Wang Yunjian, Zhu Liang
Department of Mechanical Engineering, University of Maryland Baltimore County, Baltimore, MD 21250, USA.
Eur J Appl Physiol. 2007 Sep;101(1):31-40. doi: 10.1007/s00421-007-0451-6. Epub 2007 Apr 12.
In this study, the feasibility of a newly developed interstitial cooling device inserted into the neck muscle and placed on the surface of the common carotid artery is evaluated. A combination of vascular model and continuum model is developed to simulate the temperature fields in both the neck and brain regions. Parametric studies are conducted to test the sensitivity of various factors on the temperature distribution. It has been shown that the length of the device, temperature of the device, and the tissue gap between the device and the blood vessel are the dominant factors that determine the effectiveness of this cooling approach. Under the current design parameters, the device is capable of inducing a temperature drop of 2.8 degrees C along the common carotid artery and it results in a total of 90 W of heat carried away from the arterial blood. Although the degree of the cooling in the arterial blood is inversely proportional to the blood flow rate of the arteries, the total heat loss from the arterial blood does not vary significantly if the blood flow rate changes during the cooling. After the cold arterial blood is supplied to the brain hemisphere, temperature reduction in the brain tissue is almost uniform and up to 3.1 degrees C temperature drop is achieved within 1 hour. In addition to the possible benefits of brain hypothermia for stroke or head injury patients, the device has the potential to control fever as well as to improve patients' outcome during open neck and head surgery.
在本研究中，对一种新开发的插入颈部肌肉并放置在颈总动脉表面的间质冷却装置的可行性进行了评估。开发了血管模型和连续体模型的组合，以模拟颈部和脑部区域的温度场。进行了参数研究，以测试各种因素对温度分布的敏感性。结果表明，装置的长度、装置的温度以及装置与血管之间的组织间隙是决定这种冷却方法有效性的主要因素。在当前设计参数下，该装置能够使颈总动脉沿线温度下降2.8摄氏度，并且总共能从动脉血中带走90瓦的热量。尽管动脉血中的冷却程度与动脉血流速度成反比，但如果冷却过程中血流速度发生变化，动脉血的总热损失不会有显著变化。将冷动脉血供应到脑半球后，脑组织中的温度降低几乎是均匀的，并且在1小时内实现了高达3.1摄氏度的温度下降。除了对中风或头部受伤患者进行脑部低温治疗可能带来的益处外，该装置还具有控制发热以及改善颈部和头部开放性手术患者预后的潜力。
