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http://dotsub.com/view/97e72d9c-4b84-4675-a0bc-b1e0caf3c439
Elliot Krane: 慢性疼痛之谜
我是一名儿科医生和麻醉师， 我以帮孩子们入睡为生。 （笑声） 我也是一名大学教师，所以我免费让听我讲课的人打瞌睡。 （笑声） 但我主要从事的 还是提供管理疼痛的服务 在帕罗奥多市 斯坦福大学的 帕卡德儿童医院。 从经验上来讲， 根据我20或25年的执业经验 今早，我想告诉你的是， 疼痛是一种病。
大多数时候， 你会认为疼痛是一种症状。 大多数情况下，这种想法是正确的。 它的确是肿瘤和感染的症状 或者是发炎、手术中的症状。 但有约10％的情况下， 病人虽然已经从上述情况下康复， 但疼痛依然继续。 有时候持续几个月 甚至持续几年。 当这种情况发生时， 疼痛本身就是一种疾病。 在我向你讲解它是如何发生 我们可以采取何种措施之前， 我想向你展示一下，病人对此的感受。 如果可以，请你想象一下， 我用这根羽毛挠你， 就像现在我挠自己的手臂一样。 现在，我要你想象 如果我是用这个（喷火枪）“挠”你呢？ 请大家只管坐好！ （笑声） 非常迥异的感觉。 这跟慢性疼痛有什么关联呢？ 如果这两个感觉被混淆了 想象一下你的生活将会怎样 如果我是用这根羽毛去挠你， 结果你的大脑却告诉你 你现在的感觉是灼伤-- 这就是我的患者对慢性疼痛的感受。 事实上，想象下更糟糕的情况。 想象下我用这根羽毛去挠你孩子的胳膊， 结果他们的大脑却告诉他们 他们感受到的是这个灼热的喷火枪。
这就是我的患者，钱德勒的遭遇， 就是照片中的女孩。 正如你看到的，她是个漂亮的年轻姑娘。 去年当我遇到她时，她16岁， 她渴望成为一名专业的舞者。 在她的一次舞蹈排练中， 她摔倒压在了自己向外伸展的手臂上，并且扭伤了手腕。 就像当时钱德勒的想法， 你可能也认为这就是人生当中 一次普通的受伤。 用绷带缠起来 吃点布洛芬，一周或两周 事情就会结束。 但是在钱德勒这次的遭遇中，这只是故事的开始。 图中是当时她手臂的情况 当她来到我的诊所时，已经是扭伤发生约三个月后 你可以看到手臂已经变色 有点青紫 摸上去像尸体一样冷 肌肉僵硬-- 我们通常所说的瘫痪性肌张力异常。 疼痛从她的手腕蔓延到手掌， 到手指，又从手腕蔓延到手肘， 一直到她的肩膀。
但最糟糕的 不是每天24小时的自发性疼痛。 最糟糕的是她患上痛觉超敏症 这是一个医学术语 说的就是我刚才用羽毛和喷火枪所演示的那种情况 轻微的触碰她的手臂 触碰手掌， 即使是她自己穿衣服时触碰到手袖、衣物 也会造成难以忍受的烧灼痛
神经系统怎么会犯这样的错呢？ 神经系统 怎么会误解一个本来无害的触觉呢？ 就像是把手的触摸 误解成 触摸火焰的恶意感觉。 把身体里的神经系统 想象成你家里的电线电路。 在你家里，电线布满在墙壁里， 从灯的开关到天花板上的接线盒 从接线盒又到灯泡。 当你打开开关的时候，灯泡亮了 等你关闭开关的时候，灯泡熄灭。 假设神经系统就是这样。 如果你用锤子敲大拇指， 你手臂里的电线——当然，我们称为神经—— 在脊髓里传递信息到接线盒 新电线，新的神经 把信息运送到大脑 因此你能自觉意识到你的大拇指受伤了。
这个情况，当然，是发生在身体里的 实际上更复杂一些。 相反 脊髓里的接线盒 仅仅是一段神经联系另一段神经的地方 通过释放这些小棕色块 也就是被称为神经递质的化学信息 以一对一的线性方式 事实上 是神经递质发散出三维空间-- 在脊髓里横向、纵向、以及上下地-- 它们和其他邻近的细胞之间 开始发生反应。 这些细胞，称为神经胶质细胞， 它们曾经被认为 是脊髓里不重要的结构构件 仅仅是把其他重要的东西连接在一起， 比如说神经。 结果却发现 在疼痛的案例中，神经胶质细胞 在调节，扩大 和歪曲 感觉体验的作用中起着非常重要的作用。 这些胶质细胞活跃起来。 它们的脱氧核糖核酸开始合成新的蛋白质 同时发散出来 与邻近的神经发生反应。 释放出神经递质。 神经递质又被发散出来 激活了邻近的胶质细胞，然后如此循环往复， 直到 神经反射。
几乎就像是有人到你家 重新在你墙壁里布线， 结果你下次打开灯的开关， 却意外的冲了三次马桶， 或者是启动了洗碗机， 或者是电脑显示器被关闭。 乱套了！ 但事实上， 这就是患上慢性疼痛后，会发生的事情。 也是为什么疼痛本身会变成一种疾病。 神经系统有可塑性。 对刺激做出反应 它会改变，也会变异。
那我们该怎么办呢？ 针对钱德勒这样的情况我们该怎么做呢？ 我们用相对粗糙的一种方式来治疗这些患者 目前是这样的。 我们用控制症状的药物来治疗 也就是止疼药 坦白说，对于这种病 不是很有效。 我们只是让那些吵闹的神经 消停下来， 用局部麻醉来使它们进入睡眠。 最重要的是，我们所做的 只是用枯燥且常不舒服的 物理治疗和职业治疗法 来在神经系统里维持神经 使它们在日常生活的 感官活动中 做出正常的反应。 对此，我们用密集的心理治疗方案 进行全力的配合 解决那些 伴随严重慢性疼痛而来的 沮丧、绝望和抑郁。
我们很成功！ 正如你从这个视频短片中看到的钱德勒， 在我们遇见她两个月之后， 她正做着后空翻。 昨天我刚和她一起吃了午饭， 因为现在，她是在长滩学习舞蹈的一名大学生。 她现在简直是棒极了！
未来更加美好！ 未来有希望 开发新的药物 不是那些只会控制症状的药物 它们仅仅是粉饰问题。 而是，正如我们现在看到的， 去开发那种治病的药物 能真正从根本上解决问题 对付神经胶质细胞 或对付那些由神经胶质细胞产生的 有害的蛋白质 它们溢出后使中枢神经系统产生发条拧紧现象， 产生神经的可塑性， 因此就有可能 歪曲和扩大了 我们称为疼痛的感觉体验。 所以，我有一个愿望
在将来 乔治·卡林的预言会实现， 他说，“我的哲学是： 没痛就不痛。”
非常感谢
（鼓掌声）



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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 a 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 -- pain-killers -- 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)