Pulse Oximetry Reliability for Detection of Hypoxemia under Motion in Extremely Premature Infants

BACKGROUND: Episodes of intermittent hypoxemia (IH) in extremely premature infants are detected by pulse oximetry (SpO(2)) but motion artifact can cause falsely low readings. OBJECTIVES: To evaluate the reliability of SpO(2) during IH episodes associated with motion in premature infants of ≤ 28w GA monitored with 2 pulse oximeters. METHODS: IH episodes (defined as SpO(2)<90%, >10s and SpO(2)<80%, >10s) were classified by an analytic tool based on distortion caused by motion in the pulse plethysmograph (Pleth) as: A (true-hypoxemia), both SpO(2) decreased (only one Pleth showed motion), B (false-hypoxemia), one SpO(2) decreased (Pleth showed motion) and the other didn’t (Pleth didn’t show motion); C (suspected-hypoxemia), both SpO(2) decreased (both Pleth showed motion); D (true-hypoxemia-motion-free), both SpO(2) decreased (neither Pleth showed motion). RESULTS: In 24–72h data from 20 infants of 25.4±1.5w GA, 14.1±5.7 episodes with SpO(2)<90% and 7.9±5.5 episodes with SpO(2)<80% per infant were identified. 29±15% of episodes with SpO(2)<90% were type A, 1±2% B, 43±21% C and 27±23% D while 26±22% of episodes with SpO(2)<80% were type A, .3±1.2% B, 45±29% C and 19±25% D [p<.001 type B vs rest (GLM-repeated measures)]. CONCLUSION: In extremely premature infants SpO(2) with motion artifact is more likely to indicate true- than false-hypoxemia.