Suspecting COPD

COPD can be suspected in most patients on the basis of symptoms and signs.³² Alternate diagnosis such as bronchial asthma, pulmonary tuberculosis, bronchiectasis, malignancies and other chronic lung diseases may require exclusion. Investigations would be required to confirm the diagnosis.

Clinical history

Diagnosis is considered in any individual who presents with characteristic symptoms and presence of one or more risk factors. The important clinical indicators are as follows:

1. Chronic cough: Present on most days for at least 3 months in a year for 2 or more consecutive years.³³ Cough may be either present throughout the day or only intermittently. Cough is sometimes nocturnal in nature.

2. Chronic sputum production: Cough may or may not be associated with production of mucoid or mucopurulent sputum. Both cough and sputum productions are characteristically more in the early morning, on waking up.

3. Breathlessness (dyspnoea): Dyspnoea may not be present initially, but develops later in the course. It is progressive over the time. Dyspnoea is worse on exercise and during acute exacerbations.

4. Acute exacerbations: There are repeated episodes of acute bronchitis causing worsening of symptoms. Most patients would seek medical help only during these episodes of worsening.

5. Risk factors: History of tobacco smoking is present in most male patients. Nonsmoker patients (especially women) are significantly exposed to other risk factors such as the combustion of solid fuels or occupational exposures to dusts and fumes.

Physical examination

Though an important component of clinical assessment, physical examination is rarely diagnostic in COPD.³⁴ Physical signs of airflow limitation are rarely present until significant impairment of lung function has occurred. However, certain findings on clinical examination point towards the diagnosis of COPD.³⁵

The chest examination may reveal signs of emphysema such as the barrel shape (increased anteroposterior diameter, more horizontally set ribs, prominent sternal angle and wide subcostal angle). Due to the elevation of sternum, the distance between the suprasternal notch and the cricoid cartilage is reduced from the normal 3-4 fingerbreadths. The patient may use accessory muscles of respiration.

Chest percussion will reveal findings of hyperinflation with obliteration of cardiac dullness and downward displaced upper border of liver dullness. Elsewhere, the note will be hyperresonant. Breath sounds will have a prolonged expiratory phase with a uniformly diminished intensity. Fine inspiratory crepitations and rhonchi are commonly heard. Forced expiratory time (FET) will be prolonged to more than 6 seconds and patient may have pursed lip breathing.³⁶

The physical findings may change in the presence of complications.

Alternate diagnosis

Asthma is generally excluded on the basis of history. It is usually present from childhood and is characterized by episodes of breathlessness and wheezing with asymptomatic periods in between. Rhonchi are more prominent and extensive on physical examination. More importantly, there is greater variability and reversibility of symptoms, physical signs and tests of airway obstruction in asthma than COPD.

Diseases such as tuberculosis and bronchiectasis are common causes of chronic cough in this country. They are usually not confused with COPD. Physical findings of fibrocavitary disease support a diagnosis of tuberculosis. Sputum is purulent and greater in amount in patients with bronchiectasis. Coarse crepitations and finger clubbing are generally present.

Any chronic lung disease can occasionally pose a problem in differential diagnosis. Whenever, there is confusion, investigations will help.

Presence of complications

1. Chronic cor pulmonale: Almost all cases of COPD will progress to chronic cor pulmonale in due course of time. It is detected from the presence of signs suggestive of pulmonary hypertension and right ventricular enlargement and/or failure, such as a loud second heart sound, parasternal heave and raised jugular venous pressure (JVP).

2. Respiratory failure: Chronic respiratory failure results from disease progression. It is suspected from the presence of tachypnea, cyanosis, flapping tremors, and altered sensorium.

3. Chest infections, such as pneumonias.

4. Pneumothorax.