Chronic Obstructive Lung Disease
Chronic obstructive lung disease, also known as chronic obstructive pulmonary disease (COPD), is a general term for a group of conditions in which there is persistent difficulty in expelling (or exhaling) air from the lungs. COPD commonly refers to two related, progressive diseases of the respiratory system, chronic bronchitis
. Because smoking
is the major cause of both diseases, chronic bronchitis and emphysema often occur together in the same patient.
COPD is one of the fastest-growing health problems. Nearly 16 million people in the United States, 14 million with chronic bronchitis and two million with emphysema, suffer from COPD. COPD is responsible for more than 96,000 deaths annually, making it the fourth leading cause of death
. Although COPD is more common in men than women, the increase in incidence of smoking among women since World War II has produced an increase in deaths from COPD in women. COPD has a large economic impact on the healthcare system and a destructive impact on the lives of patients and their families. Quality of life for a person with COPD decreases as the disease progresses.
In chronic bronchitis, chronic inflammation caused by cigarette smoking results in a narrowing of the openings in the bronchi, the large air tubes of the respiratory system, and interferes with the flow of air. Inflammation also causes the glands that line the bronchi to produce excessive amounts of mucus, further narrowing the airways and blocking airflow. The result is often a chronic cough
that produces sputum (mainly mucus) and shortness of breath
. Cigarette smoke also damages the cilia, small hair-like projections that move bacteria and foreign particles out of the lungs, increasing the risk of infections.
Emphysema is a disease in which cigarette smoke causes an overproduction of the enzyme elastase, one of the immune system's infection-fighting biochemicals. This results in irreversible destruction of a protein in the lung called elastin which is important for maintaining the structure of the walls of the alveoli, the terminal small air sacs of the respiratory system. As the walls of the alveoli rupture, the number of alveoli is reduced and many of those remaining are enlarged, making the lungs of the patient with emphysema less elastic and overinflated. Due to the higher pressure inside the chest that must be developed to force air out of the less-elastic lungs, the bronchioles, small air tubes of the respiratory system, tend to collapse during exhalation. Stale air gets trapped in the air sacs and fresh air cannot be brought in.
Causes and symptoms
There are several important risk factors for COPD:
- Lifestyle. Cigarette smoking is by far the most important risk factor for COPD (80% of all cases). Cigar and pipe smoking can also cause COPD. Air pollution and industrial dusts and fumes are other important risk factors.
- Age. Chronic bronchitis is more common in people over 40 years old; emphysema occurs more often in people 65 years of age and older.
- Socioeconomic class. COPD-related deaths are about twice as high among unskilled and semi-skilled laborers as among professionals.
- Family clustering. It is thought that heredity predisposes people in certain families to the development of COPD when other causes, such as smoking and air pollution, are present.
- Lung infections. Lung infections make all forms of COPD worse.
In the general population, emphysema usually develops in older individuals with a long smoking history. However, there is also a form of emphysema that runs in families. People with this type of emphysema have a hereditary deficiency of a blood component, an enzyme inhibitor called alpha-1-antitrypsin (AAT). This type of emphysema is sometimes called "early onset emphysema" because it can appear when a person is as young as 30 or 40 years old. It is estimated that there are between 75,000 and 150,000 Americans who were born with AAT-deficiency. Of this group, emphysema afflicts an estimated 20,000-40,000 people (1-3% of all cases of emphysema). The risk of developing emphysema for an AAT-deficient individual who also smokes is much greater than for others.
The first symptoms of chronic bronchitis are cough and mucus production. These symptoms resemble a chest cold that lingers on for weeks. Later, shortness of breath develops. Cough, sputum production, and shortness of breath may become worse if a person develops a lung infection. A person with chronic bronchitis may later develop emphysema as well. In emphysema, shortness of breath on exertion is the predominant early symptom. Coughing is usually minor and there is little sputum. As the disease progresses, the shortness of breath occurs with less exertion, and eventually may be present even when at rest. At this point, a sputum-producing cough may also occur. Either chronic bronchitis or emphysema may lead to respiratory failure—a condition in which there occurs a dangerously low level of oxygen or a serious excess of carbon dioxide in the blood.
The first step in diagnosing COPD is a good medical evaluation, including a medical history and a physical examination
of the chest using a stethoscope. In addition, the doctor may request one or more of the following tests:
Pulmonary function test
Using a spirometer, an instrument that measures the air taken into and exhaled from the lungs, the doctor will determine two important values: (1) vital capacity (VC), the largest amount of air expelled after the deepest inhalation, and (2) forced expiratory volume (FEV1), the maximum amount of air expired in one second. The pulmonary function test
can be performed in the doctor's office, but is expensive.
Chest x ray
Chest x rays can detect only about half of the cases of emphysema. Chest x rays are rarely useful for diagnosing chronic bronchitis.
Blood gas levels
Blood may be drawn from an artery (more painful than drawing blood from a vein) to determine the amount of oxygen and carbon dioxide present. Low oxygen and high carbon dioxide levels are often indicative of chronic bronchitis, but not always of emphysema.
Tests for cause of infection
If infection is present, blood and sputum tests may be done to determine the cause of infection.
Many patients with lung disease also develop heart problems. The ECG identifies signs of heart disease.
The precise nature of the patient's condition will determine the type of treatment prescribed for COPD. With a program of complete respiratory care, disability can be minimized, acute episodes prevented, hospitalizations reduced, and some early deaths avoided. On the other hand, no treatment has been shown to slow the progress of the disease, and only oxygen therapy increases survival rate.
Medications frequently prescribed for COPD patients include:
A. Lung cancer. B. Pneumonia. C. Emphysema. D. Phlegm from chronic bronchitis.
(Illustration by Argosy, Inc.)
- Bronchodilators. These agents open narrowed airways and offer significant symptomatic relief for many, but not all, people with COPD. There are three types of bronchodilators: Beta2 agonists, anticholinergic agents, and theophylline and its derivatives. Depending on the specific drug, a bronchodilator may be inhaled, injected, or taken orally.
- Corticosteroids. Corticosteroids, usually inhaled, block inflammation and are most useful for patients with chronic bronchitis with or without emphysema. Steroids are generally not useful in patients who have emphysema.
- Oxygen replacement. Eventually, patients with low blood oxygen levels may need to rely on supplemental oxygen from portable or stationary tanks.
- Antibiotics. Antibiotics are frequently given at the first sign of a respiratory infection, such as increased sputum production or a change in color of sputum from clear to yellow or green.
- Vaccines. To prevent pulmonary infection from viruses and bacteria, people with COPD should be vaccinated against influenza each year at least six weeks before flu season and have a one-time pneumococcal (pneumonia) vaccine.
- Expectorants. These agents help loosen and expel mucus secretions from the airways.
- Diuretics. These drugs are given to prevent excess water retention in patients with associated right heart failure.
- Augmentation therapy (for emphysema due to AAT-deficiency only). Replacement AAT (Prolastin), derived from human blood which has been screened for viruses, is injected weekly or bimonthly for life.
Surgical procedures for emphysema are very rare. They are expensive and often not covered by insurance. The great majority of patients cannot be helped by surgery, and no single procedure is ideal for those who can be helped. In January of 1996, the government temporarily suspended Medicare payments for lung reduction surgery.
- Lung transplantation. Lung transplantation has been successfully employed in some patients with end-stage COPD. In the hands of an experienced team, the one-year survival rate is over 70%.
- Lung volume reduction. These procedures remove 20-30% of severely diseased lung tissue; the remaining parts of the lung are joined together. Mortality rates can be as high as 15% and complication rates are even higher. When the operation is successful, patients report significant improvement in symptoms.
A structured, outpatient pulmonary rehabilitation
program improves functional capacity in certain patients with COPD. Services may include general exercise
training, administration of oxygen and nutritional supplements
, intermittent mechanical ventilatory support, continuous positive airway pressure, relaxation techniques, breathing exercises and techniques (such as pursed lip breathing), and methods for mobilizing and removing secretions.
For both chronic bronchitis and emphysema, alternative practitioners recommend diet and nutritional supplements, a variety of herbal medicines, hydrotherapy
, acupressure and acupuncture
, aromatherapy, homeopathy, and yoga
COPD is a disease that can be treated and controlled, but not cured. Survival of patients with COPD is clearly related to the degree of their lung function when they are diagnosed and the rate at which they lose this function. Overall, the median survival is about 10 years for patients with COPD who have lost approximately two-thirds of their lung function at diagnosis.
Lifestyle modifications that can help prevent COPD, or improve function in COPD patients, include: quitting smoking, avoiding respiratory irritants and infections, avoiding allergens, maintaining good nutrition
, drinking lots of fluids, avoiding excessively low or high temperatures and very high altitudes, maintaining proper weight, and exercising to increase muscle tone.
Cordova, Francis C., and Gerard J. Griner. "Management of Advanced Chronic Obstructive Pulmonary Disease." Comprehensive Therapy 23, no. 6: 413-424.
Lefrak, Stephen S., et al. "Recent Advances in Surgery for Emphysema." Annual Review of Medicine 48: 387-398.
American Association for Respiratory Care. 11030 Ables Lane, Dallas, TX 75229. (214) 243-2272. http://www.aarc.org.
American Lung Association. 1740 Broadway, New York, NY 10019. (800) 586-4872. http://www.lungusa.org.
National Heart, Lung and Blood Institute. P.O. Box 30105, Bethesda, MD 20824-0105. (301) 251-1222. http://www.nhlbi.nih.gov.
National Jewish Medical and Research Center. 1400 Jackson St., Denver, CO 80206. (800) 222-LUNG (Lung Line). http://www.njc.org.
— Terminal air sacs of the respiratory system, where gas (oxygen and carbon dioxide) exchange occurs.
— Large air tubes of the respiratory system.
— Small air tubes of the respiratory system.
— Drugs that open wider the bronchial tubes of the respiratory system.
— A group of hormones that are used as drugs to block inflammation.
— An instrument used by a doctor to perform a breathing test.
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.
persisting for a long time; applied to a morbid state, designating one showing little change or extremely slow progression over a long period.
chronic airflow limitation
(CAL) any pulmonary disorder occurring as a result of increased airway resistance or of decreased elastic recoil; the diseases most often associated are asthma
, chronic bronchitis
, and chronic pulmonary emphysema
. Called also chronic obstructive pulmonary disease
Chronic airflow limitation has the highest morbidity rate of any significant chronic pulmonary disorder in the United States and is the second most common cause of hospital admissions. It is difficult to estimate its exact incidence because most diseases of the respiratory tract are not reportable and there is some confusion in definition of terms related to diseases of this type. However, the Social Security Administration reports that CAL ranked only second to heart disease as the cause of disability in men over the age of 40. The incidence of CAL is increasing and, although not all specific causes are known, factors contributing to its development and affecting its degree of severity have been identified. Heavy cigarette smoking is probably the most important factor, and others are industrial pollution, occupational exposure to irritating inhalants, allergy, autoimmunity, genetic predisposition, and chronic infections.
Prevention is best accomplished through education of the public about the hazards of cigarette smoking and air pollution and the need for early detection and prompt treatment of respiratory disorders that could become chronic in nature. The American Lung Association is particularly interested in education of lay persons in these matters and in the prevention of all types of respiratory disorders. This agency, which has local offices distributed throughout the country, is an excellent source of information about prevention and the latest developments in the treatment of respiratory diseases.
. This is an insidious disease that can develop into advanced lung damage almost before its victim is aware that the condition is serious. The early symptoms are shortness of breath upon exertion, a mild cough (sometimes called “smoker's cough”), which occurs most often in the morning, and easy fatigability that follows even minimal physical effort. Prompt treatment of these symptoms can forestall the more serious effects of extensive lung damage; however, the destruction of lung tissue and bronchial mucosa damage that has already occurred by the time these symptoms appear is irreversible.
As the disease progresses, the symptoms of dyspnea, weakness, and cough become more severe. The patient has difficulty expelling air from the lungs and the cough becomes more productive of thick, tenacious sputum. The patient looks anxious and drawn and may speak in short, hesitant sentences. Symptoms related to disturbances of the respiratory and circulatory systems and acid-base balance
may appear as these complications develop.
. Destructive involvement of respiratory structures and the resultant impairment of circulatory function can produce serious life-threatening complications. Among these are acute respiratory failure, disturbance in the acid-base balance (which can occur either as uncompensated respiratory acidosis
or metabolic alkalosis
), bronchopulmonary infections, cor pulmonale
(the result of increased resistance in pulmonary circulation), pulmonary embolism
(especially if polycythemia is severe), and peptic ulcer
. blood gas analysis
is helpful in evaluating effectiveness of blood gas exchange across alveolar walls. In severe chronic airflow limitation, the PaCO2
level is high while the PaO2
and the SaO2
levels are low.
Treatment and Patient Care
. In general, treatment is concerned with restoring and maintaining existing lung function, relieving symptoms, and planning a program of rehabilitation tailored to accommodate the individual patient's physiologic needs, physical stamina, vocational needs, lifestyle, and personality. Specific measures of patient care are concerned with (1) initial and periodic evaluation of patient status, (2) maintenance of general health as much as possible, (3) prevention and control of infection, (4) improvement of ventilation, and (5) patient education.
Chronic airflow limitation is a disease that has no cure; its chronic nature requires an ongoing program of assessment and long-term care that is planned and revised as the patient's needs dictate. Whatever the patient care setting—acute care facility, out-patient clinic, long-term care facility, or home—the elements of care presented below are essential to the effective management of the condition.
Evaluation. Patient assessment begins with the taking of the patient's history and performing physical examination and lung function tests at the time the diagnosis is established. These measures, along with blood gas analysis at rest and after exercise, provide a baseline for periodic evaluation of the patient's status to determine the progress of the disease and the effectiveness of treatment.
When patients are informed about the purpose of the tests and therapy they are more likely to participate in the planned regimen of care and to become motivated to continue carrying out their responsibilities in the management of their illness. Those who work with the patient should clarify the goals and offer encouragement when they make progress toward those goals, no matter how slight the improvement might be. This implies, of course, that all members of the health care team have an understanding of the disease, the meaning of various test values, and the purpose of each aspect of care.
Maintenance of Health Status.
It is important to communicate to these patients the concept of health status, particularly in regard to their position on the health-illness continuum. They cannot be completely disease-free or restored to their former state of health. They can, however, manage the disease symptoms for periods of time and some may even make progress toward a better state of health. For those patients who continue to deteriorate despite appropriate care, encouragement should be provided to maintain as much function as possible.
Poor appetite and the potential for dehydration are problems commonly associated with pulmonary disease. Purulent sputum, coughing, and fatigue can contribute to loss of interest in eating. Mouth breathing, increased respiratory rate, and frequent expectorating contribute to the loss of fluid.
Frequent oral hygiene and mouth care can help diminish mouth odor and unpleasant taste. A short period of rest just prior to each meal can help overcome the problem of fatigue. Meals should be spaced so that the stomach is not overloaded at any one time; five small meals, rather than three a day, can help avoid overfilling of the stomach and interference with breathing. Postural drainage and similar procedures should not be done on a full stomach, nor should they be scheduled just before a meal. Adequate hydration can be accomplished by an intake of at least 3000 ml of liquid each day. Unless contraindicated, this should include bouillon, fruit juices, and other liquids the patient finds enjoyable and refreshing.
Physical activity may be severely limited by CAL because of inadequate ventilation and decreased circulation. As with all other aspects of patient care, plans to increase exercise tolerance and promote physical activity should be designed according to the patient's cardiopulmonary status. Techniques to promote muscular relaxation and breathing control are the first step, followed by gradual increase in activity as the patient's progress and general physical condition permit.
Adequate rest is essential, but the hazards of immobility
must be avoided, especially in patients who are fearful that any physical activity may precipitate an exhausting episode of coughing and dyspnea. The goal is to provide sufficient rest so that the body's natural restorative processes can work, but to avoid long periods of sleeping and lying in bed during the day.
When the patient's cardiopulmonary condition is such that bed rest is prescribed, care is taken to avoid complete physical inactivity, which will only serve to increase problems of inadequate ventilation and muscle weakness. Proper positioning is essential and should be such that the neck is extended, with the chin well off the chest. Support under the thighs while the patient is supine will release tension on abdominal muscles, thereby facilitating movement of the diaphragm for deep breathing and effective coughing. The arms and hands should also be supported on pillows and positioned away from the sides to allow for maximum lung expansion without elevation of the upper chest. A foot board is placed so as to maintain good posture, promote comfort, and ensure good muscle tone in the legs and feet.
Prevention and Control of Infection. Acute respiratory infection can be fatal in patients with chronic airflow limitation. Chronic infections inflict further damage to the respiratory structures, lead to increased debilitation, and increase the likelihood of severe complications. Both acute and chronic infections produce increased secretions in the air passages, which further restrict the flow of air.
Contact with others who have an upper respiratory infection should be avoided, as should being in large crowds during the season when such infections are common. A high level of resistance should be maintained through good personal hygiene and adequate nutrition. Vaccines to guard against influenza are recommended. Patients should be taught to watch for changes in color and amount of sputum. If a change in sputum or any other symptoms of infection appear, this should be reported.
Improvement of Ventilation.
It is obvious that measures to improve ventilation in the patient with CAL are of primary importance, and perhaps that is why so many ways have been devised to facilitate the flow of air to and from the lungs. Breathing is most difficult during the expiratory phase, making it difficult to remove trapped air and secretions. In addition, the bronchial walls are weakened in patients with emphysema and are subject to collapse. Health status and physical condition at the time the technique is used will affect the choice of method and its effectiveness.
Hydration is considered especially valuable in improvement of ventilation. Inhaled air should be moist so as to thin the secretions for removal and soothe the irritated mucous membranes. This can be accomplished through the use of vaporizers and humidifiers, either for environmental humidification in the patient's room or in conjunction with oxygen therapy and the administration of aerosols. Oral intake of fluids is also important. Bronchodilators, usually in the form of aerosols, sometimes as oral medications, are usually prescribed. The aerosol method of delivery depends on the ability of the patient to breathe deeply so that the medication reaches the lower segments of the respiratory tract.
Controlled deep breathing patterns are especially helpful in emptying the lungs and providing adequate ventilation. The patient with CAL is taught to expand the lower chest and to use the accessory muscles and diaphragm to improve the breathing pattern. Performance of these breathing patterns is important because patients probably are not in the habit of breathing in the most effective manner, making optimum use of remaining pulmonary function. The patient is taught slow, controlled, and steady breathing. Respiratory effort should be concentrated on slow expiratory flow through parted or pursed lips. Pushing the air out of the lungs too forcefully can bring on collapse of the airway structures. During instruction, the caregiver watches for signs of exhaustion and warns against overdoing the deep breathing until the patient has adjusted to it. A correct breathing pattern should be coordinated with all of the patient's daily activities so that it becomes habitual and is done without too much thought.
Effective coughing does not come easily to patients with this condition. They may have experienced too many episodes in which a dry hacking cough has caused exhaustion, increased dyspnea, and prevented removal of tenacious sputum from the air passages. They must be convinced that, when done correctly, coughing can remove mucous plugs and relieve rather than produce dyspnea. Patients should be warned that explosive coughing is not very effective, can damage the airways, and can lead to exhaustion. The objective of coughing is to move secretions upward gradually so that they can be expectorated.Postural drainage
is also valuable in facilitating the removal of mucus from the air passages. The various maneuvers involved in this procedure are designed to take advantage of gravity flow as a means of clearing specified segments of the air passages when normal air flow is not sufficient to move secretions or stimulate the cough reflex. Chest percussion and vibration may be employed during postural drainage to loosen secretions. oxygen therapy
is used as a supportive measure when there is decreased oxygenation of arterial blood. It can be administered to ambulatory patients being cared for at home. Blood gas analysis is an excellent guide in determining the need for initiating oxygen therapy and for monitoring dosage.
Patient Education. As with all chronic diseases that require long-term planning and management, patient education is of primary importance in successful execution of the plan. Each of the measures previously described involves instruction of the patient and family, particularly when care is carried out on an outpatient basis. The patient should be told why it is necessary to stop smoking, avoid other irritating inhalants, carry out good health practices, take medication only as prescribed, and faithfully perform techniques to improve ventilation. Those patients who follow the exercises prescribed for them often find they can lead more active lives than formerly. Exertional dyspnea becomes less severe and complications from infections caused by bacteria in secretions formerly trapped in the respiratory tract are less frequent. Active participation in a program of self-care gives these patients a sense of control and improves their self-esteem.
chronic fatigue syndrome (chronic fatigue and immunodeficiency syndrome) persistent debilitating fatigue of recent onset, with reduction of physical activity to less than half of usual, accompanied by some combination of muscle weakness, sore throat, mild fever, tender lymph nodes, headaches, and depression, with the symptoms not attributable to any other known causes. Its nature is controversial; viral infection (including Epstein-Barr virus and human herpesvirus-6) may be associated with it, but no causal relationship has been demonstrated. A number of names have been used for this syndrome, including Iceland disease and benign myalgic encephalomyelitis.
chronic granulomatous disease chronic suppurative lymphadenitis, eczematoid dermatitis, enlargement of the liver and spleen, and chronic pulmonary disease associated with a genetically determined defect in the intracellular bactericidal function of leukocytes.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.