Feng An-Chieh, Chen Teng-Wei, Fan Hsiu-Lung, Yu Jyh-Cherng, Hsieh Chung-Bao
From the Division of General Surgery, Department of Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, Republic of China.
Medicine (Baltimore). 2015 Oct;94(43):e1815. doi: 10.1097/MD.0000000000001815.
The correlation between portal vein pressure (PVP) and flow (PVF) has not been established, and there is still lack of consensus about the optimal hemodynamics during liver transplantation (LT). We aimed to establish the correlation between systemic and hepatic hemodynamics during LT by applying the hepatokinetic power hypothesis, based on the law of energy conservation and hydrodynamics.A total of 103 adult liver transplant recipients were enrolled in this study from September 2012 to December 2014. Systemic and hepatic hemodynamics were assessed intraoperatively to calculate the hepatokinetic power status. Severe surgical complications (Clavien-Dindo grade ≥III) were recorded as the main outcome measure, and potential covariates were evaluated including recipient, donor, donor-recipient match, surgery-related factors, conventional hemodynamics, and the intraoperative hepatokinetic power profile.In multivariate analysis, hepatokinetic power gradient >4260 mL mmHg min100 g graft weight (P = 0.001), 2.2 < ratio of hepatokinetic power from the portal vein to the hepatic artery ≤8.7 (P = 0.012), and hepatic resistance of partial grafts ≤0.006 or >0.015 min mmHg mL (P = 0.012) were associated with a higher risk. None of the conventional hemodynamic parameters, such as PVP, PVF, and hepatic venous pressure gradient, entered into this regression model (c-statistic = 0.916) when competing with hepatokinetic power indexes.The hepatokinetic power hypothesis clarifies the correlation of systemic and hepatic hemodynamics in a simple, rational manner. The hepatic resistance, derived from the hepatokinetic power equation, can be quantified and has an effect on the incidence of severe surgical complications. This finding offers a new objective clinical approach to evaluate graft quality during transplantation.
门静脉压力（PVP）与血流量（PVF）之间的相关性尚未明确，对于肝移植（LT）期间的最佳血流动力学仍缺乏共识。我们旨在通过应用基于能量守恒定律和流体动力学的肝动力功率假说，来确定LT期间全身和肝脏血流动力学之间的相关性。
2012年9月至2014年12月，共有103例成年肝移植受者纳入本研究。术中评估全身和肝脏血流动力学，以计算肝动力功率状态。记录严重手术并发症（Clavien-Dindo分级≥III级）作为主要结局指标，并评估潜在的协变量，包括受者、供者、供受者匹配情况、手术相关因素、传统血流动力学以及术中肝动力功率曲线。
多因素分析显示，肝动力功率梯度>4260 mL mmHg min/100 g移植物重量（P = 0.001）、门静脉与肝动脉的肝动力功率比值2.2 <比值≤8.7（P = 0.012）以及部分移植物的肝阻力≤0.006或>0.015 min mmHg/mL（P = 0.012）与较高风险相关。当与肝动力功率指标竞争时，PVP、PVF和肝静脉压力梯度等传统血流动力学参数均未进入该回归模型（c统计量 = 0.916）。
肝动力功率假说以简单、合理的方式阐明了全身和肝脏血流动力学的相关性。源自肝动力功率方程的肝阻力可以量化，并对严重手术并发症的发生率有影响。这一发现为评估移植期间移植物质量提供了一种新的客观临床方法。
