Shafqat K, Langford R M, Pal S K, Kyriacou P A
School of Engineering and Mathematical Sciences (SEMS), City University London, London, UK.
Annu Int Conf IEEE Eng Med Biol Soc. 2012;2012:2905-8. doi: 10.1109/EMBC.2012.6346571.
In this study, finger photoplethysmograph data obtained from twelve patients undergoing cardiothoracic surgery were analyzed in order to estimate the venous saturation utilizing the modulations created by the positive pressure ventilation in the AC Photoplethysmograph (PPG) signals. The PPG signals were analyzed in the time-domain using a conventional pulse oximetry algorithm to produce estimations of arterial oxygen saturation. The instantaneous arterial and venous saturations were estimated by utilizing time-frequency analysis technique of Smoothed-pseudo Wigner-Ville Distribution (SPWVD). The results showed that there was no significant difference in the traditionally-derived (time-domain) arterial saturation and the instantaneous arterial saturation. However, the instantaneous venous saturation was found to be significantly lower than the time-domain estimated and instantaneous arterial saturation (P=<0.001).
在本研究中，分析了从12名接受心胸外科手术的患者获取的手指光电容积脉搏波描记图数据，以便利用交流光电容积脉搏波描记图（PPG）信号中由正压通气产生的调制来估计静脉饱和度。使用传统脉搏血氧饱和度测定算法在时域中分析PPG信号，以得出动脉血氧饱和度的估计值。利用平滑伪维格纳-威利分布（SPWVD）的时频分析技术估计瞬时动脉和静脉饱和度。结果表明，传统方法得出的（时域）动脉饱和度与瞬时动脉饱和度之间无显著差异。然而，发现瞬时静脉饱和度显著低于时域估计值和瞬时动脉饱和度（P<=0.001）。
