Alvarez D, de las Heras M, Abecasis R, Terg R, Gerona S, Albornoz L, Galdame O, Torres J, Mastai R
Seccion Ecografia, Universidad de Buenos Aires, Argentina.
Hepatology. 1997 Mar;25(3):548-50. doi: 10.1002/hep.510250309.
A nocturnal increase in portal pressure and blood flow was demonstrated in patients with cirrhosis, suggesting that these hemodynamic changes may contribute to the triggering of the hemorrhagic episodes observed during the night in these patients. It is known that propranolol reduces portal flow, thus reducing the risk of variceal bleeding. In a double-blind, placebo-controlled study, we evaluated the effect of long-term propranolol administration on the daily fluctuation of systemic and splanchnic hemodynamic parameters in 14 patients with cirrhosis. Cardiac output and portal blood flow were measured by the Doppler technique. A daily fluctuation of both cardiac output and portal blood flow was observed, peaking at midnight. beta-Adrenergic blockade was manifested by a significant reduction in heart rate (-21% +/- 4%, P < .01) and cardiac output (-12% +/- 2%, P < .05). A significant decrease in portal blood flow (-20% +/- 4%, P < .01) was also observed in these patients. Propranolol administration blunted the time-related changes in cardiac output and portal blood flow. In contrast, patients receiving placebo had a nocturnal peak of both parameters similar to that observed under basal conditions. Our study shows that chronic propranolol administration abolishes the nocturnal peak of portal blood flow in patients with cirrhosis and indicates a preventive effect of propranolol in these patients.
肝硬化患者夜间门静脉压力和血流量增加,提示这些血流动力学变化可能促使这些患者夜间出现出血发作。已知普萘洛尔可减少门静脉血流量,从而降低静脉曲张出血风险。在一项双盲、安慰剂对照研究中,我们评估了长期给予普萘洛尔对14例肝硬化患者全身和内脏血流动力学参数每日波动的影响。采用多普勒技术测量心输出量和门静脉血流量。观察到心输出量和门静脉血流量均有每日波动,在午夜达到峰值。β-肾上腺素能阻滞表现为心率显著降低(-21%±4%,P<.01)和心输出量降低(-12%±2%,P<.05)。这些患者的门静脉血流量也显著减少(-20%±4%,P<.01)。给予普萘洛尔可减弱心输出量和门静脉血流量与时间相关的变化。相比之下,接受安慰剂的患者这两个参数的夜间峰值与基础状态下观察到的相似。我们的研究表明,长期给予普萘洛尔可消除肝硬化患者门静脉血流量的夜间峰值,并提示普萘洛尔对这些患者有预防作用。