Stadlbauer Vanessa, Wright Gavin A K, Banaji Murad, Mukhopadhya Ashis, Mookerjee Rajeshwar P, Moore Kevin, Jalan Rajiv
Liver Failure Group, Institute of Hepatology, Division of Medicine, University College London, London, England.
Gastroenterology. 2008 Jan;134(1):111-9. doi: 10.1053/j.gastro.2007.10.055.
BACKGROUND & AIMS: It has been proposed that activation of the sympathetic nervous system causes a rightward shift in the renal autoregulatory curve such that renal blood flow is critically dependent on renal perfusion pressure and that this contributes to the development of the hepatorenal syndrome. The aims of the study were to determine the relationship of renal blood flow and renal perfusion pressure in patients with liver cirrhosis and the effect on renal hemodynamics following insertion of a transjugular intrahepatic portosystemic shunt (TIPS).
Fifty-six patients were recruited into groups (1) with no ascites, (2) with diuretic-responsive ascites, (3) with intractable ascites, (4) with type II hepatorenal syndrome, and (5) requiring a TIPSs for refractory ascites. We measured cardiac hemodynamics, renal blood flow, renal perfusion pressure, and portal pressure and norepinephrine levels and mathematically modeled the renal autoregulatory curve.
Renal blood flow correlated with renal perfusion pressure (r(2) = 0.78; P < .001) and inversely with the hepatic venous pressure gradient (r(2) = 0.61; P < .0001) and plasma norepinephrine levels (r(2) = 0.78; P < .0001). Norepinephrine levels increased with increasing disease severity, and this was associated with a rightward and downward shift of the renal blood flow/renal perfusion pressure autoregulatory curve. TIPS insertion reduced portal pressure and plasma norepinephrine levels (P < .001), and the renal blood flow/renal perfusion pressure curve was shifted upward.
The relationship between renal blood flow and renal perfusion pressure involves a critical interplay between the sympathetic nervous system and the kidney. TIPS insertion decreases sympathetic activation and improves renal function through positive effects on renal blood flow autoregulation.
有人提出，交感神经系统的激活会导致肾自动调节曲线向右移位，从而使肾血流量严重依赖于肾灌注压，且这会促使肝肾综合征的发生。本研究的目的是确定肝硬化患者肾血流量与肾灌注压之间的关系，以及经颈静脉肝内门体分流术（TIPS）置入后对肾血流动力学的影响。
56例患者被分为以下几组：（1）无腹水组；（2）利尿剂反应性腹水组；（3）顽固性腹水组；（4）II型肝肾综合征组；（5）因难治性腹水需要进行TIPS治疗组。我们测量了心脏血流动力学、肾血流量、肾灌注压、门静脉压力和去甲肾上腺素水平，并对肾自动调节曲线进行了数学建模。
肾血流量与肾灌注压相关（r² = 0.78；P < 0.001），与肝静脉压力梯度呈负相关（r² = 0.61；P < 0.0001），与血浆去甲肾上腺素水平呈负相关（r² = 0.78；P < 0.0001）。去甲肾上腺素水平随疾病严重程度的增加而升高，这与肾血流量/肾灌注压自动调节曲线向右下方移位有关。TIPS置入降低了门静脉压力和血浆去甲肾上腺素水平（P < 0.001），肾血流量/肾灌注压曲线向上移位。
肾血流量与肾灌注压之间的关系涉及交感神经系统与肾脏之间的关键相互作用。TIPS置入可减少交感神经激活，并通过对肾血流自动调节的积极作用改善肾功能。
