TEMPERATURE GRADIENTS DURING HYPOTHERMIA
TEMPERATURE GRADIENTS DURING HYPOTHERMIA
复制标题
低温期间的温度梯度
DOI：
10.1111/j.1749-6632.1959.tb49228.x
复制
发表时间：
1959
影响因子：
5.2
通讯作者：
J. Severinghaus
中科院分区：
文献类型：
--
作者：
J. Severinghaus
很明显，在用任何方法快速改变体温时，体内的热梯度都可能很大。这些梯度在选择测温地点、估计停止冷却时温度的超调或“滑行”程度、估计各种组织缺血的安全时间、研究热传递的物理特性以及考虑用冷却的血液灌注时气泡形成的问题等方面都很重要。在本文中，我将以升主动脉血液测量的心脏温度作为核心温度的标准。两个心室的温度相差小于0.08℃。肺温度可以假设等于左心室温度。高灌注的器官，如脑和肾，可能被认为是被动地跟随心脏温度。Bazett3认为外周动脉的血液温度可能是通过与邻近静脉的直接换热而改变的，这种安排构成了一种保温装置。这种逆流交换机制已在许多水生和陆生哺乳动物和鸟类中得到证实。动脉的温度变化不仅取决于回流静脉血的温度，还取决于其他邻近组织的温度和通过动脉的血流速度。
It has become abundantly apparent that thermal gradients within the body can be large during rapid changes of body temperature by any method. These gradients are of importance in selecting a site for temperature measurement, in estimating the degree of overshoot or “coasting” of the temperature when cooling is stopped, in estimating the safe time of ischemia for various tissues, in studies of the physics of heat transfer, and in considering the problem of bubble formation during perfusion with cooled blood. In this paper I shall take the heart temperature, as measured in the blood in the ascending aorta, to be the standard of core temperature. Temperature in the 2 ventricles has been shown to differ’, less than 0.08’C. and lung temperature may be assumed to equal left ventricular temperature. Organs with high perfusion, such as brain and kidney, may be assumed to follow heart temperature passively.Bazett3 suggested that the temperature of blood in the peripheral arteries might be altered by heat exchange directly with the adjacent veins, the arrangement constituting a heat conservation device. This countercurrent exchange mechanism has been demonstrated in many aquatic and terrestrial mammals and birds. 4 The amount of temperature change in the artery depends not only on the temperature of the returning venous blood, but also on the temperature of other adjacent tissues and upon the rate of blood flow through the artery.