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Getting Enough Sleep? Dream on.

by William C. Dement & Christopher Vaughan

    Is eight hours' sleep enough to everyone? Have you ever heard of "sleep debt?" The following article warns us of the consequences of sleep deprivation and suggests ways to work off sleep debt.

    I once had a patient who was so sleep-deprived that she loaded her dirty dishes into the clothes dryer instead of the dishwasher. She turned on the machine, smashing china and glasses.

    Another patient went to great lengths to obtain a 50-yard-line ticket to a crucial San Francisco 49ers play-off game, but was so sleepy that he dozed off in his seat in the first quarter and stayed asleep until the game was over.

    On an everyday level, sleepy people make math errors, break things and become cross with their families, friends and co-workers. Less commonly, they make mistakes with tragic consequences. It is hard to prove how many fatal car accidents are caused by the driver's falling asleep, but my conviction is that the number is high. Laboratory experiments have confirmed that the sleep-deprived mind is prone to "microsleeps" － lapses of consciousness so brief that the subject may not even be aware of them.

    In one experiment in our laboratory at Stanford University, a volunteer who had only been allowed four hours' sleep the night before had his eyelids taped open (uncomfortable, but it doesn't hurt). He was asked to press a button every time an irregular strobe light flashed. For a few minutes he tapped the switch after each flash, on average every six seconds. Then a bright flash surged into his pupils － but he did nothing.

    "Why didn't you press the switch just now?" we asked.
    "Because there was no flash," the young man replied.

    The machines we used to monitor brain activity showed that at the very moment the light had flashed, the young man had unwittingly fallen asleep, with his eyes wide open, for two seconds. If he had been behind the wheel of a car, those two seconds could have meant disaster.

    Societal pressures to work more and at odd hours have reduced our sleep time over the past century by about 20 percent. Add to the mix our own era's drive to have and do it all － work, family, sports, hobbies － and there is very little time left for rest. I consider sleep deprivation a national emergency.

Sleep Debt and the Mortgaged Mind

    Generally, adults need to sleep one hour for every two hours awake, which means that most need about eight hours of sleep a night. Of course, some people need more and some less. Children and teenagers need an average of about ten hours.
    The brain keeps an exact accounting of how much sleep it is allowed. My colleagues and I coined the term sleep debt because accumulated lost sleep is like a monetary debt: it must be paid back. If you get an hour less than a full night's sleep, you carry an hour of sleep debt into the next day － and your tendency to fall asleep during the daytime becomes stronger.
    During a five-day workweek, if you got six hours of sleep each night instead of the eight you needed, you would build up a sleep debt of ten hours (five days times two hours). Because sleep debt accumulates in additive fashion, by day five your brain would tend toward sleep as strongly as if you'd stayed up all night. From this perspective, sleeping until noon on Saturday is not enough to pay back the ten lost hours as well as meet your nightly requirement of eight; you would have to sleep until 5 p.m. to balance the sleep ledger.
    But for most people it is difficult to sleep that long because of the alerting mechanism of our biological clock.

Wide Awake but Not Rested

    An amazingly precise biological clock within us regulates sleeping and waking, and also synchronizes a vast array of biochemical events in our bodies. It is a timepiece of such astonishing precision that people often wake up a few minutes before their alarm clocks go off.

    Most people have two peak times of alertness daily, at about 9 a.m. and 9 p.m. Alertness wanes to its lowest point at around 3 p.m.; after that it begins to build again. This explains why people who have worked hard all day will often start to feel more alert at the same time every evening despite a large accumulation of sleep debt during the day. I believe this "clock-dependent alerting" can often deceive people into thinking they are sufficiently meeting their sleep needs.

    Some years ago I had the chance to observe a striking example of clock-dependent alerting in action. It was during a visit with my daughter, Cathy, who was then a college student. At first , she was almost alarmingly apathetic and seemed to be totally uninterested in my visit. I suggested we take a walk. It was about four o'clock on a sunny late-spring afternoon. In the course of perhaps 20 to 30 minutes, Cathy changed into a talkative, informative, smiling, even vivacious person.

    The explanation for this marvelous transformation: clock-dependent alerting. Even a typically heavily sleep-deprived college student like Cathy will have a late afternoon/evening period of mental arousal. In her case it was able to abolish her fatigue. Nevertheless, my daughter was still carrying around a heavy load of sleep debt.

Sleep and Well-Being

    People sometimes ask me if the exact accounting of sleep debt could mean that they are still deprived from those all-nighters years earlier in college. We don't know what happens to sleep debt in the long term, because research has only been able to measure two-week-long periods. You may have paid off those sleep-deprived stretches when you got sick shortly afterward and slept 18 hours at a stretch. Or the brain may lose track of sleep debt accumulated months or years earlier.

    Or, accumulated sleep debt may do long-term damage to your health. In 1959 the American Cancer Society started a massive study, surveying over one million Americans about their exercise, nutrition, smoking, sleep and other habits. After tracking the group for six years, researchers found that short sleep time had a high correlation with mortality: if people had originally reported sleeping less than seven hours a night, they were far more likely to be dead within six years than those who slept an average of seven hours per night.

    After years of further research, the original results still stand: although sleep needs vary, people who sleep about eight hours, on average, tend to live longer.

    Another interesting finding from this survey was the fact that adults who said they slept ten hours or more per night also tended to have shorter lives. We speculate that these self-described long sleepers are more prone to die because they have undiagnosed sleep disorders, like sleep apnea, in which breathing stops for more than ten seconds, possibly hundreds of times a night. This causes sleep to be disrupted repeatedly by short, unremembered awakenings that may create life-threatening health problems.

    Other, more immediate effects of sleep deprivation on health and well-being have been documented by research. Studies have shown that cognitive skills and physical performance are impaired by sleep debt, but mood is affected even more. People who get less than a full night's sleep are prone to feel less happy, more stressed, more physically frail and more mentally and physically exhausted as a result. Lowering sleep debt can make us feel better, happier, more vigorous and vital.

Toward a Sleep-Smart Lifestyle

    We are generally very bad judges of our sleepiness. In 1988 my friend and colleague Tom Roth and his team at the Henry Ford Hospital's Sleep Disorders Center and Research Lab in Detroit studied a group of people who specially claimed that day-time sleepiness － a sure symptom of sleep debt － was not a problem. He first sent them to bed for eight hours － a good night's sleep, most people would agree. Upon awakening, the subjects said they felt fine.

    Yet when their daytime alertness was tested later on, more than 80 percent were not optimally alert. Of those, about 25 percent who said they felt fine were actually so in need of sleep that they posed a danger to themselves or others. Only about two in ten were optimally alert.

    You can't work off a large sleep debt by getting a good night's sleep. You have to make up as much sleep as possible and avoid amassing another large sleep debt by adopting a sleep-smart lifestyle. Here's how:

    First, establish your average personal sleep requirement in each 24-hour period to maintain a consistent level of alertness. Start with the number of hours of sleep you think you require － eight for most people. Make a point of getting that amount of sleep for several nights and pay close attention to how you feel during the day, especially during lulls on the job, after lunch or while driving.

    If you are getting drowsier on successive days, then you are getting less than your daily requirement and should add 15 to 30 minutes to your sleep time. If drowsiness continues, you can increase sleep time even more, but if you are feeling sleepy only around bedtime, you are probably close to your optimal sleep time.

    Bear in mind that you'll have to take your biological clock into account. If, like me, you are a "lark," or morning person, your strongest period of clock-dependent alerting occurs at this time. I always deal with a need for extra sleep by going to bed early rather than trying to sleep late. An "owl," or night person, however, might not be able to fall asleep early, and would be better off making up sleep debt by rising as late as possible.

    Finally, if you think you have a sleep disorder, do not hesitate to seek professional help. You can find a list of specialists on the Internet. I recommend SleepNet (www. sleepnet. com) and the American Sleep Disorders Association (www. asda. org). The National Sleep Foundation site (www. sleepfoundation. org) also contains useful information on helping you to knit up "the ravell'd sleeve of care," as Shakespeare once aptly described a good night's sleep.

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课文一

睡眠够吗？继续做梦吧。

　威廉• C•德门特 克里斯托弗•沃恩

    8小时的睡眠是不是对每个人都充裕？你听说过“睡眠债”吗？下面这篇文章提醒我们睡眠不足的后果，建议我们如何偿还睡眠债。

    我曾经有过一位病人，她由于睡眠严重不足，竟把脏碟子放进了干衣机，而不是放进洗碗机里面。她扭开干衣机的开关，哗啦啦，瓷器和玻璃器皿撞成了碎片。
    还有一位病人费了九牛二虎之力才弄到一张50码线门票，观看旧金山49淘金人协会举行的一场至为关键的加时赛，但他实在太疲倦了，头一段比赛就在座位上睡着了，一直睡到比赛结束才醒。

    几乎每天，打瞌睡的人会犯数学错误，打坏东西，或向家人、朋友和同事发火。瞌睡者因犯错而导致可悲后果的情况并不常见。很难证实，有多少起致命的车祸是由于驾驶员瞌睡引起的，但是，我相信，这个数目一定不小。实验室的试验已经证实，缺少睡眠的大脑很容易进入“短暂的昏睡”——阵发性的意识丧失，这种意识丧失的时间短得甚至连当事人都可能意识不到。

    在斯坦福大学实验室进行的一项实验中，只让一名自愿者前一天晚上睡4个小时，然后把他的眼睑固定，让他睁着眼睛，（这样做虽不舒服，但并无损害）。按照要求，每当频闪闪光灯无规律地闪光之时，他必须揿下一个按钮。最初几分钟，每闪一次他揿一下按钮，平均每6秒钟一次。而后，一道强光照入他的眼球—— 但是，他一动没动。

   “刚才你为什么不揿按钮？”我们问他。
   “没有闪光啊?”年轻人回答说。

    监控大脑活动的机器表明，就在灯光闪烁的那一刻，这位年轻人已经睁着双眼不知不觉地睡着了，睡了两秒钟。倘若他当时是在开车，这两秒钟可能就意味着灾难。

    上个世纪，迫于社会压力，我们不得不加班加点，睡眠时间减少了约20％。我们这个时代充满着各种欲望：工作，家庭，运动，业余爱好等等，使这种忙乱有增无减。因此，休息时间便所剩无几了。我认为睡眠缺失是国家的紧急情况。

睡眠债与抵押的大脑

    一般说来，成人每清醒两小时就需要一小时的睡眠，这就意味着大多数人每晚需要8个小时的睡眠。当然，有人需要的多些，有人需要的少些。儿童和青少年平均需要10个小时的睡眠时间。

    大脑对应有的睡眠量做出准确的计算。我和同事们杜撰了“睡眠债”这个词—— 睡眠缺失积累下来，就像债务一样：必须得到偿还。倘若某个晚上少睡一小时，一小时的睡眠债就被带到第二天，白天越来越想睡觉。

    在每周五天的工作日里，倘若每晚只睡6小时，而不是所需的8小时，你就欠下了10个小时的睡眠债（5天×2小时）。由于睡眠债是以累积的方式攒下的，到了第5天，你的大脑会非常想睡觉，就好像你整夜未眠似的。从这个角度说，周六睡到中午并不能满足每晚8小时的睡眠需要，也不够偿还缺失的10小时睡眠；只有睡到下午5点才能保持这本睡眠帐的平衡。

    然而，对大多数人来说，由于我们生物钟的警醒机制，我们很难睡那么长的时间。

睡意全无却没有得到休息

    我们体内的生物钟准确得简直令人叹服，我们何时睡眠，何时苏醒全由它调节，它还与我们体内的一系列生化活动保持同步。这种时钟准确得惊人，我们往往就在闹铃响前几分钟醒来。

    大多数人每天有两次警醒高峰，上午9点和晚上9点左右。警醒度在下午3点衰减至最低点，随后又开始攀高。这就是为什么那些整天努力工作，白天欠下一屁股睡眠债的人们，却常常在每晚的同一时间开始感到更加警醒。我认为，这种“依赖时钟型警醒”的情况常会使人产生错觉，以为自己的睡眠已经满足了需求。

    几年前，我曾有机会观察到一个显著的“依赖时钟型警醒”发挥效力的例子。那是我去看望女儿凯西时的事情，那时她还是个大学生。起初，她冷淡得几乎令人吃惊，似乎对我的到来一点也提不起兴致。我提议和她一起散散步。那是晚春的一个明媚的下午，4点钟左右。就在这大约20-30分钟的时间里，凯西成了一个健谈、见多识广、笑意盈盈、甚至活力四射的女孩。

    对这次奇妙转变的解释是：依赖时钟型警醒。即使像凯西这样睡眠严重不足的大学生，也会在傍晚或深夜的一段时间内精神特别兴奋。就她来说，这样可以消除疲劳。不过，我女儿依然背负着沉重的睡眠债。

睡眠与安康

    人们有时会问我，准确计算睡眠债是否意味着，数年前在大学期间常常要通宵达旦、加班加点的人至今仍被剥夺了睡眠机会呢？我们不知道，从长远的角度看，睡眠债会怎么样，因为目前的研究还只能测量为期两周的状况。或许你不久后病倒了，一睡就是18个小时。这样的话，那些因剥夺了睡眠机会而造成的种种紧张感就被一扫而光。或者，数月或数年前，你欠下了多少睡眠债，大脑也算不清了。

    或者可以说，积累的睡眠债可能会对健康造成长期损害。1959年，美国癌症协会发起了一次大规模的研究，对一百多万美国人的锻炼、营养、吸烟、睡眠以及其它方面的习惯进行调查。在对这组人进行了6年的跟踪调查后，研究者们发现，睡眠时间短缺与寿命长短有密切关系：如果人们起初称自己每晚睡眠时间不足7小时，他们就比那些睡眠时间平均每晚达7小时的人更有可能在6年内去世。
 

    经过多年的进一步研究，最初的结论依然成立：尽管睡眠需要因人而异，但一般说来，每晚睡眠达8小时的人，寿命往往会更长些。

    此次调查的另一个有趣的发现是：那些称自己每晚睡眠达10小时，甚至更多时间的成人，寿命也往往会短些。我们推测，这些自称睡眠时间较长的人更容易死亡，是因为他们患有原因不明的睡眠紊乱，如睡眠呼吸暂停，在这种情况下，呼吸会暂停10多秒钟，每晚大概会发生上百次。这使得睡眠不断受到短暂觉醒的干扰（人们醒后却不记得），可能产生一些危及生命的健康问题。

    研究也记载了睡眠被剥夺会对健康造成其他更直接的影响。研究表明，睡眠债会损害感知能力和身体的活动能力，但是，情绪更会受影响。晚上睡眠不足的人更易感到沮丧、压力、体力不支，身心疲惫。减少睡眠债可以使我们感觉更好，更加开心，更有活力和生机。

通向巧妙睡眠的生活方式

    一般说来，我们对自己的睡眠情况不能做出很好的判断。1988年，我的朋友及同事汤姆•罗斯与他在底特律的亨利•福特医院的睡眠紊乱中心与实验室小组成员们对一组人进行研究，这些人特别声明，白天想打瞌睡。这无疑是睡眠债的一种症状，并非什么大不了的问题。他首先让他们上床睡了8个小时——睡一夜好觉，大多数人都会同意。醒来时，被调查者们都说感觉良好。

    不过，在随后对他们进行的白天警醒度测试中，80%以上的人达不到最佳的警醒状态。这些人中，说自己感觉良好的人约有25%其实非常需要睡眠，以致他们对自己或他人构成了威胁。10个人中大约只有两个人处于最佳警觉状态。

    一夜好觉无法抵消大笔的睡眠债。你必须尽可能补充睡眠，采取一种巧妙睡眠的生活方式，避免积累下另一大笔睡眠债。做法如下：

    首先，确定自己每24小时期间个人平均所需睡眠量，维持一个稳定的警觉水平。按照自己认为所需的睡眠时间开始——大多数人需要8小时。连续几晚都要睡那么长时间，密切注意自己白天的感受，尤其注意上班时短暂的想睡觉，午饭后或驾驶时等不活跃期的感受。

    如果接连几天都感到瞌睡，那么，你就没有达到每天所需的睡眠量，应该再增加15到30分钟的睡眠时间。如果依然瞌睡，你甚至可以再增加睡眠时间。不过，如果只是在就寝时间感到睡意的话，你可能已经接近自己的最佳睡眠量了。
 

    记住，必须考虑到自己的生物钟。如果你也像我一样，是只“云雀”，或者说是个惯于早上活动的人，那么你很可能就会在这段时间最需要靠生物钟叫醒自己。我总是通过早睡的方式来对付额外睡眠的需要，而不会 熬夜。不过，一只“夜猫子”，或者说一个惯于晚上活动的人，可能无法很早就入眠，因此最好还是尽量晚些起床，以抵消所欠下的睡眠债。

    最后，如果你认为自己睡眠紊乱，那么在寻求专家帮助时切莫犹豫。网上可以查到专家的名单。我推荐睡眠网站( www.sleepnet.com )与美国睡眠紊乱协会网站（www. asda. org）。国家睡眠基金会网站(www. sleepfoundation. org)也有一些有用的信息，帮助你编织“那散了线的忧虑之袖”——莎士比亚在描绘美美地睡上一夜好觉时，曾有过这种贴切的比喻。

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Text 2

Three Hours to Save Your Life

by Malcolm McConnell

    On a Friday afternoon in October 1997, Earleen Cypress, a retired teacher, was in the kitchen of her Baltimore home when she heard a thud. Rushing into the family room, she found her husband sprawled on the carpet.
    "Can you hear me?" she asked. But Zanes Cypress, a former government worker, was paralyzed and unable to speak.
    Earleen immediately called 911, and an ambulance raced the couple toward the University of Maryland Medical Center in downtown Baltimore, a leading stroke-treatment facility. Less than ten minutes after the ambulance arrived, technicians slid Zanes Cypress headfirst into the opening of a CAT scanner. During the scan he was diagnosed with a major ischemic stroke.
    A blood clot blocked an artery in the left of Cypress's brain, starving nearby tissue of oxygen. Toxic chemicals from the dying tissue would soon spread to kill more brain cells, resulting in irreversible neurological damage. The entire right side of his body would likely become permanently paralyzed.

    But Dr. Marian LaMonte, co-director of the Brain Attack Team, began intravenously administering a drug called tissue plasminogen activator (t-PA). Half an hour passed, then she asked Earleen Cypress to come into her husband's room.

    Earleen was expecting the worst. But Zanes raised his right arm and leg high over the table. The next afternoon he spoke coherently, and in a few days he was discharged from the hospital in good condition.

Chain of Recovery

    Had Zanes Cypress suffered a stroke a few years earlier, the outcome would have been far grimmer, for doctors could have done little to help him. "The general standard of stroke treatment was to stabilize the patient, then let nature take its course and focus on recovery," explains Dr. Audrey Penn, deputy director of the National Institute of Neurological Disorders and Stroke.

    That has changed, and today there is an exciting group of weapons in the medical arsenal against stroke. While not all "brain attacks" can be treated, clotbusting drugs and surgical techniques can save lives or prevent loss of neurological function. Meanwhile, scientists are testing chemicals to counteract the otherwise irreversible self-destruction of brain cells following a stroke.

    The need for these therapies is critical. Some 560 000 Americans annually suffer ischemic strokes, while about 140 000 are afflicted with hemorrhagic strokes, which are caused by a ruptured vessel in the brain. Someone suffers a brain attack every 53 seconds, and every 3.3 minutes someone dies from one. The annual death toll of 160 000 makes stroke the third-leading killer, after heart disease and cancer.

    Strokes are also our leading cause of long-term adult disability. More than four million survivors struggle with problems ranging from impairment of vision or speech to major paralysis and shattered mental ability. The American Heart Association and its new division, the American Stroke Association, estimate the cost of brain attack at more than $45 billion a year.
    Unfortunately, only a fraction of stroke victims currently receive the new treatments. Fewer than five percent receive t-PA, for example.

    Why? One reason is that most people, including some members of the medical profession, are still not aware that the damage of a stroke can often be reversed, provided the victim gets immediate care. In the past, people often ignored stroke symptoms for crucial hours or even days after their onset. Many 911 dispatches did not deal with calls about possible strokes as true emergencies. And in many emergency rooms, stroke patients were given low priority.

    To fulfill their potential, the new therapies require that stroke victims reach the hospital, be evaluated, and begin treatment as quickly as possible. The clotbuster t-PA, for example, is only safe and effective if administered within three hours of the first symptoms of an ischemic stroke.

    Patients who receive t-PA during that narrow window are at least 30 percent more likely to escape disabling brain damage than those not given the clotbuster. But before doctors can safely administer t-PA, the patient must undergo a CAT scan so a radiologist can rule out hemorrhagic brain attack. (The drug cannot be used in a hemorrhagic stroke, because it could aggravate bleeding in the brain.) Researchers are now studying drugs that may offer more options for the immediate treatment of ischemic stroke. And new surgical techniques are also being developed for hemorrhagic strokes.

    Priorities for the care of stroke patients began to change in 1996, when the FDA approved t-Pa. Since then, national organizations have joined in a campaign to fight stroke, offering a model treatment concept that some experts call the Chain of Recovery.

    The Chain begins with potential victims, family members and co-workers learning to recognize the warning signs of stroke. Too many people brush off transient ischemic attacks (TIAs). The symptoms accompanying these so-called mini-strokes may last only a few minutes but often are a warning of an impending major attack.

    Unfortunately, fewer than a quarter of our hospitals today have acute stroke teams. When Dr. Mark Alberts, director of Duke University Medical Center's Stroke Acute Care Unit, urges doctors in smaller communities to take stroke treatment seriously, they often say, "I can't leave my busy practice to rush down to the hospital, read a CAT scan and decide whether a patient needs t-PA."

    Alberts counters: "Would you act differently if someone was having a cardiac arrest?" When they answer, "Of course," he points out that the ultimate reason for treating cardiac-arrest patients immediately is to prevent brain damage due to interrupted blood flow. "So why shouldn't we take action quickly when a stroke cuts the brain's blood supply?" he asks.

    Communities also need to make sure that the transportation of suspected stroke victims gets a Priority One (critical) status. Currently, only about four to ten percent of stroke victims reach hospital emergency rooms within three hours of their first symptoms. The emergency medical service (EMS) goal should be to deliver brain-attack patients to hospitals within 20 minutes of the 911 call.

    The success of Baltimore's brain-attack program, for example, reflects the advanced statewide EMS network in Maryland. Due to the diligence of 911 dispatchers, paramedics, and state-police medevac-chopper crews, stroke victims from as far away as the southern tip of the state, about 100 miles from Baltimore, can reach the medical center less than an hour after their first symptoms. "Patients, the EMS and our staff are now working as a team," notes Dr. LaMonte.

    Medical authorities also recommend that every hospital offering around-the-clock emergency care should have trained stroke-treatment specialists either on duty or on call. Ideally, a patient should be evaluated in the first 15 minutes at the hospital, while laboratory blood analysis is under way. A radiologist should read a CAT head scan within 45 minutes of the patient's arrival. This would ensure "door-to-drug" (t-PA or other treatment) time of 60 minutes following delivery to the hospital.

    Alberts recommends that doctors in private practice and HMOs create community-wide networks to provide smaller hospitals with standby stroke-treatment stall day and night.

"Drano for the Braino"

    In July 1996, just after the FDA approved the use of t-PA, Woodstock, Va., internist Dr. Greg Byrd helped colleagues at Shenandoah Memorial Hospital improve their stroke-care capabilities. That same summer they treated their first patient successfully. "Even though we're in a small, rural community," Byrd notes, "our patients are much better protected than in the past."

    In Eugene, Ore., neurologist Dr. Ray Englander led the effort to reconstruct stroke care at Sacred Heart Medical Center. "In 1996 it took us hours to evaluate and treat a stroke victim," Englander notes. "Today a patient goes from initial evaluation to CAT scan and neurological evaluation to treatment in only 45 minutes on average."

    Sacred Heart's most famous stroke survivor is Ken Kesey, the counterculture novelist. Englander successfully treated Kesey with t-PA after the writer suffered a serious stroke in October 1997. Kesey improved dramatically within days and eventually recovered fully. True to his offbeat manner, he called the clotbuster "Drano for the braino."

    Dr. Thomas Brott, chairman of the American Heart Association Stroke Council, urges all "Americans to recognize stroke as a true emergency that has to be treated quickly." Dr. John Marler, who supervised major t-PA research, agrees. "If America takes brain attack as seriously as it did heart attack in the '70s," he predicts, "we can save hundreds of thousands of people from death and disability in coming years."

    Zanes Cypress can attest to that. He has regained almost complete neurological function, including the ability to play guitar. "I feel very thankful that medical science has reached this point," he says. "If people with a stroke like mine act quickly, they, too, may recover."

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课文二

救你性命的三小时

马尔科姆•麦康纳尔

   1997年10月的一个星期五下午，家住巴尔的摩的退休教师厄尔林•塞浦瑞斯在厨房里忙着，突然她听到砰的一声。她冲进房间一看，只见丈夫手脚摊开着倒在地毯上。

  
    “你能听到我说话吗？”她问。但是，曾在政府工作过的赞恩斯•塞浦瑞斯瘫痪在地，无法应答。
    厄尔林立即拨打了911。救护车呼啸着将他们夫妇送到巴尔的摩市中心的马里兰州大学医疗中心，这家诊所在治疗中风方面处于领先地位。在救护车到达后不到十分钟的时间里，技师们径直将赞恩斯•塞浦瑞斯推入了造影扫描仪的入口。通过扫描，他被确诊为严重的局部缺血型中风。

    一团血块堵塞了塞浦瑞斯大脑左侧的一根动脉，动脉附近的组织缺氧。濒死组织产生的有毒化学物质会迅速扩散，杀死更多脑细胞，造成永久性神经损伤。他右半边身体很可能会永远瘫痪。

    但是，玛丽安•拉蒙特医生，脑疾小组的负责人之一，开始为他从静脉注入一种称为“组织血浆酶原活化剂”（t-PA）的药物。半小时后，她让厄尔林•塞浦瑞斯来到丈夫的病房。

    厄尔林做好了最坏的打算。但是，赞恩斯将右臂和右腿高高地举过了桌面。第二天下午，他说话连贯了。几天之后，他就以良好的状态出院了。

康复链
    倘若赞恩斯•塞浦瑞斯早几年中风的话，结果可能就会可怕得多。那时的医生几乎无能为力。“过去，治疗中风的通常做法是，先稳定病情，然后顺其自然，关注病人康复，”奥德丽•佩恩医生解释说。她是国家神经紊乱与中风学院的副院长。

    这种状况已经改变了，如今在医学的兵器库里对付中风有一组振奋人心的武器。尽管并非所有的脑部疾病都能够治愈，但是，粉碎血块的药物以及外科技术已经可以拯救生命或防止神经功能的丧失。科学家们正在测试某些化学药品，试图阻止中风后大脑细胞无法治愈的自毁行为。

    这些疗法是当务之急。每年大约有56万美国人患局部缺血型中风，约14万人患大出血型中风，后者由于大脑血管破裂造成。每隔53秒种就有人脑疾发作，每3.3分钟就有人死于脑疾。每年16万的死亡总数使中风成为第三大杀手，仅次于心脏病与癌症。

    中风也是慢性成人残疾的首要诱因。400多万名幸存者正在与种种疾病展开抗争，这些疾病小到视力减退或语言障碍，大到半身不遂，智力受损。美国心脏协会及其新建的分部——美国中风协会，估算每年用于治疗脑疾的费用高达450亿美金以上。

 
    遗憾的是，目前只有极少一部分中风患者接受新疗法。例如，接受t-PA治疗的患者不到5%。

    为什么呢？原因之一，大多数人，包括有些医务人员，尚未意识到，只要患者得到及时护理，是可以治愈中风损伤的。以前，人们往往忽视关键的数小时，甚至数天内的中风症状。许多911紧急寻呼并不把可能发生中风的电话作为确实需要急救的情况处理。此外，许多急诊室很少优先考虑治疗中风患者。 

    新疗法为了利用自己的潜力, 要求中风患者必须尽早送至医院，接受诊断与治疗。譬如，血块粉碎药t-PA，只有在首次出现局部出血型中风症状后3小时内使用，才能既安全又有效。

    在那个狭小的窗口接受过t-PA治疗的患者，比未接受血块粉碎药治疗的患者摆脱大脑受伤的可能性至少高出30％。但是，在医生安全使用t-PA之前，病人必须接受造影扫描，使放射学家排除大出血型脑疾的可能。（t-PA不可用于大出血型脑部中风，它会加重脑部的出血。）研究者们正在研制新药，为紧急治疗局部出血型中风提供更多的选择。用于治疗大出血型中风的外科新技术也在研制之中。

    优先治疗中风病人的问题在1996年发生变化，那一年，FDA（食品和药物部）批准使用t-PA。自此，全国性组织加入到抗击中风的运动中来，提出了某些专家们称之为“康复链”的标准治疗理念。

   该链首先从可能的患者，他们的家庭成员和学会识别中风种种先兆的同事开始。有太多人不重视短暂的局部出血（TIAs）。这些所谓“小中风”的症状只持续几分钟的光景，但它们常常是重症临近的警报。

    不幸的是，目前，仅有不到1/4的医院备有急性中风治疗小组。杜克大学医学中心的中风紧急治疗组的负责人马克•艾伯茨医生督促小型社区的医生们认真对待中风治疗时，他们常常会说：“我不能放下手中正忙着的事情匆忙跑到医院，学习造影扫描，决定病人是否需要t-PA治疗。”

    艾伯茨反驳说：“如果患者心搏停止，你的做法是不是就不同了？”当他们回答“当然”时，他就指出,紧急治疗心博停止病人的最终目的正是防止因血流中断造成脑部损伤。“所以，我们怎能不在中风切断大脑供血之时迅速采取行动？”他问道。

    同样，社区也要确保第一时间优先运送有中风危险的患者去医院。目前，仅有4%到10%的中风患者在病症首次发作的三小时内抵达医院急救室。紧急治疗服务（EMS）的目标应该是，接到911急救电话20分钟内将脑疾病人送至医院。

    以巴尔的摩脑疾研究项目为例，它的成功反映出了马里兰州先进的的州际EMS网络。由于911调度员、护理人员，以及州警局医用直升机机组成员的共同努力，远离巴尔的摩100英里、远在马里兰州最南端的中风患者，也能够在病情发作一小时内抵达医疗中心。“病人，EMS以及我们的职员就像在一个工作组里工作，”拉蒙特医生强调说。

    医疗权威也建议，每家提供全天候紧急护理的医院应该让训练有素的中风专家当班或日夜候诊。理想的状况是，任何一名病人在入院15分钟内就接受诊断，实验室同时进行血样分析。放射学家应在病人抵达45分钟内对其进行头部造影扫描。这样就可以保证“出门至用药”（t-PA或其它疗法）在病人抵达医院一小时之内完成。

    艾伯茨提议，私立医疗机构与心脏维护组织的医生应当在社区范围内建立网络，为小医院提供全天候备用治疗中风的场所。

“大脑炸药”
    1996年7月，就在食品与药物管理局刚刚批准弗吉尼亚州的伍德斯托克市使用t-PA之后，内科医生格雷格•伯德在谢南多厄纪念医院帮助同事们提高治疗中风的能力。同年夏天，他们成功治愈了首位病人。“尽管我们是在一个乡下的小社区，”伯德强调说，“我们的病人得到比以前更好的护理。”

    在俄勒冈州的欧仁，神经病学家雷•英格兰德在圣心医疗中心领导重建中风救治所。“1996年，诊治一名中风病人得花数小时，”英格兰德指出。“如今，从初诊到造影扫描，从神经病学家的诊断到治疗，平均只需45分钟。”

    圣心医疗中心治愈的最著名的中风患者是金•凯西，一名反正统文化的小说家。1997年10月，凯西患了严重的中风，英格兰德用t-PA成功地把他治愈。几天里凯西就迅速好转，最终完全康复。他把这种粉碎血块的药称为“大脑炸药”-- 这倒非常符合他离经叛道的风格。

    托马斯•布洛特医生，美国心脏协会中风委员会的主席，督促所有的“美国人要认识到，中风是一种真正需要得到迅速治疗的急症。”监管t-PA重大研究的约翰•马勒医生对此表示赞同。“如果美国对待脑疾像在70年代对待心脏病那样认真的话，”他预测说，“我们以后就可以将成千上万的人从死亡和残疾中拯救出来。”

    赞恩斯•塞浦瑞斯能够证明这一点。他的神经功能，包括弹奏吉他的能力，已几乎完全恢复了。他说，“感谢医学发展到了这种程度，如果象我这种中风的人赶紧采取行动，也会康复的。”

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