Validation of nasal pressure for the identification of apneas/hypopneas during sleep.

The reference standard for identifying apneas and hypopneas is a pneumotachograph, but using this can disrupt sleep. Nasal airflow estimation by measuring nasal pressure via nasal prongs is better tolerated by patients. However, nasal pressure has not been validated, using an event-by-event analysis, for detecting apneas/hypopneas during sleep.