Elliot Krane: The mystery of chronic pain

I'm a pediatrician and an anesthesiologist,

so I put children to sleep for a living.

(Laughter)

And I'm an academic, so I put audiences to sleep for free.

(Laughter)

But what I actually mostly do

is I manage the pain management service

at the Packard Children's Hospital up at Stanford in Palo Alto.

And it's from the experience

from about 20 or 25 years of doing that

that I want to bring to you the message this morning,

that pain is a disease.

Now most of the time,

you think of pain as a symptom of a disease,

and that's true most of the time.

It's the symptom of a tumor or an infection

or an inflammation or an operation.

But about 10 percent of the time,

after the patient has recovered from one of those events,

pain persists.

It persists for months

and oftentimes for years,

and when that happens,

it is its own disease.

And before I tell you about how it is that we think that happens

and what we can do about it,

I want to show you how it feels for my patients.

So imagine, if you will,

that I'm stroking your arm with this feather,

as I'm stroking my arm right now.

Now, I want you to imagine

that I'm stroking it with this.

Please keep your seat.

(Laughter)

A very different feeling.

Now what does it have to do with chronic pain?

Imagine, if you will, these two ideas together.

Imagine what your life would be like

if I were to stroke it with this feather,

but your brain was telling you

that this is what you are feeling --

and that is the experience of my patients with chronic pain.

In fact, imagine something even worse.

Imagine I were to stroke your child's arm with this feather,

and their brain [was] telling them

that they were feeling this hot torch.

That was the experience of my patient, Chandler,

whom you see in the photograph.

As you can see, she's a beautiful, young woman.

She was 16 years old last year when I met her,

and she aspired to be a professional dancer.

And during the course of one of her dance rehearsals,

she fell on her outstretched arm and sprained her wrist.

Now you would probably imagine, as she did,

that a wrist sprain is a trivial event

in a person's life.

Wrap it in an ACE bandage,

take some ibuprofen for a week or two,

and that's the end of the story.

But in Chandler's case, that was the beginning of the story.

This is what her arm looked like

when she came to my clinic about three months after her sprain.

You can see that the arm is discolored,

purplish in color.

It was cadaverically cold to the touch.

The muscles were frozen, paralyzed --

dystonic is how we refer to that.

The pain had spread from her wrist to her hands,

to her fingertips, from her wrist up to her elbow,

almost all the way to her shoulder.

But the worst part was,

not the spontaneous pain that was there 24 hours a day.

The worst part was that she had allodynia,

the medical term for the phenomenon that I just illustrated

with the feather and with the torch.

The lightest touch of her arm --

the touch of a hand,

the touch even of a sleeve, of a garment, as she put it on --

caused excruciating, burning pain.

How can the nervous system get this so wrong?

How can the nervous system

misinterpret an innocent sensation

like the touch of a hand

and turn it into the malevolent sensation

of the touch of the flame?

Well you probably imagine that the nervous system in the body

is hardwired like your house.

In your house, wires run in the wall,

from the light switch to a junction box in the ceiling

and from the junction box to the light bulb.

And when you turn the switch on, the light goes on.

And when you turn the switch off, the light goes off.

So people imagine the nervous system is just like that.

If you hit your thumb with a hammer,

these wires in your arm -- that, of course, we call nerves --

transmit the information into the junction box in the spinal cord

where new wires, new nerves,

take the information up to the brain

where you become consciously aware that your thumb is now hurt.

But the situation, of course, in the human body

is far more complicated than that.

Instead of it being the case

that that junction box in the spinal cord

is just simple where one nerve connects with the next nerve

by releasing these little brown packets

of chemical information called neurotransmitters

in a linear one-on-one fashion,

in fact, what happens

is the neurotransmitters spill out in three dimensions --

laterally, vertically, up and down in the spinal cord --

and they start interacting

with other adjacent cells.

These cells, called glial cells,

were once thought to be

unimportant structural elements of the spinal cord

that did nothing more than hold all the important things together,

like the nerves.

But it turns out

the glial cells have a vital role

in the modulation, amplification

and, in the case of pain, the distortion

of sensory experiences.

These glial cells become activated.

Their DNA starts to synthesize new proteins,

which spill out

and interact with adjacent nerves,

and they start releasing their neurotransmitters,

and those neurotransmitters spill out

and activate adjacent glial cells, and so on and so forth,

until what we have

is a positive feedback loop.

It's almost as if somebody came into your home

and rewired your walls

so that the next time you turned on the light switch,

the toilet flushed three doors down,

or your dishwasher went on,

or your computer monitor turned off.

That's crazy,

but that's, in fact, what happens

with chronic pain.

And that's why pain becomes its own disease.

The nervous system has plasticity.

It changes, and it morphs

in response to stimuli.

Well, what do we do about that?

What can we do in a case like Chandler's?

We treat these patients in a rather crude fashion

at this point in time.

We treat them with symptom-modifying drugs --

painkillers --

which are, frankly, not very effective

for this kind of pain.

We take nerves that are noisy and active

that should be quiet,

and we put them to sleep with local anesthetics.

And most importantly, what we do

is we use a rigorous, and often uncomfortable, process

of physical therapy and occupational therapy

to retrain the nerves in the nervous system

to respond normally

to the activities and sensory experiences

that are part of everyday life.

And we support all of that

with an intensive psychotherapy program

to address the despondency, despair and depression

that always accompanies

severe, chronic pain.

It's successful,

as you can see from this video of Chandler,

who, two months after we first met her,

is now doings a back flip.

And I had lunch with her yesterday

because she's a college student studying dance at Long Beach here,

and she's doing absolutely fantastic.

But the future is actually even brighter.

The future holds the promise

that new drugs will be developed

that are not symptom-modifying drugs

that simply mask the problem,

as we have now,

but that will be disease-modifying drugs

that will actually go right to the root of the problem

and attack those glial cells,

or those pernicious proteins

that the glial cells elaborate,

that spill over and cause this central nervous system wind-up,

or plasticity,

that so is capable

of distorting and amplifying

the sensory experience that we call pain.

So I have hope

that in the future,

the prophetic words of George Carlin will be realized,

who said, "My philosophy:

No pain, no pain."

Thank you very much.

(Applause)