Upper airway collapsibility: measurement techniques and therapeutic implications.

Several techniques are currently available that aim to characterize upper airway function/mechanics during wakefulness or sleep. Based on the concept of a Starling resistor, we propose a standardized protocol to measure the critical pressure (Pcrit) (an indicator of upper airway collapsibility) during sleep. The effect of therapeutic interventions such as weight loss, positional changes or uvulopalatopharyngoplasty on Pcrit is illustrated by data from the literature. We propose that measurement of Pcrit become implemented in the diagnostic work-up of selected patients with sleep-related breathing disorder to help making a correct therapeutic decision.