Flow limitation as a noninvasive assessment of residual upper-airway resistance during continuous positive airway pressure therapy of obstructive sleep apnea.

摘要: Many patients with obstructive sleep apnea syndrome (OSAS), despite therapy nasal continuous positive airway pressure (CPAP), have persisting daytime somnolence that may be due to a persistently elevated upper-airway resistance associated electroencephalographic (EEG) arousals. We tested the hypothesis can inferred from contour of inspiratory flow tracing obtained conventional CPAP circuit. This provide noninvasive method for determining optimal CPAP. Data were collected during titration an model and in eight OSAS. Estimated was calculated esophageal pressure, mask flow. At high CPAP, low found rounded. developed plateau suggesting limitation. also noted at which developed, limitation appeared, showed hysteresis. conclude when respiration is stable, system used infer presence Optimizing alternative eliminating apneas evaluation therapeutic level