Breathing-related changes of respiratory resistance in vocal cord dysfunction.

Vocal cord dysfunction induced by exercise in children with uncontrolled asthma was identified by laryngoscopy. The paradoxical adduction of the vocal cords was also indicated by the breathing-related changes of the forced oscillation respiratory resistance showing prominent increase during inspiration and a large positive difference between inspiration and expiration. The breathing-related changes of respiratory resistance offer thus a useful first-line technique to diagnose vocal cord dysfunction.

A systematic review of lung function testing in asthmatic young children.

Asthma diagnosis is difficult in young children being mainly based on clinical signs and parents' history, which is sometimes difficult to obtain. Lung function testing may improve asthma diagnosis by objectively assessing its main features, airway obstruction, spontaneously reversible or after use of a bronchodilator drug, ventilation inhomogeneity during an acute bronchoconstriction and airway hyperresponsiveness. In young children that cannot cope with classical tests, it is important to use and develop simple, short lasting methods, made in spontaneous ventilation without active cooperation.

Specific airway resistance in healthy young Vietnamese and Caucasian adults.

In healthy Vietnamese children the respiratory resistance has been suggested to be similar at 110 cm height but larger at 130 cm when compared with data in Caucasians from the literature, suggesting smaller airways in older Vietnamese children (Vu et al., 2008). The hypothesis tested here is whether the difference in airway resistance remains consistent throughout growth, and if it is larger in adult Vietnamese than in Caucasians.

Neonatal hyperoxia up regulates cough reflex in young rabbits.

A link between cough in childhood and neonatal exposure to hyperoxia following preterm birth has been suggested. The hypothesis is tested that neonatal exposure to hyperoxia is associated with long term up regulation of cough. Airway hyperresponsiveness is also investigated because it is a frequent finding in children born preterm and may be linked to cough.

Airway obstruction, upper airway artifact and response to bronchodilator in asthmatic and healthy children.

Background: The forced oscillation technique (FOT) may be affected by the upper airway artifact in children with airway obstruction. The aim was to test the impact of the artifact on FOT ability to diagnose asthma in children as recommended by current guidelines.

Methods: The FOT was performed in 58 asthmatics and 27 controls before and after salbutamol.