[chris (OP)]

A girl out celebrating her 18th at a cocktail bar got more for her birthday than she'd bargained for - an emergency gastrectomy:

http://www.bbc.co.uk/newsbeat/19866191

But why did the nitrogen cocktail cause stomach rupture?

The BBC site above speculates that the nitrogen evolved large volumes of gas in the stomach that ruptured it. This sounds profoundly iffy to me; I cannot believe that the girl could have drunk liquid nitrogen.

I wonder, instead, whether the addition of liquid nitrogen to an alcohol-rich beverage would cause the water to free and a high-alcohol, but intensely cold, liquid ethanol residuum could then be swallowed; perhaps this very chilly liquid hit the stomach and caused snap freezing of a patch of tissue, which then ruptured...

What does everyone think?

[CliffordK]

Do they serve alcohol to 18 yr olds in Britain?
Here in the USA, a bar could get in a lot of trouble for serving drinks to people under 21..  and causing her to be hospitalized.  I can imagine the lawyers would be circling like buzzards.

One of the problem with drinks is that they are often downed in a single gulp.  So, potentially the liquid nitrogen could have reached the stomach, although I would have expected mouth and throat burns too.

I'm doubting that one could separate water from an ethanol solution in a matter of seconds with liquid nitrogen.  Saltwater brine can be separated from ice near the freezing point of water, but it is a relatively slow process.  Thus, the water/alcohol would likely remain in solution.

Alcohol does freeze, but depending on the concentration, it can be quite cold.  I'm doubting that it would be safe to drink a solution at say –50°C.

As the frozen vapour hits the stomach it rapidly warms, releasing large volumes of air which can burst the stomach.

That just sounds incorrect.  Well, partly correct.  If it is "Vapor", then the most expansion one would get would be doubling or so based on the PV=nRT.  However, if it goes down as liquid, then it could expand much much more.

When dry ice is mixed with water, it tends to get encapsulated with ice, which can slow down the melting/sublimation. 

It has been a while since I've played with liquid nitrogen, but I'm wondering if the same might be true with the liquid nitrogen, that the drops might get encapsulated.  Perhaps a strong alcohol solution would do this more than water due to the closer freezing point/boiling point temperatures.  So, perhaps the alcohol would then insulate droplets of liquid nitrogen until they arrive in the stomach.

I feel sorry for the girl.  I could imagine kids trying unique drinks at home (if they had access to liquid nitrogen).  But, it is just plain irresponsible for bars to be serving this.

[RD]

I blame Nobel laureate scientists ...

[CliffordK]

Definitely don't try that one at home.
The film states "knowledge is power".

Either there is not liquid nitrogen in the container.
Or, the person is only inhaling the gas, and not drinking the liquid.

[RD]

... Or, the person is only inhaling the gas, and not drinking the liquid.

I think the trick is to have a very small quantity of liquid nitrogen boil in the mouth : the mouth being protected by the Leidenfrost effect ...

blowing out a mouthful of liquid nitrogen ... without injury to the demonstrator.

https://en.wikipedia.org/wiki/Leidenfrost_effect

But don't swallow it ...

"Michael performed a stunt he and other students and teachers have been doing for years," says Thomas Keil, professor and head of WPI's Physics Department. "Only this time, for some reason, he swallowed the liquid nitrogen. That turned a trick into a life-threatening medical emergency...

What was really astounding about Michael's case is that the liquid nitrogen instantly expanded from a volume of about 3 or 4 cc's to about 3 or 4 liters and then dissected into five separate body compartments," says Dr. Karl D. Pilson, a trauma/critical care fellow"

http://www.wpi.edu/news/19989/nitro.html

[RD]

Re: original subject of this thread ...

   MailOnline - news, sport, celebrity, science and health stories

"‘I’d been warned by the barman the drink might make me a bit gassy, so I didn’t think too much of it, but then my stomach started to expand and I felt sick."

PUBLISHED: 22:32, 26 October 2012 | UPDATED: 00:23, 27 October 2012

http://www.dailymail.co.uk/health/article-2223745/I-killed-liquid-nitrogen-cocktail-The-novelty-drink-forced-surgeons-remove-teenagers-stomach-18th-birthday.html

[CliffordK]

Thanks for the longer description of the event and the aftermath.

Police have investigated the incident and, following Gaby’s injuries, visited every licensed premise in Lancaster to warn of what had happened. It is believed they have all voluntarily stopped using liquid nitrogen.

How prevalent is the practice in the UK?  Elsewhere?  USA?

I would think it appropriate to impose a temporary ban for the whole UK, pending review.  If a study can determine what went wrong, and come up with adequate safety guidelines, perhaps consider lifting the ban.  I don't believe there is any inherent right for licensed business establishments to serve liquid nitrogen as a drink. 

What about the use of Liquid Nitrogen in ice cream?

[evan_au]

I guess it partly comes down to expectations:-
It is possible to use liquid nitrogen to make ice-cream in 30 seconds:

You expect ice-cream to be cold, but I think it would be irresponsible to serve it at a temperature less than normal storage temperature of a freezer, about -18C, otherwise you would need safety warnings on the menu!

Ice cream would probably taste better (and have a better texture) if it were served at a temperature around -5C.

We are used to drinks with ice cubes at perhaps -18C. But temperatures near (or below) 0C must dull your sense of taste.

Perhaps dropping some "Dry ice" chips in the drink (at -78C) might give a nice show, as long as you warned people to let it stop bubbling before swallowing it (or even getting it near their lips)!
But liquid nitrogen (at -196C) is very far from normal expectations!

[yellowcat]

Do they serve alcohol to 18 yr olds in Britain?

Yes.
You can buy an alcoholic drink in the UK if you’re over the age of 18.
In a restaurant a  sixteen or seventeen-year-old  may have an alcoholic drink in conjunction with a meal  as long as the meal is not in the bar area.
Between the ages of 5 and 17, it is legally permissible for children to drink alcohol at home or at a friend's house with the permission of a parent or legal guardian.