This is the moment a father-of-three suffers from a sudden brain bleed that kills up to 50 percent of patients.

Thomas Gallagher, from Michigan, was drinking water in the kitchen after a day out when he suddenly felt a ‘barbaric’ pain shooting through his head and the back of his neck.

After collapsing on his child’s bed and crying out in pain, he was rushed to hospital and then airlifted to a nearby unit — where he was diagnosed with a subarachnoid hemorrhage, or a bleed between the brain and brain lining.

His wife Grace said she feared that when her husband was airlifted to hospital she would never see him again. 

Terrifying moment father-of-three experiences sudden brain bleed

Thomas Gallagher, from Michigan, had been on a family day out with four-year-old son Auggie hours before the sudden brain bleed

She wrote on Instagram: ‘When they closed the helicopter doors, I thought it might be the last time I would see him.

‘Basically, all I was reading was that Tom was about to die.’

Subarachnoid hemorrhages are so deadly because they can cause other blood vessels to tighten — reducing blood flow to the organ and leading to a stroke. 

They can also put pressure on the brain, raising the risk of blood vessels inside the organ bursting.

The bleeding is often caused by a weakened blood vessel bursting and bleeding into the space between the brain and its protective membrane.

The main symptom this causes is a sudden and severe headache, which can be mistaken for other conditions and take hours to diagnose.

Treatment normally involves surgery, with a neurosurgeon clipping the ruptured blood vessel closed to halt the bleeding. 

Thomas Gallagher is pictured above after suffering from the brain bleed, experiencing the symptom of a sudden and severe headache

Mr Gallagher is pictured above in hospital with his wife Grace as he recovers from his medical episode

Interview: Emilia Clarke, 33, has revealed she now considered the life-threatening brain haemorrhage she had at 24 to be ‘a good thing’

The American Heart Association’s journal has published a study warning the fatality rate for the condition is between 22 and 50 percent.

In many cases, survivors suffer from long-term complications including paralysis and troubles with their memory and concentration. 

About 28,000 people suffer from the strokes every year, typically aged 40 to 60 years old — with a quarter of patients are under the age of 45 years.

The most common cause of the condition in younger age groups is motor vehicle crashes, according to the Cleveland Clinic. High blood pressure, smoking and a family history of the condition may also raise someone’s risk of suffering from it.

Previously, Game of Thrones star Emilia Clarke — who plays Daenerys Targaryen — has also suffered from this brain bleed, which started just after she had finished filming for the first series. 

She had an emergency three-hour surgery and afterward experienced excruciating pain, vision problems and aphasia — where damage to the brain affects a person’s ability to speak and write. At one point, she couldn’t remember her own name.

Mrs Gallagher revealed that the family had been on a fishing trip with their eldest Auggie, four, in the hours before the sudden stroke.

Security cameras at home caught the moment the stroke began and the family’s prompt reaction.

Mr Gallagher spent ten days in ICU receiving treatment but has now been discharged and sent home for recovery.

His wife says he has ‘a lot of limitations’ now, including to his strength, stamina and coordination.

The children — including Murphy, two, and Lottie, one — are said to be being very patient with their father and helping with his recovery.

He is not expected to be able to return to running the family’s small business, which they say they will now close permanently.

Revealing their battle online, the family is now appealing for donations to help cover medical costs via GoFundMe.

They have so far raised $4,200 out of the $5,500 target.

Mr Gallagher had previously suffered from regular migraines but had never suffered from a severe brain bleed.