COPD

Emphysema

March 27, 2019

What Is Emphysema?

肺气肿是A.肺部疾病导致肺组织的破坏和肺泡（气囊）的不可逆扩大，从而从血液中除去二氧化碳。由于肺泡的墙壁变得逐渐扩大，它们失去弹性，并且在呼气期间减少了在肺部出肺的能力。结果，受影响的空气囊在启发期间无法正确填充新鲜空气，并且氧气之间的氧气和二氧化碳的交换变为损害。这导致呼吸急促表征肺气肿。

Along with chronic bronchitis, emphysema is one of the primary lung disorders that constitutes chronic obstructive pulmonary disease, or COPD

The onset of emphysema is gradual, with symptoms typically developing after age 50; however, irreversible lung damage may occur long before symptoms become severe enough to warrant medical attention. Such damage is initiated by smoking or other lung irritants, which lead to the destruction of lung tissue.

The prognosis for patients who have emphysema varies, depending on the severity of the condition and whether or not the patient continues to smoke. Although the disease is progressive and irreversible, patients who stop smoking and receive oxygen therapy generally have a longer life expectancy.

谁得到了呼气肿？

According to the American Lung Association, more than 3.1 million people in the United States have been diagnosed with emphysema. Emphysema and other types of COPD are the fourth leading cause for death in the United States. The condition occurs slightly more often in men (about 52 percent of cases) than women; however, the mortality rate is higher in women. Emphysema is more common in Caucasians than African Americans.

More than 90 percent of patients who have emphysema are over the age of 45 at the time of diagnosis. The disease is most common between the ages of 60 and 80.

大约100,000人在美国的遗传形式的含有α-1抗酸胰蛋白缺乏症的肺气肿或家族性肺气肿。这种疾病，北欧血统人民更常见，往往会导致32和40岁之间的症状。

Symptoms

Shortness of breath.
Wheezing. 
咳嗽（湿或干）。
Fatigue.
减肥。
Barrel-chested appearance.
Cyanosis (bluish tint to the lips, fingertips, and skin; caused by low levels of oxygen[O2]in the blood).
水肿（肿胀;通常在脚和脚踝处）。
Headaches (especially upon waking in the morning as a result of low oxygen levels during sleep).

What If You Do Nothing?

如果肺气肿未经治疗，特别是患者继续吸烟，症状会恶化。此外，肺气肿可以导致许多并发症包括：

Cor pulmonale (pulmonary hypertension and right-sided heart failure)
心脏衰竭
Pneumonia and other lung infections
Pneumothorax (collection of air within the membrane that surrounds the lungs[pleural space]的）
Polycythemia (excess red blood cell production that occurs in response to low oxygen levels in the blood; can block small blood vessels)
呼吸衰竭

Causes/Risk Factors

Smoking is the leading cause of emphysema. Up to 85 percent of emphysema cases develop in longtime cigarette smokers. 
长期暴露于肺刺激剂，例如工业烟雾和灰尘，并且在空气质量差的地区生活是与肺气肿的发展相关的其他因素。
由于遗传性缺乏α-1-抗抗酸酯（AAT），也可能发生肺气肿。这种酶通常阻碍肺部的组织破坏。罕见的个体缺少这种酶可以在休息时期发育肺气肿，即使他们不吸烟。

诊断

为了诊断肺气肿，医生采取完整的患者和家庭病史并进行体检。如果这些建议诊断肺气肿，则可以进行诊断测试。

用于诊断肺气肿的测试包括以下内容：

血液测试(e.g., complete blood cell count[CBC]，动脉血气[ABG])。血液测试可以用来排除其他赖斯tions and can identify individuals with alpha-1-antitrypsin deficiency. Arterial blood gas measures levels of oxygen and carbon dioxide in the blood and can be used to determine if oxygen therapy is needed.
Imaging tests(e.g., chest x-ray, computed tomography[CT scan])。A chest x-ray or CT scan will likely be required to demonstrate the lung damage that distinguishes emphysema from other forms of lung disease.
Oximetry（非侵入方法测量血液中氧水平）。称为脉冲血氧计的电子设备连接到主体的一部分（例如，指尖，耳瓣，额头），并用于测量血液中的氧气（O2）水平。
Pulmonary function tests（例如，峰流动，肺活量测定）。肺功能试验（PFT）用于测量肺内的空气流量并评估肺功能。也可以进行肺部卷测试以测量肺容量和功能。

Treatment

肺气肿是一种不可逆转的条件，治疗的目标是减少症状并减缓疾病的进展。最重要的一步是戒烟。戒烟可以大大减缓肺功能下降。

肺气肿治疗可包括以下内容：

Medications。There are a number of different types of medications that can be used to treat emphysema. Some types are inhaled (e.g., through an inhaler or a nebulizer), and others are taken orally (e.g., in pill form).
Inhalers and nebulizers deliver medication directly into the lungs, which can result in fewer side effects; however, if these devices are used incorrectly, the medication may be ineffective. A spacer device is a tube that can be used with an inhaler to help patients take the medication correctly.
支气管扩张剂（例如，抗胆碱剂，β激动剂，茶碱）可用于治疗急性加剧（称为短作用药物）或防止症状恶化（称为长效药物）。抗生素（例如，二十霉素，十二胞环素）通常用于治疗导致急性发作的感染;抗炎药（例如，类固醇[prednisone]）可用于减少肺炎。
具有家族性肺气肿的患者（α-1抗催害患者缺乏肺气肿）可以用α-1蛋白酶抑制剂（例如，甲状腺，吡啶蛋白）处理，其通常静脉内（即通过静脉）施用。在输注之前，患者可以给予其他药物以降低过敏反应的风险。
Oxygen therapy。Oxygen therapy often is necessary to treat advanced cases of emphysema. In most cases, oxygen (O2) is delivered through a small tube (called a nasal cannula) from an oxygen tank to the patient's nose. Some patients require extra oxygen while walking, exercising, or sleeping, and others require it continuously. Portable oxygen units also are available.
Pulmonary rehabilitation。This treatment, performed by a multidisciplinary team including respiratory therapists, physical and occupational therapists, other healthcare professionals, strives to help the patient become more physically active, become more educated about their disease and treatment options, and generally reduce disability from the disease. Respiratory therapists may help educate the patient and make sure medical equipment is functioning properly, adjust settings as instructed by a physician, and instruct patients in the correct use of the equipment. Physical and occupational therapists assist patients with special exercises that train muscles used for breathing and nutritionists may help patients with developing a plan on eating appropriately and maintaining a healthy weight.
手术。手术可用于治疗精选患者中的肺气肿。手术类型包括肺还原手术（涉及除去肺组织的受损区域，以允许健康组织更有效地发挥作用）和肺移植手术（仅在选择末期疾病的患者中考虑）。具有晚期疾病的患者患有手术并发症的风险增加，包括死亡。

预防

Avoiding exposure to cigarette smoke is the most effective way to prevent developing emphysema. And while nearly all smokers suffer some lung damage, quitting smoking can prevent further lung deterioration.

保持健康的生活方式（例如，定期锻炼，妥善饮食），避免暴露于空气污染和二手烟，并接受呼吸道感染的及时治疗也可以帮助预防肺气肿。