclerosis :
1-rupture of ulcer atheromatous plaque .
2-sub-intimal hemorrhage .
3-Thrombosis  most common
4-aneurysm
5-Ischemia
6-Infarction
7-Peripheral Vascular Diseases

18. Δ Coronary artery disease ,Cont:
2- Myocardial Infarction :
- Myocardial infarction occurs when there is severe stenosis - 75%
or more of the lumen of a major branch - or complete occlusion
of a coronary artery . but death can be attributed to coronary
artery disease (CAD) with less stenosis if other signs of chronic
myocardial ischemia are apparent (left ventricular
hypertrophy [LVH], fibrosis, previous infarct).

19. Complications of MI :
1-Rupture of myocardial infarct :
The area of the myocardial infarct is weakest between 3 days
and 1 week after the clinical onset of the infarct and it is
at this time that the weakened area of myocardium may
rupture, leading to sudden death from :
*haemopericardium
*cardiac tamponade

20. 2-Cardiac Aneurysm :
- One week post MI .
- may form at sites of infarction; they may calcify
and they may rupture.

21. Δ Cardiomyopathies :
 HCM (hypertrophic cardiomyopathy):
-inherited (AD)or sporadic
-leading cause of sudden cardiac death in
young athletes
-decreased compliance and death due to diastolic
dysfunction.
-sudden death may be the first manifistation.
 RCM (restrictive cardiomyopathy ):
-causes . -enlarged atria and small thin ventricles
. –death also due to diastoloic dysfunction

22. Functional abnormalities
Pathologically, there are no ‘naked eye’ or microscopic
abnormalities in the heart as the defects are at a
molecular level.
 Long QT syndrome (LQTS).
 short QT syndrome (SQTS).
 Brugada syndrome ( It is the major cause of
sudden unexplained syndrom (SUDS) in young men)

23.  Dissecting aortic aneurysm
(90% occur in the ascending aorta either just distal to
the aortic valve or the left subclavian artery)
Dissecting aneurysms are principally found in
individuals with hypertension, but may also be seen
in younger individuals with connective tissue defects,
such as Marfan syndrome

24. Rupture of berry aneurysm
Any rise in the blood pressure will cause rupture of the apex
of the aneurysm/ one of the most common causes of
death inyoung to middle-aged adults, if coronary
disease is excluded.

25. Asthmatic
patients
Pulmonary
embolism
massive
hemopt
ysis
Pneumo
nia

26. Respiratory causes :
1-Asthmatic patients : may die suddenly and
unexpectedly, without necessarily being in status
asthmaticus or even in an acute asthmatic attack.
May be due to Hypoxia and respiratory acidosis. autopsy
little or nothing is found, except confirmation of the
chronic asthmatic state.
2-Pulmonary embolism (most common cause of death
in pregnancy) :
In almost every case, the source of the emboli is in the
leg veins and pelvic veins. After any tissue trauma, or
even surgical operation, especially where immobility or
bed rest occurs, deep vein thrombosis develops.
3-massive hemoptysis from cavitating pulmonary
tuberculosis or from a malignant tumor
4-pneumonia

27. Fatal
abdominal
catastrophes
Esophageal
varices
Perforation
of a peptic
ulcer
GI
Causes
Mesenteric
thrombosis and
infarction ,
Strangulated
intestine
: It is often difficult to identify
the varices at autopsy, as they have
collapsed

28. Genitourinary system
If a woman in child-bearing age is found unexpectedly death,
complications of pregnancy must be considered like :
Induced abortions
Amniotic fluid emblosim
Ruptured Uterus
ruptured ectopic gestation.

29. Autopsy-negative causes of
death
Every cause of death we’ve mentioned so far will have
A positive finding manifested during autopsy , now what if
there were NO PSTIVE FINDINGS ?
Then we will probably be left with what we call

30. Endocrinopathies ( DKA , thyrotoxicosis ..).
Electrolyte abnormalities.
Other:malignant syndrome,Cardiac
dysrhythmia,anaphylaxis
Autopsy-negative causes of death

31. A-External examination
 Signs of malnutrition or dehydration .
 Supraclavicular congestion in sudden cardiac
death.
 fingernail clubbing in chronic heart disease.
 Splinter hemorrhage in infective endocarditis.
 Signs of trauma, such as manual strangulation or
low-voltage electrocution.

32. B-General internal examination
 Organs should be examined in situ before
manipulation
 fluid within any body cavity should be measured
(volume) and described (serous, serosanguineous,
purulent, chylous, frank blood)
 The lungs should be examined for evidence of
hyperinflation (asthma, emphysema aquosum)
 Evisceration should be performed, or directly
observed, by the pathologist
 Evaluations for tension pneumothorax should be
done before the thoracic cavity is entered
 Internal examination of body systems most often
implicated in sudden death ( CVS , RS ,CNS , GIS)

33. Sudden infant death syndrome(SIDS)
 Crib death, syndrome in which healthy infants(1 month to a
year) die from unknown causes (usually during sleep).
 Most deaths due to SIDS occur between 2 and 4 months of age,
and incidence increases during cold weather.
 More boys than girls fall victim to SIDS..

34. What are the risk factors for SIDS ?
 Smoking, drinking, or drug use during pregnancy.
 Poor prenatal care.
 Poor prenatal nutrition.
 Prematurity or low birth-weight.
 No breast feeding.
 Mothers younger than 20.
 Smoke exposure following birth.
 Overheating from excessive sleepwear and bedding.
 Stomach sleeping.

35.  Lethal Dose ( LD50 ) : the dose at which 50% of which who
took the dose will die

36. SPECTRUM OF ALCOHOL USE / ABUSE
 Social drinker - drinks occasionally (not frequent)
 Heavy drinker - drinks regularly and heavily (Men >7
units/day, Women >5 units/day).
 Binge drinker - drinks irregularly and heavily.

37. Alcohol
Absorption
*completed 1-3
hrs
20 %
Stomach
80%
Upper Small
Intestine

38. Increase
Absorption
• Empty Stomach
• Gasterectomy
• 10 – 20% concentration
is the optimum
Decrease
Absorption
• Food in Stomach
• Higher Concentration of
Alcohol

39.  Physical clues are blood-shot eyes, dilated pupils,
rapid bounding pulse, physical inco-ordination and
nystagmus (jerking eye movements) on lateral gaze

40. More about alcohol effect
Skin =vasodilation and hypothermia
Respiratory=aspiration pnemonia
Blood=anemia and leukopenia
GIT=liver cirrhosis, pancreatitis, gastritis, peptic
Ulcer, portal varices
Reproductive:
=Irregular period ,breast & genital atrophy
=loss of libido ,decrease sperm count, testicular
atrophy
Pregnancy=spontaneous abortion ,fetal alcoholic
syndrome ,delayed mental and motor
development in child lactating from alcoholic
mom,

41. CAUSES OF DEATH IN CHRONIC ALCOHOLICS
 1. Trauma. The largest group (26%).
Fire deaths were the most common. Drunken falls were frequently
followed by fatal head injury. Murder, Road traffic accidents
(pedestrians),Drowning, Accidental poisonings.
 2. Incidental Natural Disease (25%). Ischemic heart disease,
cerebral hemorrhage, chronic obstructive airways disease and
malignancy.
 3. Alcohol Related Disease (22%). Bronchopneumonia and
lobar pneumonia are the commonest. Cirrhosis of the liver due to
ruptured varices or hepatic failure. Many of these deaths occur in
hospital and are excluded from forensic practice. Alcoholic
cardiomyopathy and pancreatitis are other rarely reported causes
of death.
 4. Acute Intoxication (24%).
Possible mechanisms of death from simple intoxication:
1. Simple depression of the respiratory centre in lower brain stem
by alcohol itself.
2. Inhalation of vomit due to coma.
3. Postural asphyxia (obstruction of the upper airway by the
swallowed tongue during coma.
 5.'Obscure' cause of Death is noted in a variable proportion of

42. Asphyxial Conditions

43. Phases of Asphyxia
 1- Forced respiration:
 Due to Stimulation of respiratory center
 Clinical Picture: Dyspnea.
 2- Stage of convulsions:
 It is due to cerebral irritation
 Clinical Picture:
Convulsions, cyanosis, Hypertension, loss of consciousness,
constricted pupil.
• 3- Paralysis:
 Clinical Picture:
loss of consciousness, flaccid muscles & lost reflexes, deep
cyanosis, dilated pupils, irregular breathing.
 Death occur after 5 minutes

44. Classical Signs of Asphyxia
 Petechial hemorrhages in the skin of the face and in
the lining of the eyelids.
 In the viscera, they are called Tardieu spots.
 Congestion & edema of the face.
 Cyanosis (blue discoloration) of the skin of the face.
 Right heart congestion and abnormal fluidity of the
blood.

46. Petechial Hemorrhages

47. Tardieu Spots

48. Survivors of Asphyxial Episodes suffer
from:
 Pain and tenderness around the neck.
 Damage to the larynx and hyoid bone.
 Dried saliva around the mouth.
 Cyanosis, congestion, edema and petechiae of the
structures above the level of compression.
 Hemorrhage from the mouth, nose and ears.
 Incontinence of feces and urine.

49. Strangulation
Manual Strangulation
 Throttling.
 The application of
pressure to the neck
using the hands.
 Seen usually in
Homicides.
 Bruises and abrasions
in the front of the neck
and lower jaw.
Ligature strangulation
 May be homicidal,
suicidal or accidental.
 Involves the application
of pressure to the neck
by an item capable of
constricting the neck,
such as a scarf, neck-
tie, stocking or
telephone cable…etc.
 Ligature mark.

50. Hanging
 Suspension of the body by the neck.
 Ligature mark (V shaped) with discontinuity at
suspension point.
discontinuity at suspension point

51. Compressional and Positional
Asphyxia
 Pressure on the trunk
(chest and/or abdomen)
can result in an inability
to breathe effectively
and result in death.
 Traumatic, and crush
asphyxia.
 Persons with impaired
neurological function
are more susceptible.

52. Smothering
 The physical occlusion of the nose and mouth resulting in
asphyxia.
 May leave no ‘asphyxial signs’ in survivors or the
deceased.
 If the individuals are unable to struggle, owing to extremes
of age or intoxication, for example, they may have no
evidence of injury, including around the mouth or nose.
 Occasionally, examination will reveal intraoral injury
(including bruising or laceration of the insides of the lips or
bruising of the gums in an edentulous individual) and soft
tissue dissection of the face may reveal subcutaneous
bruising around the mouth and nose.

53. Smothering

54. Autoerotic Asphyxia
 Autoerotic asphyxia is the term used to describe
those fatalities occurring during some form of
solitary sexual activity.
 Sexual asphyxia, sex hanging, asphyxiophilia,
Kotzwarrism, autoasphyxiophilia and
hypoxyphilia.
 The recurrent feature tends to be the use of a
device, appliance or restraint that causes neck
compression, leading to cerebral hypoxia, with
the aim of heightening the sexual response.