UPPER AIRWAY-RESISTANCE SYNDROME

Obstruction of the upper airway may cause arousals resulting in daytim e sleepiness and cardiovascular disturbances. The upper airway resista nce syndrome may easily be overlooked because conventional measurement s of oronasal airflow and thoracic and abdominal efforts are not sensi tive enough. By measuring esophageal pressure even small disturbances can be detected, but the esophageal gauge may disturb sleep. We conclu de that other, less invasive methods like measurements of impedance by forced oscillation technique, or flattening of the inspiratory flow c ontour could be valid alternatives in the diagnosis of the upper airwa y resistance syndrome. Other methods, such as measurements of the puls e transit time, phase angle, or systolic blood pressure profile are pr omising, but need further evaluation.