Inspiratory flow limitation in obstructive sleep apnoea patients.

Patients suffering from the obstructive sleep apnoea syndrome (OSAS) experience nocturnal episodes of upper airway obstruction resulting in recurrent oxygen desaturations and arousals. Methods to quantify the nocturnal obstructive events are of interest for characterizing this prevalent sleep disorder. In a study published in this issue of Clinical Science, Bloch and co-workers propose the computation of a new index for objectively quantifying the degree of flow limitation in patients with OSAS. The results obtained in a bench test and in a pilot study in patients suggest that the flow limitation index proposed may help to better characterize the disturbed breathing events undergone by patients with OSAS.