Forensic medicine

2. Thanatology
It is a process rather than an event.
clinical death biological death
brain death cellular death
( lack of oxygen)

3. According to registration of births and deaths
act,sec-2(b) defines death as permanent
disappearance of all evidence of life at any time
after live birth has taken place
2 types of death
Somatic death or systemic death
Molecular death

4. It is the complete and irreversible stoppage of the
circulation,respiration and brain functions (bishop’s tripod of
life) but there is no legal definition of death.
It is important in resuscitation and organ transplantation
As long as circulation of oxygenated blood is maintained to the brain stem
,life exists.
Whether the person is alive or dead can only be tested by withdrawal of
artificial maintenance .
 A person who cannot survive upon withdrawal of artificial maintenance is
dead

5. It means the death of cells and tissues individually , which
takes place usually one to two hours after the stoppage of
the vital functions .
Individual cells will live on their residual oxygen for a
variable time after the circulation has stopped , depending
on the metabolic activity of the cell .
Nervous tissues die rapidly,the vital centres of the brain
in about 5 minutes but the muscles live up to one to two
hours
Anoxia

6. •ANOXIA-according to Gordon the stoppage of vitals depend upon
tissue anoxia
•Anoxia : lack of oxygen
•Anoxic anoxia
•Anaemic anoxia
•Stagnant anoxia
•Histotoxic anoxia

7. ANOXIC ANOXIA
In this oxygen cannot reach the blood because of lack
of oxygen in the lung
This occurs from breathing in a contaminated
atmosphere or from mechanical interference with the
passage of air into the respiratory tract.

8. ANAEMIC ANOXIA
In this type oxygen carrying capacity of the blood is
reduced
Like in poisoning by
Carbonmonoxide,nitrates,chlorates,coaltar derivatives
and acute massive haemorrhage,

9. STAGNANT ANOXIA
In this type impaired circulation results in a reduction
of oxygen delivery to the tissues
Eg.Heart failure,embolism and shock

10. HISTOTOXIC ANOXIA
In this type the enzymatic process by which the oxygen
in the blood is used by the tissues are blocked
Eg.acute cyanide poisoning

11. •Normal levels of oxygen in arterial blood is 90-100mmHg
at 30 years and 65-80mmHg at 60 years and above
•Reduction to 60 mmHg results in hypoxia.At
40mmHg,there is severe hypoxia and death may occur at
20 mmHg

12. Historically concept of death was that of “heart and respiration
death”,however have changed this medically in favour of a new
concept “brain death” that is irreversible loss of cerebral function.
It is of 3 types
Cortical/cerebral death
Brain stem death
Whole brain death

13. CORTICAL DEATH
Cerebral death with an intact brain stem.
This produces a vegetative state in which respiration
continues,but there is total loss of power of perception
by the senses.
This state of deep coma can be produced by cerebral
hypoxia, toxic conditions or widespread injury.

14. BRAIN STEM DEATH
Where the cerebrum may be intact,though cut off functionally
by the stem lesion.
The loss of vital centres that control respiration and of the
ascending reticular activating system that sustains
consciousness,cause the victim to be irreversibly comatose and
incapable of spontaneous breathing
This can be produced by raised intracranial pressure,cerebral
oedema,intracranial haemorrhage.

15. WHOLE BRAIN DEATH
Permanent cessation of functions of cerebrum,
cerebellum and brain stem.

16. PHILADELPHIA PROTOCOL
MINNESOTA CRITERIA
HARVARD CRITERIA