PROBLEM TO BE SOLVED: To calculate a mixed vein blood oxygen saturation degree in a low invasive manner with accuracy.SOLUTION: A blood index calculation part 12 calculates at least a part of a blood index related to oxygen transport based on transmitted light or reflection light when lights of plural wavelengths are radiated to an optional living body portion of a subject. An oxygen consumption amount calculation part 13 calculates an oxygen consumption amount based on inspiration gas density, expiration gas density and a ventilation volume. A cardiac output calculation part 14 calculates a cardiac output based on a living body signal which is acquired from the subject in a non-invasive method. An SvO2 estimation part 15 substitutes the blood index, oxygen consumption amount and cardiac output to a calculation formula which is derived from a blood circulation law and an oxygen coupling amount for a unit hemoglobin, for estimating a mixed vein blood oxygen saturation degree of the subject.SELECTED DRAWING: Figure 1COPYRIGHT: (C)2017,JPO&INPIT【課題】非侵襲で精度良く混合静脈血酸素飽和度を算出すること。【解決手段】血液指標算出部12は、複数波長の光を被験者の任意の生体部位に照射した際の透過光又は反射光に基づき、酸素運搬にかかる血液指標の少なくとも一部を算出する。酸素消費量算出部13は、被験者の吸気ガス濃度、呼気ガス濃度、及び換気量に基づいて酸素消費量を算出する。心拍出量算出部14は、被験者から非侵襲な手法で取得した生体信号に基づいて、心拍出量を算出する。SvO2推定部15は、血液循環則と単位ヘモグロビンあたりの酸素結合量とから導かれる算出式に対し、血液指標、酸素消費量、及び心拍出量を代入して、被験者の混合静脈血酸素飽和度を推定する。【選択図】図1
