|
Lung Disease Treatment Without Major Surgery Hospitals are testing new procedures to help patients with a devastating lung disease breathe easier without major surgery. More than 15 million people have been diagnosed with chronic obstructive pulmonary disease, or COPD, according to the Centers for Disease Control and Prevention. Millions more may be unaware they have it. The disease is the third leading cause of death in the U.S., after heart disease and cancer. COPD costs nearly $30 billion in direct health care expenditures. COPD is mainly caused by smoking, but the condition also has been linked with secondhand smoke, air pollution and workplace dust and chemicals. Genes may play a role in why some smokers develop it and some don't. Some patients with severe cases of COPD may be referred for surgery, during which the diseased part of the lung is removed. But the risky and costly procedure isn't often used, partly because recovery is long and many patients experience complications after surgery. More than two dozen U.S. medical centers are currently testing a technique that places metal coils into the lung using special scopes inserted through the mouth or nose. Once in place, the coils compress the diseased tissue and allow the healthier parts of the lung to breathe more freely. Other hospitals are investigating a small-umbrella shaped valve that redirects air from less healthy to more healthy parts of the lung. 'If successful, we will be able to help a significant number of patients have an improved quality of life, and potentially improve survival in a noninvasive manner,' says Atul C. Mehta, an interventional pulmonologist at Cleveland Clinic, one the centers participating in the coils trial. In Europe, where the coils have been approved for use since 2008, studies have shown the treatment is safe for patients and results in significant improvements in pulmonary function, exercise capacity and quality of life. Current U.S. research is being funded by PneumRx Inc., the Mountainview, Calif., maker of the coils. While smokers can prevent COPD by quitting before it develops, once the lungs are damaged it isn't reversible. Most patients are managed with the use of inhaled medications called bronchodilators, oxygen and pulmonary rehabilitation. Mary Morgan, a nurse who lives in Parma, Ohio, was diagnosed seven years ago with emphysema, a form of COPD. Still, she continued to smoke for a few more years because the disease 'wasn't bothering me,' she says. Two years ago, the 55-year-old came down with pneumonia and had to call 911 because she couldn't breathe. She quit smoking but needed to be on oxygen all the time. She gasped for breath often and wasn't able to speak more than a few words at a time. 'It gets to the point where you are living in such misery that you just don't want to go on,' Ms. Morgan says. After completing a pulmonary rehabilitation program, Ms. Morgan was accepted into the coils trial at the Cleveland Clinic last December. Dr. Mehta and another pulmonologist placed 12 of the small devices in her right lower lung. She was discharged from the hospital after just one night and says she felt improvements almost immediately. Tests a month later showed her breathing had improved by 30%. She is still on supplementary oxygen and is scheduled to have additional coils inserted in her left lung later this month. COPD includes two main conditions, emphysema and chronic bronchitis, and most patients have elements of both. Emphysema, as it advances, destroys the air sacs, or alveoli, that exchange air between the lungs and surrounding tissue and bloodstream. Diseased portions of the lung overinflate, become inelastic and trap air. Meanwhile, the expanded sacs push against the lung's healthier areas. Patients may feel as if they are suffocating. Medications may cease to work. More severe cases of COPD affect an estimated three to four million people in the U.S. Dr. Mehta estimates as many as one million may be candidates for some form of lung volume reduction through surgery or the new less-invasive coil procedure. The surgery requires a large incision, or several small ones, in the chest to excise diseased tissue. The aim is to allow the patient to breathe easier with the remaining healthier portion of the lungs. In a large study a decade ago, called the National Emphysema Treatment Trial, the surgery didn't show an overall survival advantage over medical management. It did show an advantage in patients whose disease was worse in upper lobes of the lungs and whose exercise capacity was low. Still, the procedure is little used. Complication rates are high. Relatively few centers in the country offer the procedure. 'In the right patients, we've proven that lung reduction surgery works, but doctors aren't referring patients for the procedure and patients aren't interested in doing major surgery,' says Frank Sciurba, director of the Pulmonary Function and Exercise Physiology Lab at the University of Pittsburgh Medical Center and principal investigator for its part of the coils-implant trial. One aim of the trial, he says, is to determine which patients have the right lung structure and physiology to benefit from the coils procedure. The coils trial isn't studying costs. 'In the long run the hope is this could be more cost-effective,' says Dr. Sciurba, by reducing hospitalization costs, complications and readmissions. A PneumRx spokeswoman says the coils procedure in Europe costs $15,000. 'We aren't yet far enough along in the U.S. market to have a valid comparison,' she says. Experts have had mixed results with other nonsurgical techniques, such as chemical sealants and steam to destroy the diseased part of the lung. In another current clinical trial, researchers are guiding a small, umbrella-shaped valve into the airways that redirects air from less healthy to more healthy parts of the lung while letting trapped air escape. An earlier trial of the valves ended without meeting the requirements for Food & Drug Administration approval, but Redmond, Wash., device maker Spiration Inc., is funding a new trial to determine if the procedure can help reduce over-inflation of the lung and improve overall lung function and quality of life. D. Kyle Hogarth, director of bronchoscopy and assistant professor of medicine at the University of Chicago who is leading an arm of the valve study there, says a possible risk to the use of any device is infection from foreign bodies inserted into the lung. While coils aren't designed to be removed, valves could be removed if necessary, he says. Because emphysema can affect individual patients' lungs differently, in the future, patients may end up qualifying for both coils and valves, 'to treat different types of abnormalities and breathing problems,' Dr. Hogarth says. 为了帮助身患致命肺病的病患在不动大手术的情况下也能更轻松地呼吸，各家医院正在测试新的治疗手段。 据美国疾病控制和预防中心(Centers for Diesease Control and Prevention)称，超过1,500万人已确诊患有慢性阻塞性肺疾病（或简称为COPD）。另外还有数百万人可能不知道自己身患此病。在美国，该疾病是排在心脏病和癌症之后的第三大死因。在直接医保支出中，治疗慢性阻塞性肺疾病的相关费用将近300亿美元。 吸烟是引发慢性阻塞性肺疾病的主要原因，但它也与二手烟、空气污染以及工作场所的粉尘和化学物质有关。基因可能也会起到一些作用，这也就是为什么有些烟民会发展成COPD患者、而有些却并未患病的原因。 一些病情严重的COPD患者可能得送去做手术，通过手术摘除肺部的病变部位。但这种有风险、耗财力的治疗手段并不常用，一部分原因是因为手术后的恢复期较长，而且很多病人还会患上术后并发症。 目前，美国有20多个医疗中心都在测试一种新技术：将特殊的内窥镜通过口腔或鼻腔伸进人的体内，然后用它将金属线圈植入肺部。一切就位以后，金属线圈就会挤压病变组织，让肺上相对健康的部位更自由地呼吸。其他医院也在研究一种小伞状阀门，它能把空气从肺上那些状况欠佳的部位重新引至更健康的部位。 克利夫兰诊所(Cleveland Clnic) 的介入治疗医师阿图尔·C·梅塔(Atul C. Mehta)说：“如果成功了，我们就能帮助大量患者改善生活质量，而且可能以一种无创伤性的方式提高生存率。”克利夫兰诊所是参与了线?治疗试验的医学中心之一。 在欧洲，这种线圈从2008年起就已经获批投入使用。欧洲的一些研究已显示，这种疗法对病人来说很安全，而且能显著改善肺机能、运动能力与生活质量。目前，美国的研究是由加州山景城(Mountainview, Calif.)的RneumRx Inc.公司资助的，该公司是所用线圈的制造商。虽然吸烟者可以在慢性阻塞性肺疾病形成前戒烟来进行预防，但一旦肺部受损，那病情就无法逆转了。大多数患者都是靠使用名为支气管扩张剂的吸入性药物、用氧和肺康复疗法来维持的。 玛丽·摩根(Mary Morgan)是住在俄亥俄州帕尔马(Parma, Ohio)的一名护士。七年前，她被确诊为肺气肿，肺气肿是慢性阻塞性肺疾病的一种表现形式。即便如此，她还是继续抽了好几年烟。因为她说这个病“当时并没有太困扰我”。两年后，55岁的摩根患上了肺炎，还不得不打911急救电话，因为那时她已无法呼吸。虽然她已戒了烟，但是仍需要一直吸氧。她还经常喘气，讲话时一次也说不了几个词。摩根说：“已经病到这个地步了，如此痛苦煎熬，都不想再活下去了。” 摩根在完成了一次肺康复治疗后，于去年12月份获准在克利夫兰诊所接受线圈试验治疗。梅塔医生及另一位肺科专家在她的右肺下部植入了12个小线圈。她术后仅在医院待了一晚便出了院，还称自己几乎是马上就感觉好多了。一个月后的测试显示，她的呼吸状况改善了30%。她仍在补充吸氧并计划本月晚些时候再在左肺植入另外一些线圈。 慢性阻塞性肺疾病包括两种主要的病症，肺气肿和慢性支气管炎，而大多数患者是两者兼具。随着肺气肿的病情加重，它会破坏气?，或称为肺泡——它们负责交换肺部及周遭组织与血流间的空气。肺的病变部位将会过度膨胀、变得没有弹性并滞留空气。于此同时，扩张的气囊也会挤压肺部相对健康的部位。患者可能会感到窒息，而药物治疗则可能失效。 病情更严重的慢性阻塞性肺疾病在美国估计影响到了三、四百万人。梅塔医生预计，多达一百万人可能需要通过手术进行某种形式的肺减容或新型的低创伤线圈疗法。这类手术需要在胸部开一个大切口或几个小切口以切除病变组织。其目的是为了能让病人用余下的、肺上相对健康的部位更容易地呼吸。 10年前进行的一项名为“全国肺气肿治疗试验”(National Emphysema Treatment Trial)的大型研究显示，与药物治疗相比，手术并未显现出会给病患在总体上带来更高的存活率。该研究倒是表明，在有些患者身上，手术疗法更具优势——这些患者的上肺叶病变更严重，他们的运动能力也差。即便如此，这种治疗手段还是用得少之又少。其并发症的患病率也高。而在美国，提供这种疗法的医疗中心也相对较少。 匹兹堡大学医学中心(University of Pittsburgh Medical Center)肺功能与运动生理学实验室(Pulmonary Function and Exercise Physiology Lab)主任、该校部分线圈植入试验的主要研究者弗兰克·休尔巴(Frank Sciurba)说：“我们已经证明，在适合动手术的病人身上，肺减容手术的确有效，但医生们不会将病患送去接受这种疗法，而患者自身也对大手术没什么兴趣。”他还称，试验的目的之一就是确定什么样的患者拥有适应线圈疗法的肺部结构与生理机能，从而能从该疗法中获益。 线圈疗法的相关试验并未探讨成本问题。休尔巴博士说：“长远的希望是，（通过降低住院成本、减少并发症和再入院的情况），该疗法能更划算。”PneumRx公司的一名女发言人称，进行线圈疗法在欧洲需要花费1.5万美元。她还说：“我们尚未深入美国市场，所以还无法作出一个有效的比较。” 而在其他非手术治疗技术方面，专家们已收获了好坏不一的结果，比如用化学密封剂和蒸汽去破坏肺上的病变部位。在目前另一起临床试验中，研究人员牵引一个小伞型阀门进入气道，把空气从肺部欠佳的部位重新导至肺上更为健康的部位，同时让残留空气排出来。早些时候的一次阀门疗法试验因未满足美国食品药物管理局(Food & Drug Administration)的认证要求而收场，但华盛顿州雷德蒙德市(Redmond, Wash.)器具制造商Spiration Inc. 公司现正出资进行一项新试验，以确认这种疗法能否帮助减少肺部过度膨胀并改善肺的整体机能、提高生命的质量。 芝加哥大学(University of Chicago)的支气管镜检主任、医药学助理教授D·凯尔·贺加斯(D. Kyle Hogarth)正带领一队人在进行阀门研究。他说，不管使用什么器具设备，都存在这样一种潜在风险：植入肺部的外来物引发感染。他还说，线圈本身就未设计成可移除的，而阀门，如果有必要，则可以摘除。因为肺气肿对每个患者的肺部影响会因人而异，所以患者在未来有可能既可以进行线圈植入，又可以接受阀门疗法。贺加斯博士说：“这么做是为了治疗不同类型的病症和呼吸问题。” |
|
|
