Cough induced by airway vibration as a model of airway hyperreactivity in patients with acute upper respiratory tract infection

Patients with acute upper respiratory tract infection (URTI) have been shown to be hyperreactive to inhaled tussigens such as citric acid and capsaicin, and the authors propose that this may be due to an increased sensitivity of airway receptors that mediate cough. In recent studies we have demonstrated that cough may be induced by vibration of the airway at the level of the throat or chest in patients with URTI but that the same stimuli induce little or no cough in healthy subjects. The difference between the patients with URTI and healthy subjects in their response to airway vibration may be explained on the basis of hyperreactivity of airway sensory receptors. We propose that the model of cough induced by airway vibration may be useful for studies on the pathophysiology and pharmacology of airway hyperreactivity in acute cough. The airway vibration model of cough may have some advantages over inhaled tussigens as the stimulus is easily controlled and the method is safe for use in children.