Episode 4 Bang Goes the Theory

Hello, and welcome to Bang. We bring you the science behind the headlines

and look at the issues that have real impact on our lives.

Reports of health and safety gone mad

make the news over and over again.

But are we overreacting,

or is the world a more dangerous place?

I read statistics saying it is safer today than it was when I was a kid.

It doesn't feel like it.

When I was a kid, you didn't have to wear seat belts.

It's a bit different from when I was younger.

I think you have to be a bit more vigilant.

But also you can't bubble-wrap your kids either.

But no matter what we do, accidents will happen

at home, at work and at play.

So tonight we are looking at safety.

I'll be looking at pedestrians

and why our brains put the old and the young more at risk.

Some of the children needed a speed difference of 20mph

to notice one car's going faster than the other.

Jem plays crash-test dummy in a quest to find out

which is the safest way to face in a collision.

I'm heading for a solid steel bar.

How bad can it be?

Here we go! Three, two, one.

And I investigate a new dressing

that could drastically reduce scarring from burns.

It's so clever and so simple in one aspect of it,

it almost makes you wonder why nobody thought of it before.

That's tonight on Bang Goes The Theory.

First up tonight, we're looking at sudden cardiac arrest.

Now, a year ago, 23-year-old footballer Fabrice Muamba

collapsed out of the blue on the pitch,

and it's a story that dominated the headlines.

We tend to associate heart attacks with older people

or those with health issues,

so why on earth did this happen to a young fit sportsman?

Maggie investigates.

Since Muamba's collapse last year,

more high-profile cases have hit the news,

and, sadly, reports show that sudden cardiac death

claims the lives of around 12 young people in the UK every week.

At just 14, Isaac Fowler was one of them.

He loved sport any sport, really.

He was very laid-back and very... a very nice teenager to have around.

So just tell us, you know, exactly what happened.

It was a Saturday,

and we'd been down to Isaac's cousin's for the afternoon,

and he'd been playing basketball with him.

And we came home, I went upstairs,

and as I approached his room, he's...

I could see that he was laying on the floor.

I suddenly realised that there was something just horribly wrong,

that, you know, he wasn't conscious.

He was taken to hospital and they...

and, you know, he died at the hospital.

He'd not shown any sign of any illness, really.

He'd been perfectly fit and healthy.

So what made Isaac's heart stop?

There can be many causes,

but cardiologists first look at two things

electrical activity and structure.

At Oxford's John Radcliffe Hospital, Professor Hugh Watkins

is using ultrasound to look at the structure of my heart.

There is something extraordinary

about looking at your own heart on one of these,

cos this...isn't something I've ever done before.

So what do you look for now? What's the first thing that you would check?

Well, when we're talking about assessing

whether somebody is at risk of sudden cardiac death,

the common condition is called hypertrophic cardiomyopathy,

-and it causes thickening of the heart muscle.

-Yeah.

And the place we most typically see that is in the wall here,

the septum between the left and the right chambers of the heart.

And how thick is mine?

Our measurement comes out...8.5mm. That's very normal.

Up to 10 or 11, or even perhaps 12, would be normal.

Some patients with hypertrophic cardiomyopathy

will have 20 or 25, or even 30mm,

so their septum would be very, very thick,

very, very obvious.

But not all cases are so clear-cut.

Fabrice Muamba's heart had some thickening,

but doctors couldn't tell if it was a sign of disease,

because the hearts of elite sportsmen are often thicker than average.

And while muscle thickening is the cause

in around 50% of sudden cardiac deaths,

it's not the only one.

Next, Hugh checks my heart's electrical activity.

So, Maggie, we're going to record an ECG.

Right, so what does it look like?

-Well, you'll be pleased to know it looks completely normal.

-Good.

What we've got here is recordings of a series of heartbeats,

so this would be a single heartbeat here.

It starts with this little blip here,

which is the electricity that comes from the heart's own pacemaker,

called the sinoatrial node at the top of the heart.

That electricity then spreads through the heart,

and you get this spike there,

and that causes the heart muscle to contract, pump out the blood,

and that's the heartbeat that you feel.

And then there's a period where the electricity resets back to normal

so about a second later the whole thing can start off again.

If there were a problem, what would it look like?

I've got an example here

that illustrates one of the important ones.

The resetting period

is about double the length of time that it was in your heart.

So a cardiologist could look at this

and could make a diagnosis of a condition called long QT syndrome.

Symptoms of long QT

can include palpitations and blackouts during exercise,

but some people, like Isaac, die without warning.

A postmortem DNA test revealed he had long QT.

The disorder is caused by a faulty gene

which is passed down through the generations, it's inherited,

which then leaves a painful question for the rest of the family.

Who else is at risk?

When Hugh looked at Isaac's DNA,

he spotted a single mutation in the genetic code.

But once he'd found it,

Hugh could look for the same error in the rest of the family.

We then tested Isaac's mum,

and she has the gene.

So there may be others at risk.

So Isaac's mum has a brother, who we'll put over here.

And he's got three kids around the same age of Isaac,

so obviously, instantly there are concerns.

But it turned out that, actually, the gene change that Isaac has

and Isaac's mum has wasn't present in the uncle.

And that's a very clear result.

He's at no more risk of long QT than you or I.

We don't need to test his kids, they're all in the clear.

Isaac's mum now knows that she has long QT,

so she can control the condition with medication.

Sudden cardiac death in the young is not common,

but if your family has a history of it,

or if you're experiencing blackouts during exercise,

please contact your GP.

Heart screening isn't widely available,

but the charity Cardiac Risk In The Young

does run clinics for 14 to 35-year-olds around the country.

I brought Hani along today because Hani's extremely active,

and she had two moments of fainting.

Well, I came here today cos I was sort of

experiencing palpitations over the last few weeks.

I want to make sure that I'm fit and safe

for when I'm competing in sport in the future.

Of the young people you pick up who've got a problem,

how many of them will go on to have a sudden cardiac arrest?

Well, we expect that one in 300 people

would have an undiagnosed heart condition,

a potentially life-threatening illness.

And the vast majority of those cases

will not go on to have a sudden cardiac death,

but they need to know that they have this condition

so that they can take up various lifestyle modifications

and avoid certain high strenuous activity.

Now, how accurate are they?

Well, nothing is 100% accurate, but with these simple procedures,

we can pick up the vast majority of cases.

Thank you very much, let's have a look at your results.

Thankfully, most of the people screened here today showed no signs,

but, sadly, even screens like this are no guarantee,

and cases like Muamba will always slip through the net.

There's more information on our website, bbc.co.uk/bang.

# But you can tell by the way I cross the road

# That I've learnt all my Green Cross Code... #

While awareness of sudden cardiac arrest is relatively new,

road-safety campaigns like this one have been around for decades.

Last month, the Government announced

road-safety films would no longer be shown.

But that's not because our roads are now safe.

In fact, figures released last year

reveal that the death toll on Britain's roads

rose for the first time in a decade,

with the biggest increase amongst pedestrians.

Crossing the road is something us adults do almost without thinking

but it actually requires

quite a complex set of neurological processes,

and it can be quite risky.

I've got to find a safe place to cross,

spot if anything is coming my way, if it is, at what speed,

and then decide if I've got enough time to cross the road.

All within a handful of seconds.

I'm meeting psychologist John Wann

to find out how our brains judge the speed of an approaching car.

If you have a vehicle that's a long way away from you,

-then its optical size is quite small.

-Yeah.

As it gets closer, that optical size increases,

and that's change in size is what we call looming.

So is this what essentially we're relying on

to be able to cross the road safely?

It's one of the most important forms of information

to judge about anything coming towards you quite quickly.

It seems that judging looming

is particularly hard for two groups of people,

the over-75s and children.

WHISTLE BLOWS

To demonstrate this in kids, John has set up a test at a local school.

OK, let's go to the school hall!

But first, he's going to show me how my adult brain performs.

You're going to see one vehicle and then another,

and I just want you to tell me which one you think is going faster.

OK.

So was the first one or the second one quicker?

The first one.

The speed differences are going to get smaller and smaller

until we find out what you can just manage to judge.

What's my absolute limit in discerning the different speeds.

Your threshold at discriminating speed.

Second one...

Oh, I don't know, I don't know, I'm guessing that one.

Oh, that's tricky!

So what does that mean?

You could tell a vehicle was going faster than say 36 versus 30.

A difference of 6mph that's not too shabby, is it?

No, and on average we find adults can tell between, say, 30 and 40mph,

but not 30 and 35.

I'm above average, just say it I'm above average.

Yeah, so you're certainly above average.

So how will the children do?

-Which one was that?

-Number two.

OK, so how did they do in this test?

Well, some of the children needed a speed difference of 20mph

to notice one car's going faster than the other.

OK, and that can literally be a matter of life and death

when you're crossing the road.

Well, yes, it means if they fail to notice,

-that's going to cut down their crossing time immensely.

-Mm-hm.

Children can't differentiate between 20 and 40mph.

It is thought that this is because

sophisticated neural pathways in the brain are not fully developed yet.

It's also thought that the elderly have problems judging looming

because neural degeneration is taking place.

All this proves that crossing the road safely

is not just down to experience.

To show what this means in the real world,

John takes me out to a test track for a sobering illustration.

-OK, Liz, so we've marked out the width of a road across here.

-Yeah.

And we've got a length down there of 45 metres,

and we're going to get a car to approach us at 20mph.

And what I'd like you to do is to time it.

And it is snowing, so it couldn't be more real of a situation!

With added hazards.

-But OK, let's have a go and see what happens.

-Right.

OK, we're ready for you, Ed.

OK, so that's 5.38 seconds.

OK, well, we know that that's the sort of time

that would allow a child to cross a road of this width.

Yeah, they do have time to cross the road,

so that's pretty straightforward.

What I'd like to show you now

is what the effect is if the car's going faster,

so what we'd like you to do this time is you take the wheel,

and we're going to approach at 40mph.

To a child, this car looks like it's only travelling as fast

as the one we've just seen going at 20mph.

Right, hit 40 now.

And I'm starting the watch. One, two...

Just over two seconds.

To do the same distance, but this time at 40mph,

instead of 20, that's a huge difference,

and it means a child can't get across the road in that time.

And remember, the elderly may have the same problem.

What's become clear from John's research

is that crossing the road for children

is a very different process than it is for adults.

Now, obviously, it's still essential to teach them about road safety,

but the point here is

that children are developmentally and experientially unable

to assess looming and different car speeds efficiently.

And so it's absolutely vital that we lower our speeds

if we want to keep them safe.

Still to come tonight, Liz looks at a new way

to help recovery from one of the most common domestic accidents burns.

But first, protecting our families in car accidents.

In the UK, over 400 child passengers

are killed or seriously injured each year.

Apart from driving more carefully,

one of the few things we can practically do something about

is our children's car seats.

Buying a car seat

was probably the most important decision that we made, really,

when we were buying all our new baby equipment.

When my three children were younger,

they all romped around freely in the back of the car.

We just opened the door, shovelled them all in,

and they climbed all over the car I mean, it sounds horrendous now.

In the UK, it is mandatory for babies up to about the age of nine months

to face backwards whilst travelling.

But in Sweden, which has one of the best road safety records in Europe,

children face backwards in a car for the first four or five years.

Europe is currently reviewing

whether we should take a leaf out of the Swedes' book

and insist that children face backwards until they're older.

But how much difference does travelling backwards

actually make to our safety?

It was the Apollo moon missions of the 1960s

that gave the Swedes their inspiration.

NASA scientists knew that by placing their astronauts flat on their backs

it would lessen the effects of the significant acceleration forces

they felt as they blasted into space.

This inspired Swedish car designers

to think about seating children in a less conventional way, too.

So what kind of forces do we experience in a car crash?

And does the way we're facing make any difference,

as they seem to think in Sweden?

Well, to find out, I'm going to become a crash-test dummy.

I'm building myself a kind of go-kart to be projected by compressed air

at precise speeds along a test track.

At the end of the track...is this.

A pretty solid lamppost.

Now, the only thing that's going to make the impact here kind of bearable

is this crumple zone.

The idea of a crumple zone on this kart,

or in fact on any vehicle, is to kind of bend,

and the bending metal absorbs some of the energy of the impact.

Nonetheless, it's not going to be a wholly pleasant experience

for the fella in the hot seat.

I've kind of calculated this

so it should give a similar crash profile

to maybe hitting a lamppost in a real car in an urban environment.

I've carefully designed and built this rig

to be repeatable and predictable.

Tests make me confident I'll walk away from this.

What we don't know is exactly how my body will behave in the crash,

so I'm going to gauge the effects

using a high-speed camera and a big green pressure-sensing pad.

I wouldn't recommend this.

Erm...

I am a little nervous.

I'm forward facing, and I'm heading for a solid steel bar.

How bad can it be?

Here we go! Three, two, one.

Yeah. It was definitely an impact.

The crumple zone does its job, smoothing the intensity of the impact

as I go from 16mph to zero in a tenth of a second.

It still hurts.

The harness holds my body nicely,

but my head gets viciously thrown forwards.

But how will the reverse feel?

I don't think that a helmet would be helpful here,

so I'm relying on the padding of the headrests to cushion the blow.

I can see why kids hate being put in their car seats so much.

Let's do it!

That was like a proper shock but...

..I feel OK.

Going backwards felt better,

but what will the cameras and pressure sensor reveal?

White and blue areas correspond to little or no pressure.

Red areas are the highest pressure we're seeing.

OK, and this is then quite obviously when I was going forwards,

and you can see the straps are digging into my shoulders

-and digging in quite a lot around my waist.

-Correct.

Whereas going backwards, the whole force of the impact

is distributed quite evenly over most of my back.

Which is why there's less digging into me.

There's a little bit down at the bottom there,

but on the whole, even though quite scary,

going backwards is broadly a more comfortable way to crash.

During forward-facing collisions,

it's very common for seat belts to cause abdominal injuries.

But the more serious threat for children is to their necks,

and to see why that is, I need to look at the high-speed footage.

OK, there's the moment of impact.

Ooh!

There's an awful lot of movement in my head.

My head only comes to a stop

when eventually my neck won't stretch any further.

Right, let's see what it's like going backwards.

Ohhh!

Right, well, going backwards, the kind of overall movements

I experienced meant that my neck

never sort of went out of its comfort zone.

It was only moving within its normal range.

Whereas forward-facing, it was a different story.

And it makes me think that, overall, from the pressure results,

from the high speed and from my own experience,

that travelling backwards in a crash is probably safer.

Now, if you're a parent watching that, you might quite understandably

be feeling a bit concerned, but just some words of reassurance.

Forward-facing car seats are safe. They've been rigorously tested.

But if in the future, UK or European guidelines change

and the age limit for rear-facing seats is raised, you'll know why.

Next up, one of the biggest causes of serious burns in children

can be from a simple cup of tea.

180 kids are taken to hospital every single day with scalds from

hot drinks and they can be potentially fatal.

Some of you might find these images a little bit upsetting.

The first thing to remember is how easily heat can damage human skin.

And here's a demo to give you an idea.

OK, so the water is now at 80 degrees centigrade -

the temperature of a just-made cup of tea.

Now, obviously our skin is very different to that of a tomato's,

but just watch what happens when I place it...

into the water...for a moment.

Our skin is made up of several layers,

equating to a thickness of about 4mm.

A tomato has just one, but will react in a similar way.

Can you see that?

All the skin has been cooked

and peeled back to reveal the flesh below.

These cells are basically now dead and in humans that's called necrosis.

It just goes to show how delicate and how vulnerable our skin is.

Seven-year-old Shay was scalded two weeks ago.

So, Helen, what happened on that day?

I was cooking potatoes,

didn't realise Shay was stood next to me, so as I picked up

the pan, turned left, I splashed water on his face and chest.

Must have been quite scary for you, Shay.

-Yeah, he was screaming. It was really frightening.

-You poor thing.

'Shea here was lucky. In just a few days he's already healing well.'

You can see how it's gone from here,

where all the skin's coming off a bit, to where it is now.

And that's healed now, Mum, so that's really good.

'Even relatively low temperatures can be damaging.'

A cup of tea left for ten minutes

can still burn a child's skin in one and a half seconds.

-Oh!

-And this is our typical cup of tea scald that we see every day.

That is horrific!

Because children's skin is thinner, you get injuries like this.

Serious problems can arise during the healing process.

Bacterial infection is a major concern for young burns victims.

One of the infections we see is called toxic shock syndrome,

and that's due to the toxin released by a common bacteria -

a bacteria that's on your skin, my skin - called staphylococcus aureus.

Children below the age of four are not able to fight the toxin

and they get an overwhelming multi-organ failure if not treated.

And potentially death.

It's already really difficult to look at this,

but to think there's also the risk of actual death...that's horrific.

You may say, "Why don't we give these children antibiotics?"

That doesn't help.

It's a toxin-related disease, so giving antibiotics won't treat this.

You need to give antitoxin

and that's what these children are lacking.

They're lacking the antitoxin.

So a common scenario is the child comes back two or three days

later with a temperature.

We don't know whether that child has a cough or a cold or has

a potentially lethal infection under our dressing.

So we have this conundrum - do we leave the dressing on,

which will give the best healing for the child?

Or do we take off the dressing and risk the child scarring?

And scarring is lifelong. Although there are some treatments,

this is going to affect this child for the rest of their life.

That's just terrible to see on such a young...little being.

So we need to know when there's an infection underneath.

We want the ideal dressing of the future.

And that's just what scientists

at Bath University are trying to develop.

At a simple level it could be argued that some toxic bacteria

produce toxins which actually destroy healthy tissue.

And it's this effect we thought we could maybe

exploit in our early-warning detection system in our dressing.

Toby demonstrates how this bandage works using the closest thing

we've got to human skin - pig skin bought from the butcher's.

All right, so what happens next?

OK, we're going to infect our skin with two strains of bacteria.

One is a harmless strain of bacteria,

and here, this is a toxic strain of bacteria.

-This is an MRSA strain.

-OK, we're all familiar with that one!

-Yeah.

-That causes some serious infection.

-Yeah.

I'm going to take our prototype dressings that you see here,

and I'm going to place these onto our infected skin.

So how long do we have to wait until we see a result?

Really within minutes we should be seeing a response.

'The dressing is made from minuscule hollow nanocapsules

'filled with a fluorescent dye

'so we can see what happens under UV light.'

Oh, wow, look at that! It couldn't be clearer, could it?

There you see toxic bacteria.

It's caused our dressing to fluoresce and green that.

Yeah, and this one is absolutely fine.

So this is indicating toxic bacteria, infection present.

'And it's this signal that would alert doctors to change

'the bandage and treat the infection.'

So what exactly is happening to make your bandage fluoresce?

OK, the MRSA strain here,

in common with many other toxic staphylococcus aureus strains,

is producing toxins, and this comes along to our nanocapsules

and drills holes through the membrane.

And that allows a dye to come out.

Fantastic. It's so clever and so simple in one aspect of it.

It almost makes you wonder why nobody thought of it before.

'For now the bandage is still being trialled

but, with a system like this, unnecessary bandage changing

and potential scarring for children

and adults could become a thing of the past.'

-Thank you very much.

-Bye.

Nice to end on a positive story. That's it for tonight. Keep safe.

Visit our website at:

to watch Jem's film about air bags.

And for information about young people's safety on the internet,

follow the links to the Open University.

We'll be back after Easter.

Subtitles by Red Bee Media Ltd