Oximeter's acquisition parameter influences the profile of respiratory disturbances

STUDY OBJECTIVES: Pulse oximetry (Sp02) is a key parameter monitored during polysomnographic studies, and different acquisition settings can be employed to obtain this data. The purpose of this study was to determine if the use of different settings would significantly influence scoring of respiratory disturbance events (RDE). DESIGN: Prospective study SETTING: Sleep Disorders Center - community PATIENTS: 30 patients had three identical oximeters simultaneously attached to the digits during polysomnography, each placed in a different recording setting: 3, 6 and 12 seconds. INTERVENTIONS: None. MEASUREMENTS: RDEs were identified by changes in snoring and flow then sub-categorized as RDE0, RDE1-2 and/or RDE3 if less than 1%, greater than 1 but less than 3%, and 3% or greater oxyhemoglobin desaturation occurred. Each event was given three labels according to the level of desaturation seen on each oximetry tracing. RESULTS: Significant differences in the mean frequency of RDE types at each recording setting were noted (p < .001). A survey of sleep practitioners revealed changes in clinical behavior when presented examples of such differences. CONCLUSION: These data confirm the impact of different oximetric recording settings on the profile of RDEs and the importance of reporting such acquisition settings in studies of sleep disordered breathing.