Cough : Learning Of Duration, Character, Quality, Timing, And Treatment

Cough is a sudden and often repetitively occuring reflex which helps to clear the large breathing passages from secretions, irritants, foreign particles, and microbes.A respiratory tract infection causes irregular cough.Cough is classified by its duration, character, quality, and timing.

The causes of irregular cough are triggered :

• Air polution
• Smoking
• Choking
• Heart failure
• Asthma
• Post-nasal drip
• Chronic bronchitis
• Lung tumors
• Gastroesophageal reflux disease (GERD)
• Medications (ACE inhibitors)

The cough reflex consists of three phases :

1. An inhalation.
2. A forced exhalation against a closed glottis.
3. A violent release of the air from the lungs following opening of glottis.

The duration of cough can be divided into three :

1. Acute (of sudden onset) is present less than three weeks.It is usually determined by family history and physical exam.

The common causes of acute cough

• Upper respiratory tract infections.They are caused by infection with a germ (virus).
• Lower respiratory tract infections.They are caused by infection with germs (viruses, bacteria or fungi).
• Throat clearing secondary to laryngitis or pharyngitis.
• Post-nasal drip results from rhinitis and sinusitis.It is mucous accumulation in the back of the nose and throat leading to or giving sensation of mucus dripping downward from the back nose.

2. Subacute is present between three and eight weeks.

The common causes of subacute cough

• Post infectious cough
• Acute sinusitis
• Airway hyper-responsiveness is airways  that are slow to settle down after an infection.In this case the germ has gone, but the airways are still swollen and irritable.So it causes to keep coughing.

3. Chronic lasts longer than eight weeks.For patients with chronic cough often represent more of a diagnostic challenge like individuals  with a normal examination, chest radiograph and lung function tests.

The causes of chronic cough

• Post-nasal drip secondary to nasal or sinus disease.
• Asthma.
• Gastroesophageal reflux disease (GERD) may require ambulatory pH monitoring or a prolonged trial of antireflux therapy to diagnose.

A cough can be productive or non productive.It may occur only at night (nocturnal cough), or just at day, and during both night and day.

• Non productive cough ( dry ) does not produce sputum.

The symptoms of non productive cough

- The throat feels itchy and scratchy due to the dryness.

- The throat pains due to excessive coughing.

-  It is difficult to eat.

-  Fever.

The causes of non productive cough 

- Virus infection.

- Dry or cold air.

- Air pollutants such as tobacco smoke, dust, and smog.

• Productive cough produces phlegm or mucus (sputum).The mucus may have drained down the back of the throat from the nose or sinuses or may have come up from the lungs.It is associated with tuberculosis, bronchitis, and bacterial pneumonia.The loose productive cough is a sign of chest congestion or infection due to colds or flu.It clears the lungs and air passages of excess mucus.

Phlegm is a sticky material from mucous membranes in respirarory system.Normal phlegm is usually clear.An infection of phlegm is greenish brown.It is yellowish brown to have a cold.

The causes of productive cough

- Viral illness.

- Infections of the lungs or upper airway passages.

- Stomach acid backing up into the esophagus.

- Nasal discharge  (post-nasal drip) drains down the back of the throat.

- Smoking.

The characteristics of cough originating at various levels of respiratory tract :

• Pharynx 

Its cause is Post-nasal drip and its characteristic  is usually persistent

• Larynx :

Its causes are Laryngitis, tumor, whooping cough, croup.

Their characteristics are harsh, barking, painful, persistent, often associated with strider.

• Trachea 

Its cause is Tracheitis and its characteristic is painful.

• Bronchi

 its causes are

- Acute bronchitis and COPD : their characteristics are dry, productive and worse in morning

- Asthma : its characteristics is dry, productive and worse at night.

- Bronchial carcinoma : its characteristics are persistent and often with haemoptysis.

• Lung parenchyma

The causes of lung parenchyma

- Tuberculosis : its characteristics are productive and often with haemoptysis.

- Pneumonia : its characteristics are dry and productive later.

- Pulmonary edema : its characteristic is often worse at night.

- Interstitial : its characteristics are dry, irritant and distressing.

The Treatment

• Antibiotics may be required to an acute infection like pneumonia.
• An asthma-induced cough may be treated with bronchodilators or antihistamine.
• An Antihistamine is used for Allergic cough.
• Cough medicines may be used for coughs associated with colds and flu.
• The antitussives and Expectorants are two types of drug to treat cough.
• A trial of antibiotics or inhaled corticosteroids may be tried in children  with a chronic cough in an attempt to treat protracted bachterial bronchitis or asthma respectively.
• Physicians prefer not to suppress as a productive cough, since it aids the body in clearing respiratory system of infective agents and irritants.
• Treatment of a cough generally involves the condition of causing it.