Inhaling xenon could prevent life-threatening brain damage in patients who suffer severe head injuries, a study suggests.
Giving mice the gas after they suffered blows to the head improved their survival rates, cognitive function and memories.
Xenon, which is already used as an anaesthetic, is thought to reduce the stimulation of neurotransmitters which peaks after a traumatic brain injury (TBI).
This can then damage nerve cells, which is known as a secondary injury and often occurs within minutes of the initial blow to the head.
An atmospheric gas could prevent brain damage in those who suffer head injuries (stock)
The research was carried out by Imperial College London and led by Dr Rita Campos-Pires, from the department of surgery and cancer.
Dr Campos-Pires said the findings add to evidence that suggests xenon could be used after head injuries to prevent secondary injuries developing.
She said: 'Xenon appears to act in a variety of ways.
'But one of the most likely mechanisms to explain its protective effects on brain tissue is by inhibiting receptors in the brain known as NMDA receptors, that become over-activated following a brain injury.'
TBI can occur from incidents such as falls or car accidents, and affect around 326 people in every 100,000 in Europe.
Those who survive often suffer from debilitating conditions that affect their ability to work or socialise.
The injuries also raise their risk of cognitive decline, Alzheimer's and even an early death, studies have shown.
No drugs are proven to protect against brain damage following a TBI, with care currently focusing on rehabilitation.
Xenon is proven to be safe, and can be inhaled or administered via mechanical ventilation to numb patients in intensive care.
It has also been shown to prevent brain injury when blood supply is cut off to the vital organ. However, little is know about its effectiveness outside of the laboratory.
To put this to the test, the researchers analysed 72 adult mice, aged two-and-a-half months.
Some were inflicted with a TBI before receiving xenon or no treatment, while others were given the gas but no injury.
A day later, all the animals' cognitive functions were assessed via a 15-point score that looked at their movement, balance and general behaviour.
A traumatic brain injury (TBI) typically occurs following a violent jolt to the head, such as during a car accident.
Objects penetrating the brain tissue, such as a bullet, can have the same effect.
TBI is the most common cause of death and disability in people aged one-to-40 in the UK.
Some 1.4million people attend A&E every year in England and Wales after suffering a blow to the head.
And in the US, an average of 155 people died every day of 2014 from injuries that included TBI.
In mild cases, brain cells may just be temporarily affected.
But in more serious incidents, the
