Can Someone Who Is Brain Dead Open Their Eyes
A person who is brain dead is dead, with no chance of revival. Coma: A state of profound unresponsiveness as a result of severe illness or brain injury. Patients in a coma do not open their eyes or speak, and they do not exhibit purposeful behaviors. Some patients need ventilators while others do not.
They Watched Helplessly As Lemons’s Movements Gradually Stopped His Life Fading Away
Back on board the Bibby Topaz, the crew desperately tried to manually navigate back into position to save their lost colleague. As they drifted further away, they launched a remote-controlled submarine in the hope of finding him.
When it did, they watched helplessly on its cameras as Lemonss movements gradually stopped, his life fading away.
I can remember pulling the last bits of air from the tank on my back, says Lemons. It takes more effort to suck the gas down. It felt a bit like the moments before you fall asleep. It wasnt unpleasant, but I can remember feeling angry and apologising a lot to my fiancée Morag. I was angry about the damage this was going to do to other people. Then there was nothing.
The cold water and extra oxygen that had dissolved in Lemons’s blood while he was working helped him to survive for so long without air
It took around 30 minutes before the crew of the Bibby Topaz were able to regain control and restart the failed dynamic positioning system. When Youasa reached Lemons on top of the underwater structure, his body was still.
Through sheer will, Youasa dragged his fallen colleague back to the bell and passed him up to Allcock. When they removed his helmet, Lemons was blue and not breathing. Instinctively, Allcock gave him two breaths of mouth to mouth resuscitation.
Miraculously, Lemons gasped back into consciousness.
What Happens During An Ischemic Stroke
There are two main types, and each blocks blood flow in a different way.
Embolic stroke. In this case, a clot forms in some part of your body, often your heart, and starts floating through your blood vessels. Or a piece of plaque might break off and move along in your blood.
Eventually, the clot or chunk of plaque gets wedged in a small blood vessel in your brain. Once it’s stuck, blood flow to that area stops.
Thrombotic stroke. This one’s also caused by a clot in your brain. This time, a clot or blockage forms in one of the arteries that moves blood through your brain. Brain cells begin to die because blood flow is blocked.
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Agss Do Not Rely On Glycogen Or Oxidative Phosphorylation For Energy Needs During Ogd
Many organisms tolerant of low oxygen levels possess large stores of glycogen and pH buffering mechanisms that fuel and protect against pH shifts resulting from anaerobic glycolysis . Indeed, AGSs demonstrate enhanced pH buffering capacity because blood pH remains around 7.4 despite arterial PCO2 levels of 60 mmHg and arterial HCO3 concentrations tend to be higher in AGS than in rat. However, ischemia tolerance cannot be explained by enhanced peripheral stores of glycogen. Firstly, glucose derived from glycogen is not expected to reach ischemic tissue when blood flow is stopped during cardiac arrest. Secondly, addition of iodoacetate, an inhibitorof glycolysis, which would negate any benefit from glycogen, as well as the addition of NaCN, an inhibitor of cellular respiration, which would prevent use of residual oxygen in the bath, during OGD fails to increase cell death in an acute slice preparation .
How Long Can A Baby Survive Without Oxygen At Birth

In a previous blog, we detailed the long-term effects of birth asphyxia, or oxygen deprivation, that occurs during labor and delivery. The longer oxygen deprivation lasts, and the more severe it is, babies are exposed to a number of increased risks. As such, it becomes critical that the treating medical professionals adequately monitor mothers and babies to identify potential complications. From there, they must also respond appropriately and in a timely manner when these issues arise.
Some of the increased risks include:
- Serious brain damage
- Life-altering conditions such as Hypoxic-Ischemic Encephalopathy
- Death
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Common Sense Suggests He Should Have Perished After So Long At The Bottom Of The Sea
I felt very groggy and there were some flashing lights, but I dont have many lucid memories of waking up, says Lemons. I recall Dave sitting crumbled on the other side of the bell looking exhausted and not really knowing why. It was only a few days later that I realised the gravity of the situation.
Nearly seven years later, Lemons is still perplexed as to how he managed to survive for so long without oxygen. Common sense suggests he should have perished after so long at the bottom of the sea.
But it seems likely the cold water of the North Sea may have played a role around 100m down, the water was probably below 3C . Without the hot water flowing through the umbilical cord to heat his suit, his body and brain will have quickly cooled.
A sudden loss of pressure on an aircraft can leave passengers struggling to breathe in the thin air which is why oxygen masks are provided
Rapid cooling of the brain can increase survival time without oxygen, says Tipton. If you reduce the temperature by 10 degrees the metabolic rate drops by a half to a third. If you lower the brain temperature down to 30C , it can increase the survival time from 10 to 20 minutes. If you cool the brain to 20C , you can get an hour.
The pressurised gas that saturation divers usually breathe may have given Lemons an additional chance. When breathing high levels of oxygen under pressure, it can dissolve into the blood stream, giving the body additional reserves to draw on.
Going hypoxic
What Is The Prognosis For People Who Have Cerebral Hypoxia
A person with mild cerebral hypoxia may have few, if any, symptoms. They may recover without noticeable long-term effects.
The outlook for someone with cerebral hypoxia depends on:
- Length of time the brain goes without oxygen.
- Severity of brain damage.
- Age at the time of the incident .
Studies suggest that a person who comes out of a coma in less than four weeks has a better chance of recovering with little long-term damage.
Some people remain in a persistent vegetative state. This means they appear to be awake, but they cant consciously respond to commands or communicate. The odds of recovery arent good if this condition lasts for more than three months.
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Why Do Strokes Affect People In Different Ways
A stroke only affects part of your brain, and different areas of your brain control different things. So the effects of a stroke depend on how bad it is and what part of your brain it happens in. Your symptoms may help your doctor figure out where in your brain the stroke happened.
Each side of your brain controls the opposite side of your body. So a stroke on the left side of your brain affects your right side, and vice versa.
With a stroke on the right side of your brain, you might have:
- Problems judging distances and picking things up
- Trouble reading facial expressions or tone of voice
- Weakness or paralysis on your left side
With a stroke on the left side of your brain, you might have:
- Slurred speech
- Trouble getting your words out or understanding others
- Weakness or paralysis on your right side
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Ion Channels And Neurotransmitters
Recent work has shown that many of these adaptations are intertwined, especially the interactions between neurotransmitter balance and various ion channels, with multiple and apparently redundant effects. For example, gamma-aminobutyric acid induces anoxia-like decreases in excitatory post-synaptic potential activity in the normoxic turtle brain, apparently by the pre-synaptic inhibition of glutamate release. GABA also decreases ion current through glutamatergic NMDA and AMPA receptors , such that the stimulus required to generate an action potential increases more than 20-fold . However, NMDA-receptor -dependent excitotoxicity is also suppressed by -opioid receptors which exist at surprisingly high density in the turtle brain , and aid resistance to glutamate and hypoxic stress in mammals . AMPA receptor currents, meanwhile, are also reduced by activation of mitochondrial ATP-dependent K+ channels , which in turn also reduce glutamate and dopamine release in early anoxia . In longer anoxic exposures, glutamate release is suppressed by adenosine and GABA . Adenosine in turn affects channel arrest , dopamine release , NMDAR currents and cerebral blood flow .
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Why Does Oxygen Matter So Much
Your cells use oxygen to make energy. If they don’t get it, they die. It’s your blood’s job to deliver oxygen throughout your body.
Your brain is at the center of everything you do. Your ability to think, talk, feel, sing, and dance all goes back to your brain, and those brain cells need oxygen, too.
Your brain’s a real oxygen hog. It’s a small part of your body weight, but it uses 20% of your oxygen. It can’t store the oxygen, so it needs a steady flow of blood to work well. Brain cells start to die if they go without oxygen for just 3-4 minutes — and that’s exactly what happens during a stroke.
With each minute that passes, you lose about 2 million brain cells. The longer you go without oxygen, the greater your chance for brain damage that can’t be undone. After about 10 minutes, the damage can be severe.
What Are Anoxic And Hypoxic Brain Injuries
Unlike traumatic brain injuries, in which brain damage is induced by direct physical trauma, anoxic and hypoxic brain injuries are characterized by brain damage from a lack of oxygen to the brain. Anoxic and hypoxic brain injuries are commonly associated with strokes, although strokes are not the only causes of this type of brain damage.
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How Long Can The Brain Go Without Oxygen What Happens
When most people think about brain injuries, they think of some form of blunt force trauma but impact trauma is not the only potential cause of a severe brain injury. Another significant cause of brain injury is a lack of oxygen to the brain. Known as anoxic brain injuries or hypoxic brain injuries, these afflictions result from oxygen deprivation that lasts more than a few minutes.
In honor of Brain Injury Awareness Month, weve put together some information to help if someone you love has suffered an anoxic brain injury or cerebral hypoxia. Here are some things you should know about when the brain suffers from a lack of oxygen:
Tests To Confirm Brain Death

Although rare, a few things can make it appear as though someone is brain dead.
These include drug overdoses and severe hypothermia, where body temperature drops below 32C.
A number of tests are carried out to check for brain death, such as shining a torch into both eyes to see if they react to the light.
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The Cerebral Palsy Risk Factor Checklist
Any exposure to risk factors prior to conception and during pregnancy should be immediately discussed with a doctor in order to treat and minimize risk. The Cerebral Palsy Risk Factor Checklist helps parents determine if they may have been exposed to risk factors for Cerebral Palsy.
- The Cerebral Palsy Risk Factor Checklist
Symptoms Of Cerebral Hypoxia
Cerebral Hypoxia is caused by one or other underlying reasons and presents itself in varying forms, including
- Rapid breathing and heartbeat
- Stuttering
- The lips and skin get a bluish tint
- Dilated pupils
- Seizures or convulsions
- Fainting
If a person experiences Hypoxia or Anoxia due to stroke, the patient also exhibits signs of unresponsiveness.
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Why Does The Brain Need Oxygen
The brain represents just 2% of a person’s body weight, yet it uses about 20% of the body’s oxygen supply. Without it, the brain can’t perform even the most basic functions. The brain relies on glucose to power the neurons that control everything from conscious functions like planning and thought to automatic, unconscious processes like managing heart rate and digestion.
Without oxygen, the brain’s cells cannot metabolize glucose, and therefore cannot convert glucose into energy.
When your brain is deprived of oxygen, then, the ultimate cause of brain death is inadequate energy to power the brain’s cells.
How Long Can The Brain Survive Without Oxygen
Lack of oxygen in the brain will cause permanent brain damage in as little as four minutes. Another four to six minutes without the brain receiving blood will result in increased brain damage, coma and then death. In order to reduce the chances of permanent or anoxic brain damage in a person who is unconscious, CPR should be performed until their breathing and heartbeat return or until qualified medical help arrives.
The primary causes that result in an adult not breathing or having a heartbeat are accidents and injuries, excessive bleeding, infection in the bloodstream, near-drowning, drug overdose and abnormal hearth rhythms, and heart attacks that are associated with heart disease. Health issues or accidents such as choking, suffocation, drug use, carbon monoxide poisoning from malfunctioning gas appliances, electrical shock and heart arrhythmia can increase the chances of losing consciousness, which can result in anoxic brain damage.
If a person receives mild to moderate hypoxic brain damage from experiencing any of these conditions and is resuscitated, they may end up suffering from symptoms such as seizures, confusion, headaches, decreased attention span and concentration, poor coordination, occasional loss of consciousness and personality changes or mood swings.
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A Kind Of Resignation Came Over Me I Remember Being Taken Over By Grief In Some Ways Chris Lemons
It is a very strange situation, says 39-year-old Lemons. You are living on the ship surrounded by lots of people who are just a sheath of metal away, but you are completely isolated from them.
It is quicker to get back from the Moon than it is from the depths of the sea in some ways.
Divers who spend long periods in deep water need to decompress for several days in a hyperbaric chamber
The divers who do this work, however, take the risks in their stride. For Lemons, he was most concerned about spending such a long time away from his fiancée Morag Martin and the home they shared on the west coast of Scotland.
The day of 18 September 2012 had started normally enough for Lemons and the two colleagues he was diving with Dave Youasa and Duncan Allcock. The three climbed into the diving bell, which would be lowered from the ship, the Bibby Topaz, to the sea bed where they would carry out their repair work.
In many ways, it was just an ordinary day at the office, says Lemons. While not as experienced as the other two men, he had been a diver for eight years and had been saturation diving for a year and a half, taking part in nine deep-water dives. The sea was a little rough on the surface, but it was pretty clear underwater.
Chris Lemons spent 30 minutes on the sea bed after the cable that was his lifeline to the ship above him snapped in rough seas
How Long Will A Brain
A 13-year-old girl in California continues to be on a ventilator after being declared brain-dead by doctors. Although a brain-dead person is not legally alive, how much of the body will keep on working with the help of technology, and for how long?
Jahi McMath of Oakland, Calif., was declared brain-dead last month after experiencing an extremely rare complication from tonsil surgery. Jahi’s family members have fought to keep their daughter on a ventilator, but a judge has ordered that the machine be turned off next week.
A person is considered brain-dead when he or she no longer has any neurological activity in the brain or brain stem meaning no electrical impulses are being sent between brain cells. Doctors perform a number of tests to determine whether someone is brain-dead, one of which checks whether the individual can initiate his or her own breath, a very primitive reflex carried out by the brain stem, said Dr. Diana Greene-Chandos, an assistant professor of neurological surgery and neurology at Ohio State University Wexner Medical Center. “It’s the last thing to go,” Greene-Chandos said.
In the United States and many other countries, a person is legally dead if he or she permanently loses all brain activity or all breathing and circulatory functions. In Jahi’s case, three doctors have concluded that she is brain-dead.
With just a ventilator, some biological processes including kidney and gastric functions can continue for about a week, Greene-Chandos said.
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Can You Recover From Brain Damage Due To Lack Of Oxygen
A full recovery from severe anoxic or hypoxic brain injury is rare, but many patients with mild anoxic or hypoxic brain injuries are capable of making a full or partial recovery. Furthermore, symptoms and effects of the injury are dependent on the area of the brain that was affected by the lack of oxygen.
How Is Cerebral Hypoxia Diagnosed

A healthcare provider may order tests to determine a brain injurys severity. These tests include:
- Angiography to check blood flow to the brain.
- CT scan or MRI to look for signs of stroke, bleeding in the brain, brain swelling or other trauma.
- Electroencephalogram to measure electrical activity in the brain.
- Evoked potentials test to assess the brains response to sensations like touch.
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