Quantifying Asynchronous Breathing

Abstract

This chapter describes a simple computer algorithm of quantifying inductance plethysmography thoracic and abdominal signals and integrating it with sleep stages, disordered breathing events, and body position that can be used in clinical and research polysomnographic studies. The method of quantifying asynchrony is a modification of the linear transfer function method, a method that has been shown to be extremely accurate. This algorithm can be performed rapidly with a laptop computer and can be easily integrated into results from polysomography. The studies indicate that this algorithm may be useful for the diagnosis of obstructive sleep-disordered breathing. They also indicate that it may also be of use to speed technician scoring polysomnography studies by indicating regions of the study that contain events of interest such as arousals and awake periods. This algorithm is particularly useful because the measurements of chest and abdomen movements are nonintrusive. Thus, it can potentially be used in an outpatient environment and with children.