New Scientist magazine has pondered the subject in great depth in its
latest issue, discussing the various ways of meeting one’s end, from
being burned alive to drowning and decapitation. The experts have taken
their evidence from advances in medical sciences and accounts from lucky
survivors. Whatever the mode of death, it is usually a lack of oxygen
to the brain that delivers the “coup de grace”, says the report.
Warning: Contains Graphic Images
1. Drowning
The “surface struggle” for breath
Death by drowning has a certain dark romance to it: countless
literary heroines have met their end slipping beneath the waves with
billowy layers of petticoats floating around their heads. In reality,
suffocating to death in water is neither pretty nor painless, though it
can be surprisingly swift.
Just how fast people drown depends on
several factors, including swimming ability and water temperature. In
the UK, where the water is generally cold, 55 per cent of open-water
drownings occur within 3 metres of safety. Two-thirds of victims are
good swimmers, suggesting that people can get into difficulties within
seconds, says Mike Tipton, a physiologist and expert in marine survival
at the University of Portsmouth in the UK.
Typically, when a victim realises that they cannot keep their head
above water they tend to panic, leading to the classic “surface
struggle”. They gasp for air at the surface and hold their breath as
they bob beneath, says Tipton. Struggling to breathe, they can’t call
for help. Their bodies are upright, arms weakly grasping, as if trying
to climb a non-existent ladder from the sea. Studies with New York
lifeguards in the 1950s and 1960s found that this stage lasts just 20 to
60 seconds.
When victims eventually submerge, they hold their breath for as long
as possible, typically 30 to 90 seconds. After that, they inhale some
water, splutter, cough and inhale more. Water in the lungs blocks gas
exchange in delicate tissues, while inhaling water also triggers the
airway to seal shut – a reflex called a laryngospasm. “There is a
feeling of tearing and a burning sensation in the chest as water goes
down into the airway. Then that sort of slips into a feeling of calmness
and tranquility,” says Tipton, describing reports from survivors.
That calmness represents the beginnings of the loss of consciousness
from oxygen deprivation, which eventually results in the heart stopping
and brain death.
2. Heart attack
One of the most common forms of exit
The “Hollywood Heart Attack”, featuring sudden pain, desperate
chest-clutching and immediate collapse, certainly happens in a few
cases. But a typical “myocardial infarction”, as medical-speak has it,
is a lot less dramatic and comes on slowly, beginning with mild
discomfort.
The most common symptom is, of course, chest pain: a tightness,
pressure or squeezing, often described as an “elephant on my chest”,
which may be lasting or come and go. This is the heart muscle struggling
and dying from oxygen deprivation. Pain can radiate to the jaw, throat,
back, belly and arms. Other signs and symptoms include shortness of
breath, nausea and cold sweats.
Most victims delay before seeking assistance, waiting an average of 2
to 6 hours. Women are the worst, probably because they are more likely
to experience less well-known symptoms, such as breathlessness, back or
jaw pain, or nausea, says JoAnn Manson, an epidemiologist at Harvard
Medical School. Survivors say they just didn’t want to make a fuss; that
it felt more like indigestion, tiredness or muscle cramps than a heart
attack. Then again, some victims are just in denial.
Delay costs lives. Most people who die from heart attacks do so
before reaching hospital. The actual cause of death is often heart
arrhythmia – disruption of the normal heart rhythm, in other words.
Even small heart attacks can play havoc with the electrical impulses
that control heart muscle contraction, effectively stopping it. In about
10 seconds the person loses consciousness, and minutes later they are
dead.
Patients who make it to hospital quickly fare much better; in the UK
and US more than 85 per cent of heart attack patients admitted to
hospital survive to 30 days. Hospitals can deploy defibrillators to
shock the heart back into rhythm, and clot-busting drugs and
artery-clearing surgery.
3. Bleeding to death
Several stages of haemorrhagic shock
The speed of exsanguination, as bleeding to death is known, depends
on the source of the bleed, says John Kortbeek at the University of
Calgary in Alberta, Canada, and chair of Advanced Trauma Life Support
for the American College of Surgeons. People can bleed to death in
seconds if the aorta, the major blood vessel leading from the heart, is
completely severed, for example, after a severe fall or car accident.
Death could creep up much more slowly if a smaller vein or artery is
nicked – even taking hours. Such victims would experience several stages
of haemorrhagic shock. The average adult has 5 litres of blood. Losses
of around 750 millilitres generally cause few symptoms. Anyone losing
1.5 litres – either through an external wound or internal bleeding –
feels weak, thirsty and anxious, and would be breathing fast. By 2
litres, people experience dizziness, confusion and then eventual
unconsciousness.
“Survivors of haemorrhagic shock describe many different experiences,
ranging from fear to relative calm,” Kortbeek says. “In large part this
would depend on what and how extensive the associated injuries were. A
single penetrating wound to the femoral artery in the leg might be less
painful than multiple fractures sustained in a motor vehicle crash.”
4. Fire
It’s usually the toxic gases that prove lethal
Long the fate of witches and heretics, burning to death is torture.
Hot smoke and flames singe eyebrows and hair and burn the throat and
airways, making it hard to breathe. Burns inflict immediate and intense
pain through stimulation of the nociceptors – the pain nerves in the
skin. To make matters worse, burns also trigger a rapid inflammatory
response, which boosts sensitivity to pain in the injured tissues and
surrounding areas.
As burn intensities progress, some feeling is lost but not much, says
David Herndon, a burns-care specialist at University of Texas Medical
Branch in Galveston. “Third-degree burns do not hurt as much as
second-degree wounds, as superficial nerves are destroyed. But the
difference is semantic; large burns are horrifically painful in any
instance.”
Some victims of severe burns report not feeling their injuries while
they are still in danger or intent on saving others. Once the adrenalin
and shock wear off, however, the pain quickly sets in. Pain management
remains one of the most challenging medical problems in the care of
burns victims.
Most people who die in fires do not in fact die from burns. The most
common cause of death is inhaling toxic gases – carbon monoxide, carbon
dioxide and even hydrogen cyanide – together with the suffocating lack
of oxygen. One study of fire deaths in Norway from 1996 found that
almost 75 per cent of the 286 people autopsied had died from carbon
monoxide poisoning.
Depending on the size of the fire and how close you are to it,
concentrations of carbon monoxide could start to cause headache and
drowsiness in minutes, eventually leading to unconsciousness. According
to the US National Fire Protection Association, 40 per cent of the
victims of fatal home fires are knocked out by fumes before they can
even wake up.
5. Decapitation
Nearly instantaneous
Beheading, if somewhat gruesome, can be one of the quickest and least
painful ways to die – so long as the executioner is skilled, his blade
sharp, and the condemned sits still.
The height of decapitation technology is, of course, the guillotine.
Officially adopted by the French government in 1792, it was seen as more
humane than other methods of execution. When the guillotine was first
used in public, onlookers were reportedly aghast at the speed of death.
Quick it may be, but consciousness is nevertheless believed to
continue after the spinal chord is severed. A study in rats in 1991
found that it takes 2.7 seconds for the brain to consume the oxygen from
the blood in the head; the equivalent figure for humans has been
calculated at 7 seconds. Some macabre historical reports from
post-revolutionary France cited movements of the eyes and mouth for 15
to 30 seconds after the blade struck, although these may have been
post-mortem twitches and reflexes.
If you end up losing your head, but aren’t lucky enough to fall under
the guillotine, or even a very sharp, well-wielded blade, the time of
conscious awareness of pain may be much longer. It took the axeman three
attempts to sever the head of Mary Queen of Scots in 1587. He had to
finish the job with a knife.
Decades earlier in 1541, Margaret Pole, the Countess of Salisbury,
was executed at the Tower of London. She was dragged to the block, but
refused to lay her head down. The inexperienced axe man made a gash in
her shoulder rather than her neck. According to some reports, she leapt
from the block and was chased by the executioner, who struck 11 times
before she died.
6. Electrocution
The heart and the brain are most vulnerable
In accidental electrocutions, usually involving low, household
current, the most common cause of death is arrhythmia, stopping the
heart dead. Unconsciousness ensues after the standard 10 seconds, says
Richard Trohman, a cardiologist at Rush University in Chicago. One study
of electrocution deaths in Montreal, Canada found that 92 per cent had
probably died from arrhythmia.
Higher currents can produce nearly immediate unconsciousness. The
electric chair was designed to produce instant loss of consciousness and
painless death – a step up from traditional hangings – by conducting
the current through the brain and the heart.
Whether it achieves this end is debatable. Studies on dogs in 1950
found that electrodes had to be placed on either side of the head to
ensure sufficient current passed through the brain to knock the creature
out. There have been many botched executions – those that required
several jolts to kill, or where flames leapt from the prisoner’s head,
in one case due to a damp synthetic sponge being attached to the
electrodes on the prisoner’s head, which was such a poor conductor it
was heated up by the current and caught fire.
An analysis in 2005 of post-mortem remains from 43 prisoners
sentenced to death by electrocution found the most common visible
injuries to be head and leg burns where the electrodes were attached.
The study’s senior author, William Hamilton, a medical examiner in
Florida, concluded that these burns occurred post-mortem and that death
was indeed instantaneous.
However, John Wikswo, a biophysicist at Vanderbilt University in
Nashville, Tennessee, maintains that the thick, insulating bones of the
skull would prevent sufficient current from reaching the brain, and
prisoners could instead be dying from heating of the brain, or perhaps
from suffocation due to paralysis of the breathing muscles – either way,
an unpleasant way to go.
7. Fall from a height
If possible aim to land feet first
A high fall is certainly among the speediest ways to die: terminal
velocity (no pun intended) is about 200 kilometres per hour, achieved
from a height of about 145 metres or more. A study of deadly falls in
Hamburg, Germany, found that 75 per cent of victims died in the first
few seconds or minutes after landing.
The exact cause of death varies, depending on the landing surface and
the person’s posture. People are especially unlikely to arrive at the
hospital alive if they land on their head – more common for shorter
(under 10 metres) and higher (over 25 metres) falls. A 1981 analysis of
100 suicidal jumps from the Golden Gate Bridge in San Francisco –
height: 75 metres, velocity on impact with the water: 120 kilometres per
hour – found numerous causes of instantaneous death including massive
lung bruising, collapsed lungs, exploded hearts or damage to major blood
vessels and lungs through broken ribs.
Survivors of great falls often report the sensation of time slowing
down. The natural reaction is to struggle to maintain a feet-first
landing, resulting in fractures to the leg bones, lower spinal column
and life-threatening broken pelvises. The impact travelling up through
the body can also burst the aorta and heart chambers. Yet this is
probably still the safest way to land, despite the force being
concentrated in a small area: the feet and legs form a “crumple zone”
which provides some protection to the major internal organs.
Some experienced climbers or skydivers who have survived a fall
report feeling focused, alert and driven to ensure they landed in the
best way possible: relaxed, legs bent and, where possible, ready to
roll. Certainly every little helps, but the top tip for fallers must be
to aim for a soft landing. A paper from 1942 reports a woman falling 28
metres from her apartment building into freshly tilled soil. She walked
away with just a fractured rib and broken wrist.
8. Hanging
Speed of death depends on the hangman’s skill
Suicides and old-fashioned “short drop” executions cause death by
strangulation; the rope puts pressure on the windpipe and the arteries
to the brain. This can cause unconsciousness in 10 seconds, but it takes
longer if the noose is incorrectly sited. Witnesses of public hangings
often reported victims “dancing” in pain at the end of the rope,
struggling violently as they asphyxiated. Death only ensues after many
minutes, as shown by the numerous people being resuscitated after being
cut down – even after 15 minutes.
When public executions were outlawed in Britain in 1868, hangmen
looked for a less performance-oriented approach. They eventually adopted
the “long-drop” method, using a lengthier rope so the victim reached a
speed that broke their necks. It had to be tailored to the victim’s
weight, however, as too great a force could rip the head clean off, a
professionally embarrassing outcome for the hangman.
Despite the public boasting of several prominent executioners in late
19th-century Britain, a 1992 analysis of the remains of 34 prisoners
found that in only about half of cases was the cause of death wholly or
partly due to spinal trauma. Just one-fifth showed the classic
“hangman’s fracture” between the second and third cervical vertebrae.
The others died in part from asphyxiation.
Michael Spence, an anthropologist at the University of Western
Ontario in London, Canada, has found similar results in US victims. He
concluded, however, that even if asphyxiation played a role, the trauma
of the drop would have rapidly rendered all of them unconscious. “What
the hangmen were looking for was quick cessation of activity,” he says.
“And they knew enough about their craft to ensure that happened. The
thing they feared most was decapitation.”
9. Lethal injection
US-government approved, but is it really painless?
Lethal injection was designed in Oklahoma in 1977 as a humane
alternative to the electric chair. The state medical examiner and chair
of anaesthesiology settled on a series of three drug injections. First
comes the anaesthetic thiopental to speed away any feelings of pain,
followed by a paralytic agent called pancuronium to stop breathing.
Finally potassium chloride is injected, which stops the heart almost
instantly.
Each drug is supposed to be administered in a lethal dose, a
redundancy to ensure speedy and humane death. However, eyewitnesses have
reported inmates convulsing, heaving and attempting to sit up during
the procedure, suggesting the cocktail is not always completely
effective.
The reason, say Leonidas Koniaris at the University of Miami Miller
School of Medicine, is insufficient thiopental. He and his colleagues
analysed 41 executions by lethal injection in North Carolina and
California, and compared anaesthetic doses to known effects in animal
models, such as pigs. As the same dose of thiopental is used regardless
of body weight, the anaesthesia produced in some heavier inmates might
be inadequate, they concluded.
“I think that awareness is a real possibility in a large fraction of
executions,” says Koniaris. That awareness might include feelings of
suffocation from paralysed lungs and the searing, burning pain of a
potassium chloride injection. The effect of the paralytic, however,
might mean that witnesses never see any outward signs of pain.
The Supreme Court is now going to review whether this mode of execution is legal.
10. Explosive decompression
It takes your breath away
Death due to exposure to vacuum is a staple of science fiction plots,
whether the unfortunate gets thrown from an airlock or ruptures their
spacesuit.
In real life there has been just one fatal space depressurisation
accident. This occurred on the Russian Soyuz-11 mission in 1971, when a
seal leaked upon re-entry into the Earth’s atmosphere; upon landing all
three flight crew were found dead from asphyxiation.
Most of our knowledge of depressurisation comes from animal
experiments and the experiences of pilots in accidents at very high
altitudes. When the external air pressure suddenly drops, the air in the
lungs expands, tearing the fragile gas exchange tissues. This is
especially damaging if the victim neglects to exhale prior to
decompression or tries to hold their breath. Oxygen begins to escape
from the blood and lungs.
Experiments on dogs in the 1950s showed that 30 to 40 seconds after
the pressure drops, their bodies began to swell as the water in tissues
vaporised, though the tight seal of their skin prevented them from
“bursting”. The heart rate rises initially, then plummets. Bubbles of
water vapour form in the blood and travel through the circulatory
system, obstructing blood flow. After about a minute, blood effectively
stops circulating.
Human survivors of rapid decompression accidents include pilots whose
planes lost pressure, or in one case a NASA technician who accidentally
depressurised his flight suit inside a vacuum chamber. They often
report an initial pain, like being hit in the chest, and may remember
feeling air escape from their lungs and the inability to inhale. Time to
the loss of consciousness was generally less than 15 seconds.
One mid-1960s experiment by the US Army Aeromedical Research
Laboratory in New Mexico found that a chimpanzee had a period of useful
consciousness of just 11 seconds before lack of oxygen caused them to
pass out.
Surprisingly, in view of these apparently traumatic effects, animals
that have been repressurised within 90 seconds have generally survived
with no lasting damage.
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