Cough

Cough:

—  Cough is a protective reflex

—  Expulsion of respiratory secretions or foreign particles from air passages

—  Occurs due stimulation of mechano or chemo receptors in throat, respiratory passages or stretch receptors in the lungs.

Cough reflex:

—  Pulmonary irritant receptors (cough receptors) in the epithelium of the respiratory tract are sensitive to both mechanical and chemical stimuli.

—  The cough receptor are located mainly on the posterior wall of the trachea, pharynx, and at the main carina

—  When these receptors triggered, impulses travel via the internal laryngeal nerve, to the medulla of the brain.

The cough center in the brain, produces cough which is necessary to remove the foreign material from the respiratory tract before it reaches the lungs.

Types of Cough:

—  Useless(nonproductive) cough which should be suppressed

—  Useful(productive) cough serves to drain the airway

—  It’s suppression is not desirable , may be harmful

Etiology of cough:

—  Upper/ Lower respiratory tract infection

—  Smoking / Chronic Bronchitis

—  Pulmonary tuberculosis

—  Asthmatic cough

—  Postnasal drip due to sinusitis

—  Gastro esophageal reflux

—  ACE inhibitor associated cough