Bredenberg C E, Paskanik A M
Ann Surg. 1983 Aug;198(2):218-22. doi: 10.1097/00000658-198308000-00018.
The relation of portal hemodynamics to cardiac output (CO) during mechanical ventilation with 15 cm H2O PEEP was studied in 12 dogs under pentobarbital anesthesia. Cardiac output was measured by thermal dilution. Portal vein flow (PF) and superior mesenteric artery flow (SMAF) were measured by electromagnetic flow probes. Intraesophageal, intraabdominal, portal vein (PVP) and intrathoracic caval (CVP) pressures, as well as the intraluminal venous pressure gradient across the liver (PVP-CVP) were measured. Intravascular volume was expanded with dextran prior to the addition of PEEP. In nine animals, dextran plus PEEP maintained CO and visceral flows within 3% of control. In three animals, CO and visceral flows fell to the same proportion. There was no increase in hepatic resistance. PF showed a linear correlation with SMAF, and SMAF had a linear correlation with CO. In these experiments, the effect of PEEP on portal hemodynamics system is primarily the consequence of reduced CO.
在戊巴比妥麻醉下，对12只狗进行研究，观察在15 cm H₂O呼气末正压（PEEP）机械通气期间门静脉血流动力学与心输出量（CO）的关系。采用热稀释法测量心输出量。通过电磁血流探头测量门静脉血流（PF）和肠系膜上动脉血流（SMAF）。测量食管内、腹腔内、门静脉压力（PVP）和胸段腔静脉压力（CVP），以及肝脏内的管腔内静脉压力梯度（PVP - CVP）。在添加PEEP之前，用右旋糖酐扩充血管内容量。在9只动物中，右旋糖酐加PEEP使CO和内脏血流维持在对照值的3%以内。在3只动物中，CO和内脏血流下降到相同比例。肝阻力没有增加。PF与SMAF呈线性相关，SMAF与CO呈线性相关。在这些实验中，PEEP对门静脉血流动力学系统的影响主要是CO降低的结果。
