Pastor C M
Division d'Investigations Anesthésiologiques, University of Geneva, Switzerland.
Crit Care Med. 2000 Mar;28(3):765-73. doi: 10.1097/00003246-200003000-00027.
To compare the hepatosplanchnic oxygen consumption (VO2) with the hepatic and splanchnic VO2 and to calculate the critical oxygen delivery (DO2crit) below which VO2 decreases in the hepatic, splanchnic, and hepatosplanchnic regions in a model of hypoxemic hypoxia.
Prospective animal study.
University research laboratory.
Anesthetized and ventilated pigs (n = 7).
The right carotid artery was cannulated to measure mean arterial pressure. A pulmonary artery catheter was inserted to measure mean pulmonary arterial pressure and cardiac output. After a midline abdominal incision, two flow probes were positioned around the portal vein and the hepatic artery to measure portal vein blood flow and hepatic artery blood flow. Oxygen and lactate contents in the carotid artery, the portal vein, and the hepatic vein were measured in blood samples obtained from the appropriate catheters.
After a 2-hr stabilization period, hemodynamic and biological variables were recorded during acute hypoxemic hypoxia (FIO2 = 0.5, 0.4, 0.3, 0.21, 0.15, 0.10, and 0.07). VO2, DO2, and DO2crit were determined in the hepatic, splanchnic, and hepatosplanchnic regions. The hepatosplanchnic VO2 was 48 +/- 5 mL/min at high FIO2 (40% for the liver and 60% for the splanchnic organs) and decreased below FIO2 of 0.15. Lactate uptake in the whole hepatosplanchnic region remained steady at FIO2 values of 0.5 to 0.15 and then switched to a lactate release at low FIO2. However, the splanchnic region released lactate, whereas lactate was taken up by the liver. DO2crit in the hepatic, splanchnic, and hepatosplanchnic regions was 24 +/- 3, 38 +/- 2, and 49 +/- 4 mL/min, but the systemic DO2crit, below which regional VO2 became oxygen supply dependent, did not differ in the liver, splanchnic, and hepatosplanchnic regions.
The variables of oxygenation and lactate flux measured in the hepatosplanchnic region summarize the metabolic changes of various organs that may vary in different ways during hypoxemic hypoxia.
比较肝脾氧耗（VO2）与肝脏和脾脏的VO2，并计算在低氧性缺氧模型中肝脏、脾脏和肝脾区域VO2下降时的临界氧输送（DO2crit）。
前瞻性动物研究。
大学研究实验室。
麻醉并通气的猪（n = 7）。
插入右颈动脉导管测量平均动脉压。插入肺动脉导管测量平均肺动脉压和心输出量。经腹部中线切口后，在门静脉和肝动脉周围放置两个流量探头，测量门静脉血流量和肝动脉血流量。从相应导管采集的血样中测量颈动脉、门静脉和肝静脉中的氧和乳酸含量。
经过2小时的稳定期后，在急性低氧性缺氧（FIO2 = 0.5、0.4、0.3、0.21、0.15、0.10和0.07）期间记录血流动力学和生物学变量。在肝脏、脾脏和肝脾区域测定VO2、DO2和DO2crit。在高FIO2时（肝脏占40%，脾脏器官占60%）肝脾VO2为48±5 mL/分钟，在FIO2低于0.15时下降。在FIO2值为0.5至0.15时，整个肝脾区域的乳酸摄取保持稳定，然后在低FIO2时转变为乳酸释放。然而，脾脏区域释放乳酸，而肝脏摄取乳酸。肝脏、脾脏和肝脾区域的DO2crit分别为24±3、38±2和49±4 mL/分钟，但区域VO2变为氧供依赖性时的全身DO2crit在肝脏、脾脏和肝脾区域并无差异。
在肝脾区域测量的氧合和乳酸通量变量总结了在低氧性缺氧期间可能以不同方式变化的各个器官的代谢变化。
