Variability in time delay between two models of pulse oximeters for deriving the photoplethysmographic signals.

摘要: Pulse oximetry is commonly used as an arterial blood oxygen saturation (SaO2) measure. However, its other serial output, the photoplethysmography (PPG) signal, not well studied. Raw PPG signals can be to estimate cardiovascular measures like pulse transit time (PTT) and possibly heart rate (HR). These timing-related measurements are heavily dependent on minimal variability in phase delay of signals. Masimo SET Rad-9 Novametrix Oxypleth oximeters were investigated for their characteristics nine healthy adults. To facilitate comparison, acquired from fingers same hand a random fashion. Results showed that mean PTT variations oximeter (37.89 ms) much greater than (5.66 ms). Documented evidence suggests 1 ms variation equivalent mmHg change pressure. Moreover, trend derived mistaken obstructive sleep apnoeas based known criteria. HR comparison was evaluated against estimates attained electrocardiogram (ECG). differed ECG by 0.71+/-0.58% (p 0.05). Modern attractive improved SaO2 measurement. using raw obtained directly these warrants further investigations.