An experimental study on circulatory physiology of nonpulsatile bloodcirculation under awake condition

尽管非搏动循环在临床环境中被广泛应用，并且通常被认为是可行的，但哺乳动物搏动衰竭的病理生理学尚未被清楚地理解。本研究旨在探讨非搏动循环的循环生理学，以尽量减少不利的额外因素的影响。首先，我们使用离心型连续血流血泵研究了成年山羊在清醒状态下对无搏动全身循环或肺循环的生理反应。在血液动力学、代谢、血管活性激素和外周循环条件下，体循环降搏未显示出任何显著的不良影响。肺循环衰竭也不影响肺循环状况和肺功能。从这些结果，我们得出结论，清醒的哺乳动物立即适应无搏动的体循环或肺循环。在第一个系列研究中，更令人费解的是这种哺乳动物是如何适应非搏动循环的。因此，在第二项研究中，我们研究了成年山羊左心全搭桥模型急性动物实验中神经和体液控制系统对非搏动循环的急性期反应。降压后，肾交感神经活动（RSNA）的脉冲同步爆发立即消失，平均RSNA升高120%。在各种血管活性激素水平评估中，只有去甲肾上腺素在去搏动后显著升高，且平均主动脉压脉动与非脉动差值与去甲肾上腺素水平之间存在显著的负相关关系。由此可见，以去甲肾上腺素水平为代表的交感神经系统活动在非搏动循环中高于搏动循环，压力感受器反射在体循环降搏后的急性期起作用。少

Although nonpulsatile circulation is widely used in the clinical setting and is generally conceived to be feasible, pathophysiology of depulsated mammals has not yet been clearly understood. The present study was undertaken to inquire circulatory physiology of nonpulsatile circulation in an effort to minimize the influence of untoward extra factors. First, we investigated physiologic responses of adult goats to nonpulsatile systemic or pulmonary circulation under awake condition in a total left or right heart bypass model using centrifugal-type continuous flow blood pump. Depulsation of systemic circulation did not show any significant adverse effects in hemodynamic, metabolic, vasoactive hormonal, and peripheral circulatory conditions. Depulsation of pulmonary circulation also did not affect pulmonary circulatory conditions as well as pulmonary functions. From these results, we concluded that an awake mammal acclimates immediately to nonpulsatile systemic or pulmonary circulation. Rem … More ained obscure in this first series study was how does the mammal acclimate to nonpulsatile circulation. In the second study, therefore, we looked into acute phase responses of the nervous and humoral control systems to nonpulsatile circulation in acute animal experiments of total left heart bypass model using adult goats. After the depulsation, pulse-synchronized bursts of the renal sympathetic nerve activity (RSNA) disappeared immediately and the mean RSNA increased up to 120%. Among various vasoactive hormone levels evaluated, only norepinephrine showed significant increase after the depulsation, and a significant reciprocal correlation was found between the magnitude of pulsatile-nonpulsatile differences in mean aortic pressure and norepinephrine levels. From these results, we concluded that activity of the sympathetic system represented by norepinephrine level is higher in nonpulsatile than pulsatile circulation, and the baroreceptor reflex functions in acute phase after the depulsation of systemic circulation. Less