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Forensics: Defining Death

Picture yourself being buried alive. People living prior to the 19th century had good reason to worry about such matters, because stethoscopes hadn't been invented, and determinations of death were more a guessing game than a scientific pursuit. A weak heartbeat meant you'd probably be pronounced dead — only to wake up while your body was being prepared for burial. Fortunately, those days are gone, but plenty of trial and error took place before they could be laid to rest.

Looking for a definitive method

Determinations of death have never been straightforward. Alcohol, drugs, heart attacks, serious infections, bleeding, shock, dehydration, and other situations may render a supposed victim comatose, cold to the touch, and with weak respiration and pulse — but not dead.

Because signs of life can be difficult to accurately interpret, several methods for determining whether a person died were devised and used long ago, when science was in its infancy. Among them are

  • Tongue and nipple pulling
  • Tobacco smoke enemas
  • Insertion of hot pokers into various bodily orifices

Finally, in the 17th century, a system of waiting mortuaries — known as vitae dubiae asylums before Latin kicked the bucket — was established. In waiting mortuaries, the suspected dead were placed on cots and watched until decay set in. Although this process was unpleasant for the family of the deceased, it at least enabled a confidant proclamation of death and avoided premature burials, which weren't unheard of at the time.

The invention of the stethoscope enabled physicians to determine the presence or absence of breathing and a heartbeat, thus making death a little easier to pronounce. The development of the electrocardiogram (EKG), a device that records the electrical activity of the heart, followed, and the combination of these two devices gave physicians a much more objective measure of death. The 20th century saw the development of cardiopulmonary resuscitation (CPR) followed by the use of ventilators and pacemakers that are capable of keeping the heart and lungs working even after death. And the water suddenly became muddier. These advancements brought about the concept of brain death, which means that although the heart and lungs may be working, the brain is dead.

Currently, a death pronouncement in someone who has a heartbeat or a pacemaker and is on a ventilator requires the absence of electrical activity in the brain, which is measured on a device known as an electroencephalogram (EEG),or determination of loss of blood flow by radionuclear scanning. And even then, a pronouncement of death under those circumstances is controversial and has resulted in varying definitions for brain death

If a person on a ventilator was shot in the head, hit by a drunk driver, or otherwise ended up in that condition as a result of suspicious means, determining death becomes an issue for the coroner or medical examiner. Charges that can be filed against the shooter, driver, or other perpetrator become measurably more serious if the victim dies. Before physicians caring for the victim actually pull the plug on the ventilator, they must be absolutely sure the victim has no hope for survival. Otherwise, doctors can be implicated in the death.

Checking out causes and mechanisms of death

Simply put, the cause of death is the reason the individual died. A heart attack, a gunshot wound, and a skull fracture are causes of death. They are the diseases or injuries that alter the victim's physiology and lead to death. The mechanism of death is the actual physiological change, or variation in the body's inner workings, that causes the cessation of life.

A shot in the heart, for example, is a cause of death that can lead to one of several mechanisms of death, including exsanguination (bleeding to death) or sepsis (infection that enters the blood stream). Similarly, the victim of a skull fracture can die from direct trauma to the brain (cerebral contusion), bleeding into the brain itself (intracerebral bleed), or bleeding around the brain (subdural or epidural hematoma), all of which can lead to compression of the brain and result in a stoppage of breathing (asphyxia). Again, one cause can lead to death by several mechanisms.

Conversely, one mechanism can result from several different causes. A gunshot wound, stabbing, bleeding ulcer, or a bleeding lung tumor can cause you to bleed to death. In each case, blood loss and shock are the abnormal physiological changes.

For example, say that a man is struck by an intoxicated driver's car and severely injured. The paramedics arrive and transport him to the hospital, where he dies as a result of his injuries. The blunt trauma from the car may have caused lethal brain injuries, and the driver may be charged in the man's death. On the other hand, if the injuries weren't that severe, and the victim died from internal bleeding that paramedical and hospital personnel failed to recognize and treat appropriately, who then is responsible for the man's death? In each of these scenarios the cause of death is blunt trauma from the automobile impact, but the mechanism is either a brain contusion or exsanguination.

In cases in which the mechanism of death is unclear, the medical examiner or coroner assesses the evidence to determine what civil legal actions may follow.

Uncovering the four manners of death

The manner of death is the root cause of the sequence of events that lead to death. In other words, it answers these questions:

  • How and why did these events take place?
  • Who or what initiated the events and with what intention?
  • Was the death caused by the victim, another person, an unfortunate occurrence, or Mother Nature?

The four manners of death are

  • Natural: Natural deaths are the workings of Mother Nature in that death results from a natural disease process. Heart attacks, cancers, pneumonias, and strokes are common natural causes of death. Natural death is by far the largest category of death that the ME sees, making up about half of the cases investigated.
  • Accidental: Accidental deaths result from an unplanned and unforeseeable sequence of events. Falls, automobile accidents, and in-home electrocutions are examples of accidental deaths.
  • Suicidal: Suicides are deaths caused by the dead person's own hand. Intentional, self-inflicted gunshot wounds, drug overdoses, and self-hangings are suicidal deaths.
  • Homicidal: Homicides are deaths that occur by the hand of someone other than the dead person.

Some people, especially all you fans of The X-Files, may think of undetermined or unclassified deaths as a fifth category. These deaths are situations where the coroner can't accurately determine the appropriate category.

The manner of death of a drug abuser with a history of overdoses is likely to be either accidental or suicidal (it also could be homicidal, but it's never natural). When someone dies from a drug overdose (cause), autopsy and laboratory findings would be the same regardless of the victim's intent, but a forensic psychiatrist may be able to delve into the abuser's personal history in an attempt to find any hidden motives for suicide. Even so, the intent or lack of intent of the deceased may not be apparent, and the manner of death therefore may be listed as undetermined or unclassified. Simply put, no certain way exists for determining whether the person overdosed accidentally or purposefully.

Just as causes of deaths can lead to many different mechanisms of death, any cause of death can have several different manners of death. A gunshot wound to the head can't be a natural death, but it can be deemed homicidal, suicidal, or accidental.

Only natural deaths are caused by disease. The other categories involve trauma or drugs and may lead to civil or criminal court proceedings. Of course, even a natural cause of death may be deemed accidental, homicidal, or — in rare circumstances — suicidal. If, for example, a critically ill person is prevented from visiting a doctor or hospital, and an inheritance is at stake, the individual who prevented the victim from receiving healthcare can be charged with homicide.

Death from a heart attack because of an error during surgery is another example of a "natural" death that isn't. Although heart attack is a natural cause of death, the manner by which the heart attack occurred can be deemed accidental and lead to malpractice litigation. Likewise, this same person can have severe heart disease, be assaulted on the street, and, while struggling with an assailant, suffer a heart attack and die. The cause of death again is a heart attack, but the manner is homicide.

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