[Proposal for a systematic analysis of polygraphy or polysomnography for identifying and scoring abnormal events occurring during non-invasive ventilation]. / Proposition pour une analyse systématique de la polygraphie et de la polysomnographie afin d'identifier les évènements anormaux survenant pendant la ventilation non invasive.

Non-invasive ventilation (NIV) is recognised as an effective treatment for chronic hypercapnic respiratory failure. Monitoring NIV during sleep may be preferable to daytime assessment. This paper reports the findings of an international consensus group, which systematically analysed nocturnal polygraphic or polysomnographic tracings recorded with either volume-cycled or pressure-cycled ventilators. A systematic description of nocturnal respiratory events, which occur during NIV, is proposed: leaks, obstruction at different levels of the upper airway (glottis and/or pharynx), with or without decrease of respiratory drive and asynchrony.

Proposal for a systematic analysis of polygraphy or polysomnography for identifying and scoring abnormal events occurring during non-invasive ventilation.

Non-invasive ventilation (NIV) is recognised as an effective treatment for chronic hypercapnic respiratory failure. Monitoring NIV during sleep may be preferable to daytime assessment. This paper reports the findings of an international consensus group which systematically analysed nocturnal polygraphic or polysomnographic tracings recorded with either volume-cycled or pressure-cycled ventilators. A systematic description of nocturnal respiratory events which occur during NIV is proposed: leaks, obstruction at different levels of the upper airway (glottis and/or pharynx), with or without decrease of respiratory drive and asynchrony.

Snoring detection during auto-nasal continuous positive airway pressure.

A bench study using an artificial lung model was performed to evaluate the snoring detection sensitivity of six (commercially available) auto-nasal continuous positive airway pressure (NCPAP) devices. Snoring was simulated by a loudspeaker connected to the lung model and abruptly activated during 1 s of each inspiratory period to induce pressure oscillation. The oscillation frequencies chosen were 30, 60, 90, and 120 Hz. For each frequency, the amplitude of the pressure oscillation produced by the loudspeaker was adjusted to find the threshold at which the auto-nCPAP devices detected snoring. Differences in pressure-amplitude thresholds of up to three-fold were found across auto-nCPAP devices. A randomized clinical study to compare the effects of the least sensitive (Virtuoso LX; Respironics, Nantes, France) and one of the most sensitive, (Goodknight 418A; Malinckrodt, Nancy, France) devices, in two groups of six patients with obstructive sleep apnoea syndrome was then conducted. Goodknight 418A was more sensitive than Virtuoso LX for detecting snoring (mean +/- SD 92 +/- 11% versus 50 +/- 39% respectively, p = 0.03). To conclude, striking differences exist between auto-nasal continuous positive airway pressure devices in sensitivity for detecting snoring.