经肺动脉插管可以测定肺毛楔入压(PCWP)和心排血量(CO),也可抽取混合静脉血测氧饱和度(SvO_2)。最近由于纤维光导肺动脉导管被引进临床使用,所以已能够连续监测混合静脉血氧饱和度。1959年,Boyd等就报道SvO_2是估计病人心血管状态的一项很可靠的指数,而且比CO或心脏指数(CI)容易测定。用SvO_2计算A-V血氧含量差能准确反映病人当时对CO的需求是否充裕。将它随机与CO测定值 Pulmonary artery catheterization can be measured pulmonary capillary wedge pressure (PCWP) and cardiac output (CO), can also be extracted mixed venous blood oxygen saturation (SvO_2). Recently, fibreoptic pulmonary artery catheters have been introduced for clinical use and have been able to continuously monitor mixed venous oxygen saturation. In 1959, Boyd et al. Reported that SvO 2 was a reliable measure of cardiovascular status in patients and was easier to measure than CO or cardiac index (CI). Using SvO_2 to calculate the difference of A-V blood oxygen content can accurately reflect the patient’s need for CO at the time. It will be random and CO measured value