Re: Why can't a dead person come back to life if they are given new organs?

With as simple as your question sounds, it is a difficult one to answer.  
Without knowing how an individual died and a variety of health and 
biological information about the individual, it is difficult to say whether 
or not a person can be brought back or resuscitated.  To start off, there 
are basically two accepted "deaths" an individual can be declared: natural 
and clinical.   "Natural" death basically means an individual's body just 
can't function any more.  It also means that medicine has done all it can 
and it can not bring a person back.  With a natural death there are often 
several inter-relating diseases, illnesses, or problems that contribute to 
an individual's death.  When an individual has more than one medical 
problem, it is often very difficult to overcome all the different problems 
in order to bring them back.  This is one of the "that's just the way it 
is" type of situations - the body just can't go one no matter how hard we 
try. 

However, in the second case of an individual being declared "clinically" 
dead, it is possible to bring a person back.  Technically, this means that 
an individual's heart and lungs have stopped and their pupils do not 
contract when light is shined into them. Some practitioners, however, 
believe an individual is not truly dead until all brain activity ceases - 
which of course then would cause the heart and the rest of the body to also 
stop. The most promising clinical death where an individual might be 
resuscitated is when the heart is stopped without much damage to the rest 
of the body.  There have been many documented cases in which individuals 
are declared "clinically" dead and have been brought back.  These include 
victims of drowning, heart attacks, electric shock, individuals trapped in 
icy conditions, etc.  The following article describes how an individual was 
resuscitated after being trapped in an icy river for an hour and declared 
clinically dead:  http://news.bbc.co.uk/hi/english/health/newsid_620000/620609.stm

The question on whether or not an individual can be resuscitated after 
"dying" is basically a matter of the individual's overall health, current 
bodily functions, and bodily damage while the individual is considered 
"dead".  When your heart and lungs stop working, your blood quits flowing.  
And when your blood quits flowing, oxygen is no longer being delivered to 
the many tissues and organs in your body and then they start to die.  Your 
cells need to oxygen in order to function.  This is why it is quite 
important to keep breathing and have a heart beat.  Without a constant 
supply of oxygen, tissues and organs become damaged and may not recover, 
even if you were to get your heart and lungs started again.  It is said 
that the brain has about 7 minutes after the heart stops before it starts 
to suffer damage due to the lack of oxygen.  Once the body has reached a 
certain amount of damage, it is difficult to get the much needed bodily 
functions to perform as they should and quickly becomes one of "that's just 
the way it is" type of situations.

However, one interesting phenomena that has helped individuals recover from 
extended periods of clinical death is the slowing of cell activity through 
hypothermia.  As noted in the article mentioned above, hypothermia is when 
the body is chilled below the normal body temperature of 37 degrees Celcius 
(98.6 degrees Fahrenheit).  This typically means a core body temperature of 
less than 35 degrees Celcius (95 degrees Fahrenheit) - which is considered 
the clinical state when the body is unable to generate sufficient heat to 
efficiently maintain functions.  This scientific and medical find has 
allowed many more individuals to be resuscitated and help organ transplants 
occur more successfully.  For use in organ transplants, the body is 
significantly chilled to slow all bodily functions, to the point of 
stopping the heart, the medical procedure occurs, and then the body is 
warmed back up with hopes of recovery.  By chilling the body, the rate at 
which the body's cells die is reduced plus less blood is lost during the 
medical procedure.  In fact this procedure is gaining use in various types 
of critical transplants, namely heart transplants.  The Heart Center Online 
has several articles on how a heart transplant is performed which can be 
located at:  http://www.heartcenteronline.com/myheartdr/home/index.cfm

Organ and tissue transplants have come a long way in recent years.  It is 
now quite common for them to occur.  There are heart transplants, lung 
transplants, cornea transplants, liver and skin...... and the list could go 
on.  The unfortunate thing is that the supply of donor organs and tissues 
is low and finding a match that the receiving individual's body will not 
reject is difficult.  Therefore, even if an individual just needs a new 
heart or liver, it may not be compatible to the individual or one is just 
not available.

So to basically answer your question, there are situations where an 
individual can literally be brought back from the dead.  It's all a matter 
of oxygen supply to the body's cells and the overall health of the 
individual - whether or not there are other complications (illnesses, 
disease, etc) that keep the body from resuscitating or recovering.  The 
fact that an individual is healthy but may have a bad organ may mean that 
they may be able to survive longer with a compatible new organ.  But keep 
in mind, often times there are inter-related health problems that may not 
be identified until the last minute plus surgical and biological 
complications that still may cause an individual to die, despite all the 
medical and scientific help and assistance we can offer them.  As medicine 
and science advance, there will always be new ways to help individuals 
recover; however, if the body is weak and sufficiently damaged, no medical 
advances can bring an individual back.

Two additional references on the web about cell biology and organ 
transplants that may help answer your question are: http://vlib.org/Science/Cell_Biology/ http://www.transweb.org/default.htm

And if there is more you would like to know, let us know.