Rapid brain cooling method for acute cerebral ischemia・focal cerebral cooling by cold crystaloid intra-arterial perfusion in canine-

目的：脑低温是最有效的神经保护剂。然而，全身低温可能导致致命的并发症。假设在维持正常核心温度的同时进行选择性脑冷却将能够实现局部低温神经保护，而没有全身低温的压力和副作用。因此，我们开发了一种新的方法，通过该方法可以通过动脉内灌注冷晶体溶液来实现快速和选择性地降低脑温度。方法：实验在6只成年健康比格犬（体重10.2-11.4kg）上进行，并按照实验动物护理和使用的机构政策和指南进行。经4Fr导管以1.5- 2.0ml/min/kg的速率动脉内输注冷却至4 ℃的林格氏液。用血液滤过系统抽出过量的水。双侧脑组织温度、直肠温度、中心静脉温度、脑组织氧分压 ...更多信息 连续测量尿素和心输出量。10周后处死几只狗，进行病理学研究。结果：灌注23.3±7.7min，脑组织温度降至28 ℃，可维持106± 13.7min。将对侧脑温、体核温降至34 ℃以下。通过血液滤过抽出相同量的灌注液。体循环动脉压、心率、心脏指数无明显波动。病理结果显示无任何缺血性损害的病理。结论：结果表明，动脉内冷晶体灌注是一种可行的选择性脑低温治疗方法，且靶区温度易于控制。低温的诱导是快速的，并维持了很长一段时间，而体温保持在正常范围内，没有血流动力学不稳定。这种方法使我们能够选择性地，快速和安全地冷却大脑的目标区域。该方法可用于急性脑损伤、缺血或难治性癫痫。少

Purpose: Cerebral hypothermia is the most potent neuroprotectant. Nevertheless, systemic hypothermia may result in fatal complication. It is hypothesized that selective cerebral cooling while maintaining normal core temperature would enable local hypothermic neuroprotection without the stress and side effects of systemic hypothermia. Thus, we have developed a novel method by which the rapid and selective reduction of brain temperature could achieve by intra-arterial perfusing cold crystalloid solution. Method: The experiments were performed on six adult healthy beagle dogs, weighting 10.2-11.4kg, and conducted in accordance with institutional Policies and Guidelines for Care and Use of Laboratory Animals. Ringer's solution cooled to 4 degree centigrade was infused by 1.5-2.0 ml/min/kg via 4Fr catheter intra-arterially. Excessive water was drawn out with hemo-filtration system. Bilateral brain tissue temperatures, rectal temperature, central venous temperature, brain tissue oxygen press … More ure and cardiac output were measured continuously. Several dogs were killed 10 weeks later and pathologically investigated. Results: The brain tissue temperature was fallen into 28 degree centigrade by perfusion for 23.3±7.7min and could be maintained for 106± 13.7min. The contra-lateral brain temperature, core temperature were cooled into less than 34 degree centigrade. The same quantity of perfusate was drawn out by hemo-filtration. The systemic arterial pressure, heart rate and cardiac index were not fluctuated. Pathological findings revealed not any ischemic damages pathologically. Conclusions: The data demonstrated that the intra-arterial cold crystalloid perfusion was technically feasible and useful for selective brain hypothermia, and target temperature are easily controlled. The induction of hypothermia was rapid and maintained for a long period of time, whereas the body temperature was maintained within the normal range and without hemodynamic instability. This method enables us to cool the objective region of the brain selectively, rapidly and safely. This method may useful for acute brain damages, ischemia or refractory epilepsy. Less