Upper airway collapsibility, dilator muscle activation and resistance in sleep apnoea

Abstract

The calibre of the upper airway is thought to be dependant upon its passive anatomy/collapsibility and the activation of pharyngeal dilator muscles. During awake periods, the more collapsible upper airway in obstructive sleep apnoea (OSA) increases the dilator muscle activity through a negative-pressure reflex. A direct correlation between the critical closing pressure (P(crit)), as a measure of anatomy/collapsability and electromyogram (EMG) activity of genioglossus EMG (GG-EMG) and tensor palatini EMG (TP-EMG), was hypothesised. The relationship between these indices and pharyngeal resistance (R(phar)) was also examined. The study involved eight males with a mean age of 48 (interquartile r..