COPD (Chronic Obstructive Pulmonary Disease)

COPD (Chronic Obstructive Pulmonary Disease)

Chronic Obstructive Pulmonary Disease (COPD)


Chronic obstructive pulmonary disease is persistent obstruction of the airways occurring with emphysema, chronic bronchitis or both disorders.
  • COPD leads to chronic airflow obstruction which is defined as the persistent decrease in the rate of airflow through the lungs when the person breathes out or exhales.
  • Both emphysema and chronic bronchitis contribute to the to the airflow obstruction of COPD.
    • Emphysema is an irreversible enlargement of many of 300 million air sacs, also known as alveoli that make up the lungs and the destruction of the air sac walls.
    • Chronic bronchitis is characterized by a cough that produces sputum for 3 months or more during 2 successive years. And this cough is not due to other lung diseases.
  • The small airways of the lungs are normally held open by their alveolar wall attachments.
    • In emphysema, the destruction of alveolar wall attachments results in the collapse of the small airways, causing permanent airflow obstruction.
    • In chronic bronchitis, the glands lining the bronchi enlarge, causing increased secretion of mucus.
  • Inflammation of the small airways or bronchioles develops and causes smooth muscle spasm and blockage by secretions.
  • Asthma is also characterized by airflow obstruction.
    • However, in contrast with airflow obstruction of COPD, the airflow obstruction of asthma is completely reversible in most people, either spontaneously or with treatment.
  • The airflow obstruction of COPD leads to an increase in the effort required for a person to breathe.
    • The obstruction causes air to become trapped in the lungs, so that the amount of air remaining in the lungs after a full exhalation is increased.
    • The number of capillaries in the walls of the alveoli decreases.
    • These abnormalities impair the exchange of oxygen and carbon dioxide between the alveoli and the blood.
    • In the earlier stages of COPD, oxygen levels in the blood are decreased but carbon dioxide levels remain normal.
    • In the later stages, carbon dioxide levels increase and oxygen levels fall even further.
  • The decrease in oxygen levels in the blood stimulates the bone marrow to send more red blood cells (RBC) into the bloodstream. This condition is known as secondary polycythemia.

Some numbers and facts on COPD

  • In the United States, about 16 million people suffer from the chronic obstructive pulmonary disease.
  • It is second only to heart disease as a cause of disability that forces people to stop working.
  • It is the fourth most common cause of death, accounting for more than 1,00,000 deaths per year in the United States.
  • The number of deaths from COPD has increased by 40% over the last 2 decades.
  • More than 95% of all deaths from COPD occur in people older than age 55.
  • COPD affects men more than that of the women. Also, it is more fatal in men. There has been a recent increase in the rate of deaths in women.
  • COPD is also more often fatal in whites than in non-whites and in blue-collar workers than in white-collar workers.
  • The prevalence of COPD in the United Kingdom is estimated to be between 1% to 2%, but the actual number is much higher since the airflow limitation is present in more than 10% of the general population.
  • About 10% of the people hospitalized in the UK are due to exacerbations of COPD.
  • It is also the sixth most common cause of death in the UK, accounting for 30000 deaths per year.
  • In recent years, COPD has gained global importance, largely due to increased tobacco consumption in the developing countries (in the form of cigarettes). The situation is alarming because if this trend continues, it will be the third largest cause of death and the fifth largest cause of disability or adjusted life in the very near future, probably in the next 3 to 5 years (estimated).


  • Cigarette smoking
    • The most important cause of COPD.
    • About 15 to 20% of smokers develop this disease.
    • Pipe and cigar smokers develop COPD more often than nonsmokers but not as often as cigarette smokers.
    • With age, susceptible cigarette smokers lose lung function more rapidly than nonsmokers.
    • If a person stops smoking, there is little improvement in lung function.
    • However, the rate of decline of lung function does return to that of nonsmokers when the person stops smoking, thus delaying the progression of symptoms.
  • Heredity
    • COPD tends to occur more in some families. Hence, there may be an inherited tendency.
  • Occupational
    • Working in an environment polluted by chemical fumes or dust may increase the risk of COPD.
  • Others
    • Exposure to air pollution and smoke from nearby cigarette smokers worsen a person’s COPD and may cause COPD.
  • Alpha1-antitrypsin deficiency
    • This is a rare hereditary condition in which the body produces a markedly decreased amount of the protein – alpha1-antitrypsin.
    • The main role of this protein is to prevent neutrophil elastase from damaging the alveoli.
    • Consequently, emphysema develops by early middle age in people with severe alpha1-antitrypsin deficiency.

Risk Factors

  • Tobacco smoking
    • Cigarette smoking
    • Pipe smoking
    • Cigar smoking
  • Cannabis smoking
  • Biomass solid fuel fires
  • Occupational
    • Workers who work in coal mines
    • Workers who work with cadmium
  • Pollution
    • Outdoor pollution
      • Example: pollution caused by traffic jams or industrial pollution in developing countries
      • Example: exposure to chemical fumes
    • Indoor pollution
      • Example: working in closed offices with impaired quality of air
      • Example: exposure to dust
    • Low socioeconomic status
    • Low birth weight
    • Lung growth defect due to:
      • Childhood infection
      • Maternal smoking
    • Infections
      • Recurrent infection
      • Persistence of adenovirus in lung tissue
      • HIV infection associated with emphysema
    • Airway hyper activity
    • Genetic factors
      • Alpha1-antitrypsin deficiency
    • Age


  • In a person with COPD, a mild cough that produces clear sputum develops by around age 45, usually when the person first gets out of the bed in the morning.
  • Cough and sputum production persists for the next 10 years.
  • Shortness of breath may be noted with exertion.
  • Sometimes, shortness of breath is first noted only with a lung infection, during which time the person cough more and has an increased amount of sputum.
  • The color of the sputum changes from clear to yellow or green.
  • By the time, the person reaches to his middle or late 60s, especially with continued smoking, shortness of breath with exertion becomes more troublesome.
  • A lung infection may result in severe shortness of breath even when the person is at res and may require hospitalization.
  • Shortness of breath during activities of daily living such as washing, dressing, toileting, sexual activity, etc. may persist after the person has recovered from the lung infection.
  • About one-third of people with COPD experience severe weight loss, in part because shortness of breath makes eating difficult and in part because of the increased levels of tumor necrosis factor in the blood.
  • Swelling of the leg often develops which may be due to cor pulmonale.
  • People with COPD may intermittently cough up blood, which is usually due to the inflammation of the bronchi, but which always raises the concern of lung cancer.
  • Morning headaches may occur because breathing decreases during sleep, which causes increased retention of the carbon dioxide.
  • As COPD progresses, some people, especially those who have emphysema develop unusual breathing patterns.
  • Some people breathe out through pursed lips. Others find it more comfortable to stand over a table with their arms outstretched and weight on their palms, a maneuver that improves the function of the diaphragm.
  • Over the time, many people develop barrel chest as the size of the lungs increases because of the trapped air.
  • Low oxygen levels in the blood can give a blue tint to the skin. This condition is known as cyanosis.
  • Clubbing of the fingers is rare and raises the suspicion of lung cancer.
  • Fragile areas in the lungs may rupture, permitting the air in the lungs to leak into the pleural space. This condition is known as pneumothorax.
    • This condition often causes sudden pain and shortness of breath and requires immediate intervention by a doctor to evacuate the air from the pleural space.
  • Symptoms may suddenly worsen during the flare-ups of COPD.
    • A flare-up is a worsening of symptoms of a cough, increased sputum and shortness of breath.
    • Sputum color changes from white to yellow or green and fever and body ache sometimes occur.
    • Shortness of breath may be present when the person is at rest and may be severe enough to require hospitalization.
    • Severe air pollution, common allergens and viral and bacterial infection can cause flare-ups.


  • Chronic bronchitis is diagnosed by the history of a prolonged cough.
  • Emphysema is diagnosed by the combined findings observed during a physical examination and on pulmonary function test results. However, by the time the doctor notices these abnormalities, emphysema is moderately severe.
  • It is not important for doctors to differentiate between chronic bronchitis and emphysema, but it is important for them to determine how a person feels and functions as it indicates the severity of airflow obstruction.
  • In mild COPD, a doctor may find nothing during a physical examination.
    • As the disease progresses, wheezes may be hard through the stethoscope, and prolonged expiration and decreased breathing sounds become apparent.
    • Chest movement diminishes during breathing and the use of neck and shoulder muscles in breathing may be noticed.
    • In mild COPD, results of a chest X-ray are usually normal.
    • As COPD worsens, the chest shows over inflation of the lungs; decreased shadows of the blood vessels denote the presence of emphysema.
  • Doctors can evaluate airflow obstruction with forced expiratory spirometry.
    • The decrease in forced expiratory volume in 1 second (FEV 1) and the ratio of FEV 1 to FVC (forced vital capacity) are required to demonstrate airflow obstruction and to make the diagnosis.
  • A blood test may show abnormally high levels of red blood cells (RBCs) or polycythemia.
  • Pulse oximetry or a sample of blood taken from an artery often show low levels of oxygen.
  • High levels of carbon dioxide in the arteries are seen late in the course of the disease.
  • If a person develops COPD at a young age, especially when the person has a family history of COPD, the blood levels of alpha1-antitrypsin is measured to determine whether the person has alpha1-antitrypsin deficiency.
    • This genetic disorder is also suspected when COPD develops in someone who has never smoked.


Quit Smoking

  • The most important treatment for COPD is to stop smoking.
  • The patient should be encouraged, advised and assisted to quit smoking. Also, every possible attempt should be made to explain to the patient about the role of smoking in the development and the progression of the disease.
  • Quitting smoking when the airflow obstruction is mild to moderate, a person experiences following improvements:
    • Often improves cough
    • Reduces the amount of sputum, and
    • Slows the development of shortness of breath
  • Stopping smoking at any point in the disease process provides benefit.

Avoiding Exposure

  • The person should try to avoid exposure to airborne irritants including secondhand smoke and air pollutants.
  • Wearing a pollution mask, especially for people with COPD in developing or third world countries will help in slowing the progression of the disease.


  • If a person with COPD contracts influenza or pneumonia, COPD may worsen markedly.
  • Hence, a person with COPD should receive an influenza vaccination every year and pneumococcal vaccination every 5 years after an initial pneumococcal vaccination.

Treatment of Symptoms

  • Wheezing and shortness of breath are relieved when airflow obstruction improves.
  • Although the airflow obstruction due to emphysema is not reversible, bronchial smooth muscle spasm, inflammation, and increased secretions are potentially reversible.
  • Anticholinergic drugs
    • Ipratropium given by metered-dose inhales, 4 times a day, is the drug of choice to relieve the shortness of breath.
  • Beta-adrenergic agonists
    • When symptoms are more severe, inhaled beta-adrenergic agonists, such as albuterol, more rapidly relieves shortness of breath than ipratropium.
    • Salmeterol – a long-acting beta-adrenergic agonist with a delayed onset of action, can be given by inhalation every 12 hours.
      • This drug is useful for prolonged relief of symptoms in some people, especially at night.
    • The combination of ipratropium and albuterol in a metered-dose inhaler has the advantage of decreasing the number of inhalers the person must use.
    • People who have difficulty using metered dose inhalers benefit by inhaling the drug from a delivery device called a spacer.
    • Solutions of ipratropium and beta-adrenergic agonists may also be given using nebulizers. This mode of therapy is reserved for people who have severe disease.
      • A nebulizer creates a mist of drug and its use does not have to be coordinated with breathing.
      • Nebulizers today, are more portable than they were in past.
      • Some units can even be plugged into a cigarette lighter in a car.
    • Beta-adrenergic agonists are rarely given by mouth for people with COPD because they tend to work slower than the inhaled form and are more likely to cause side effects, including abnormal heart rhythms.
    • Theophylline acts by a different mechanism than ipratropium and beta-adrenergic agonists.
      • It is given only to those people who do not respond to other drugs.
      • The drawback of oral theophylline therapy is its side effects:
        • Unpredictable metabolism
        • Drug interactions
      • The dose must be carefully controlled by the doctor and levels of the drug in the blood must be measured periodically.
      • A long-acting drug permits twice daily dosing in many people and help to control shortness of breath at night.
    • Bronchodilators
      • Bronchodilators are essential in the management of breathlessness.
      • Inhaled bronchodilators are preferred and various types of devices are available to deliver these drugs to the lungs.
      • Short-acting bronchodilators
        • These are useful in patients with mild disease.
      • Long-acting bronchodilators
        • These are useful in patients with moderate to severe form of the disease.
      • Oral bronchodilators are used in patients who cannot use inhalation devices.
      • Theophylline is one such drug (please read above to know more on theophylline’s use in COPD).
      • Bambuterol is also used on certain occasions.
        • It’s a pro-drug of terbutaline.
      • Corticosteroids
        • These drugs are helpful for many people with moderate and severe COPD whose symptoms cannot be controlled by other drugs.
        • Inhaled corticosteroids do not prevent the decline of lung function over time. Also, these are preferred in patients with severe disease (FEV1 < 50%) as they are effective in reducing the frequency and severity of exacerbations.
        • However, their use improves the symptoms and results in a decreased frequency of COPD flare-ups.
        • Because of the local delivery of drugs to the lungs, inhaled corticosteroids produce fewer side effects than treatment given by mouth.
        • However, higher doses of inhaled corticosteroids can have effects throughout the body such as worsening of osteoporosis.
        • Corticosteroids given by mouth are largely restricted to treatment of COPD flare-ups or are given to people who continue to have symptoms from airflow obstruction and who are not responding to a simpler regimen.
        • The combined use of inhaled corticosteroids with beta2-agonists produces a marked improvement in breathlessness and reduces the severity and the frequency of exacerbations.
        • Oral corticosteroids, though useful during exacerbations; but when employed in maintenance therapy leads to osteoporosis and impaired skeletal muscle functions.
      • There is no reliable therapy for thinning secretions so they can be coughed up more easily.
        • However, avoiding dehydration may prevent thick secretions.
        • A rule of thumb is to drink enough fluids to keep the urine pale except for that passed first in the morning.
      • In severe COPD, respiratory therapy may help loosen secretions in the chest.
      • A doctor often uses spirometry and pulse oximetry during treatment to monitor the person’s symptoms.
      • Arterial blood gas measurements add information that is useful in severe disease.

Treatment of Flare-ups

  • Flare-ups should be treated by the doctor as soon as possible.
  • If treatment fails, hospitalization may be needed.
  • When a bacterial infection is suspected by the doctor, 7 to 10 days of antibiotic treatment is often prescribed.
  • Many doctors give people who have COPD a supply of antibiotics and advise them to start taking the drug early in a flare-up.
  • A number of antibiotics can be taken by mouth, including trimethoprim-sulfamethoxazole, doxycycline, amoxicillin-clavulanic acid and ampicillin.
  • Many doctors reserve the newer antibiotics for more severe lung infections or for people in whom treatment with the older and less expensive drugs has not worked.
  • Although many people with COPD think that they should not take antibiotics to prevent flare-ups, there is no indication that these drugs prevent flare-ups.
  • Sometimes corticosteroids are given by mouth for 10 to 14 days to help reduce the severity and length of flare-ups.

Oxygen Therapy

  • Long-term oxygen therapy prolongs the life of people who have advanced COPD and severely reduced oxygen levels in the blood.
  • Although, round the clock therapy is best, using oxygen 12 hours a day also has some benefits.
  • This therapy is effective in:
    • Reducing the red blood cells caused by low blood oxygen levels
    • Improves mental functioning
    • Helps to relieve heart failure caused by COPD
  • Oxygen therapy may also improve shortness of breath during exercise.
  • Different devices are available for oxygen therapy.
    • Electrically driven oxygen concentrators are used mainly for people who are home-bound.
    • The use of compressed oxygen in small tanks permits short periods outside the home for such people.
    • Liquid oxygen systems are expensive but are preferable for people who are active.
      • These systems permit several hours away from the source reservoir by use of portable liquid oxygen containers.
    • People should never use oxygen therapy near open flames or while smoking.

Pulmonary Rehabilitation

  • Pulmonary rehabilitation is a program designed for people who have chronic lung disease.
  • The primary goal of the person enrolled is to achieve and maintain the maximum level of independence and functioning.
  • Pulmonary rehabilitation can help people who have COPD.
    • However, lung function does not improve with pulmonary rehabilitation.
  • It is also beneficial for people with other lung disorders.
  • All age groups can benefit from this program, including the ones who are older than 70.
  • These rehabilitation programs consist of a combination of:
    • Enrollment and goal setting
    • Education about the disease
    • Exercise training
    • Nutritional evaluation and counseling
    • Psychosocial counseling
    • Drug use and education
    • Information on oxygen therapy
    • Chest physical therapy
    • Postural drainage
    • Suctioning
    • Breathing exercises
  • These programs have been found to be effective in:
    • Improving a person’s independence
    • Improving the quality of life
    • Decrease the frequency of hospital visits
    • Decrease the length of hospital stays
    • Improving the person’s ability to exercise
  • Exercising programs can be carried out in the clinic and at the home.
  • Some of these exercises are mentioned below:
    • Exercises for the legs:
      • Stationary bicycling
      • Stair climbing
      • Walking
    • Exercise for the arms:
      • Weightlifting
    • Oxygen is often recommended during the exercise.
    • The only drawback of exercising programs is that gains that are achieved by exercise, is quickly lost if a person stops exercising. This is a common drawback for any exercise program.
    • Special techniques are taught for decreasing shortness of breath during activities such as cooking. Engaging in hobbies and sexual activity.

Surgical Intervention

  • Lung volume reduction
    • This is an experimental surgery and it can be carried out in people who have severe emphysema in the upper portions of their lungs.
    • In this operation, the most severely diseased portion of the lungs is removed.
    • As a result, this permits the remaining portion of the lungs and the diaphragm to function better.
    • It is not known how long the improvement lasts.
    • People are required to stop smoking for at least 6 months before the surgery.
    • They should also undergo an intense rehabilitation program to be certain lung function has improved significantly before undertaking this operation, which carries a mortality rate of about 5 to 8%.
  • Bullectomy
    • Young patients who have minimal airflow limitation and with a lack of generalized emphysema are considered for this surgery only if:
      • Large bullae are compressing the surrounding normal lung tissue.

Other Treatments

  • In case of people with a severe alpha1-antitrypsin deficiency, the missing protein can be replaced.
  • The treatment which requires weekly intravenous infusions of protein is an expensive one.
  • For people who are younger than 55, single lung transplantation can be considered.
    • This treatment option poses certain challenges like:
      • Finding the donor
      • Matching the organ
      • Cost of surgery
      • Time taken during the legal procedure in preparing the organ donation documents and getting them approved from the concerned government agencies.

Prognosis and the end of life issues

  • The prognosis for people with mild COPD is favorable, little worse than the prognosis for smokers without COPD.
  • Continued smoking assures that the symptoms will worsen.
  • With moderate and severe airway obstruction, the prognosis becomes progressively worse.
  • People with an FEV1 (forced expiratory volume in 1 second) between 35 and 50% of normal are still only more likely to die within 10 years than a normal person.
  • About 30% of people with more severe airway obstruction die in 1 year and 95% people die in 10 years.
  • Death may result from:
    • Respiratory failure
    • Pneumonia
    • Pneumothorax
    • Heart rhythm abnormalities (arrhythmias)
    • Blockage of the arteries leading to the lungs (pulmonary embolism)
  • People with COPD have a high risk of lung cancer beyond that due to their use of cigarettes.
  • People in advanced stages of COPD are likely to need more help with medical care and with activities of daily living.
  • People with end-stage disease who develop flare-ups may need an endotracheal tube and mechanical ventilation.
    • The period of mechanical ventilation may be prolonged and some people remain ventilator-dependent.
    • Mechanical ventilation can be life-saving whenever people are not able to move enough air in and out of their lungs.
    • A plastic tube is inserted through the nose or through the mouth into the trachea. This tube is attached to a machine that forces air into the lungs.
    • Exhalation occurs passively because of the elastic recoil of the lungs.
  • It is important for people to consider with their doctors and loved ones whether or not they wish this kind of supportive therapy.
    • The problems with this therapy are:
      • A person becomes bed bound to a more or less extent.
      • Treatment is expensive
      • Another person is required to look after the patient on ventilation.
    • The best way of assuring that a person’s wish or wishes are carried out is to have completed an advanced directive.
    • A health care proxy should also be preferably appointed.

Additional Information for Healthcare Professionals


  • COPD has systemic and pulmonary components.
  • Enhanced secretion of airway mucus manifests as bronchitis. This increase in mucus secretion is due to:
    • Enlargement of mucus-secreting glands
    • Increased number of goblet cells in the larger airways
  • Limitation in the airflow is due to:
    • Loss of elastic tissue surrounding the smaller airways
    • Inflammation and fibrosis in the airway wall
    • Mucus accumulation in the airway lumen
  • This limitation in the airflow is further enhanced by cholinergic tone.
  • The decrease in pulmonary and chest wall compliance is gas trapping and hyperinflation; both of which happens due to premature airway closure.
  • Progressive hyperinflation which occurs during the exercise. is mainly due to the shortening of the time available for expiration.
  • Dead space volume increases and maximal sustainable ventilation is reduced due to increased V/Q mismatch.
  • The respiratory muscles are at a  mechanical disadvantage because of the increased horizontal alignment of the intercostal muscles and the flattening of the diaphragmatic muscles. As a result of this, the work of the breathing is considerably increased; initially at exercise and later at rest with the advancement of the disease.
  • The destruction of the alveoli and the appearance of emphysema occurs in the alveolar capillary units due to the unopposed action of proteases and oxidants.
  • Emphysema can be classified as:
    • Periacinar
    • Panacinar
    • Centriacinar
  • This classification of the emphysema is based on the pattern of enlarges air spaces.
  • Impaired gas exchange and respiratory failure occur in some individuals due to the formation of the bullae.

Clinical Features

  • Chronic Obstructive Pulmonary Disease (COPD) should be suspected in following patients:
    • Patients who are over 40 years of age with the following symptoms:
      • A persistent cough
      • Sputum production
      • Breathlessness
  • Based on the symptoms and other clinical features, the diagnosis should be done to differentiate COPD with the following diseases:
    • Asthma
    • Bronchiectasis
    • Tuberculosis
    • Congestive cardiac failure
  • Chronic severe asthma is difficult to differentiate from COPD on the basis of symptoms and other presentations.
  • A cough is the first symptom.
  • Small amounts of mucoid sputum accompanied by a cough is a characteristic symptom of COPD.
  • The occurrence of a cough and sputum on most days for at least 3 consecutive months at least 2 successive years is a characteristic symptom of chronic bronchitis.
  • Exacerbations of COPD may get complicated by hemoptysis, but this alone is not conclusive of COPD unless it is confirmed by thorough investigations.
  • Breathlessness is the first complaint that a patient tells the doctor. The extent of breathlessness should be quantified using scales such as the modified MRC dyspnoea scale (see the table below). These values can be used as a reference when the disease progresses in the future.
  • In the follow-up visits of the patients or in the advanced stage of the disease, the patient should be enquired/examined for the presence of edema and morning headaches. These conditions are indicative of hypercapnia.
  • Healthcare professional should not rely on the physical signs for a conclusive diagnosis of COPD since these signs are:
    • Non-specific
    • Correlate poorly with lung functions
    • Seldom obvious until the disease is advanced
  • Pitting edema and Body Mass Indes (BMI) should be recorded and documented.
  • Infection is usually accompanied by crackles. But if it is persistent, there is a possibility of bronchiectasis.
  • A physician should get alert on the occurrence of finger clubbing. Though it can occur in COPD, it is not an exclusive characteristic of COPD. There could be a possibility of a more serious pathology.
  • Classically, there are 2 types of COPD patients:
    • Pink puffers
      • Are usually thin built
      • Breathless
      • Maintains a normal PaCO2 until the late stage of the disease
    • Blue bloaters
      • Develops hypercapnia earlier
      • Develops edema
      • Develops secondary polycythemia
  • Practically, most of the patients of COPD usually represents a combination of the 2 types mentioned above.

Modified MRC dyspnoea scale

GradeDegree of breathlessness related to activities
0No breathlessness except with strenuous exercise.
1Breathlessness when hurrying on the level or walking up a slight hill.
2Walks slower than contemporaries on level ground because of breathlessness or has to stop for breath when walking at own pace.
3Stops for breath after walking about 100 m or after a few minutes on level ground.
4Too breathless to leave the house or breathless when dressing or undressing.

Assessment of severity of airflow obstruction according to FEV1 as a percentage of predicted value

Mild50 – 80% predicted.
Moderate30 – 49% predicted.
Severe<30% predicted


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