Routsi C, Vincent J L, Bakker J, De Backer D, Lejeune P, d'Hollander A, Le Clerc J L, Kahn R J
Department of Intensive Care, Erasme University Hospital, Free University of Brussels, Belgium.
Anesth Analg. 1993 Dec;77(6):1104-10. doi: 10.1213/00000539-199312000-00004.
The relative contributions of oxygen delivery (DO2) and oxygen extraction (O2ER) to the increase in cellular oxygen uptake (VO2) after cardiopulmonary bypass were studied prospectively in 36 patients after coronary artery bypass grafting (n = 18), valve replacement (n = 17), and removal of a left atrial tumor (n = 1). VO2 was calculated from the Fick equation and DO2 from thermodilution cardiac output and arterial oxygen content. During the first 24 h after cardiac surgery, there was a strong relation between VO2 and DO2 (VO2 = 28 + 0.27 x DO2, r = 0.79, P < 0.0001) but not between VO2 and oxygen extraction. Mixed venous oxygen saturation (SVO2) was usually reduced when cardiac index was below 2.0 L.min-1.m-2. Patients with a prolonged intensive care unit course (> 24 h) had lower cardiac index and lower SVO2 than the other patients. Therefore, the progressive increase in VO2 after cardiac surgery is accomplished primarily by an increase in cardiac output and DO2. It is usually when cardiac function is compromised that O2ER increases and SVO2 decreases.
前瞻性研究了36例冠状动脉搭桥术（n = 18）、瓣膜置换术（n = 17）和左心房肿瘤切除术（n = 1）患者体外循环后氧输送（DO2）和氧摄取（O2ER）对细胞氧摄取量（VO2）增加的相对贡献。VO2根据Fick方程计算，DO2根据热稀释心输出量和动脉血氧含量计算。心脏手术后的最初24小时内，VO2与DO2之间存在密切关系（VO2 = 28 + 0.27×DO2，r = 0.79，P < 0.0001），但VO2与氧摄取之间无此关系。当心脏指数低于2.0 L·min-1·m-2时，混合静脉血氧饱和度（SVO2）通常会降低。重症监护病房病程延长（> 24小时）的患者比其他患者的心脏指数和SVO2更低。因此，心脏手术后VO2的逐渐增加主要是通过心输出量和DO2的增加来实现的。通常在心脏功能受损时，O2ER增加而SVO2降低。
