Interventional Neuroradiology, NEURI Center, Bicêtre Hospital, Le Kremlin- Bicêtre, France.
New England Center for Stroke Research, Department of Radiology, University of Massachusetts Medical School, Worcester, Massachusetts, USA.
J Neurointerv Surg. 2020 Feb;12(2):209-213. doi: 10.1136/neurintsurg-2019-015179. Epub 2019 Jul 30.
The neuroprotective benefit of therapeutic hypothermia (TH) has been demonstrated, but systemic side effects and time required to achieve effective TH in acute ischemic stroke (AIS) care limits clinical use. We investigate rapid and localized cooling using a novel insulated catheter in an ischemia-reperfusion model.
In phase I (n=4), cold saline was delivered to the canine internal carotid artery via an insulated catheter. Temperature was measured using intracerebral thermocouples. The coolant flow rate was varied to meet a target temperature of 31-32°C in the hemisphere infused. In phase II (n=8), a temporary middle cerebral artery occlusion was created. Five dogs underwent localized TH at the optimal flow rate from phase I, and the remaining animals were untreated controls. Cooling was initiated 5 min before recanalization and continued for an additional 20 min following 45 min of occlusion duration. The outcome was infarct volume and neurological function.
Ipsilateral tissue cooling rates were 2.2±2.5°C/min at a flow rate of 20-40 mL/min with an observed minimum of 23.8°C. Tissue cooling was localized to the ipsilateral side of the infusion with little impact on temperatures of the core or contralateral hemisphere of the brain. In phase II, animals tolerated TH with minimal systemic impact. Infarct volume in treated animals was 0.2±0.2 cm, which was smaller than in sham animals (3.8±1.0 cm) as well as six untreated historical control animals (4.0±2.8 cm) (p=0.013).
Proof-of-concept data show that localised brain TH can be quickly and safely achieved through a novel insulated catheter. The small infarct volumes suggest potential benefit for this approach.
治疗性低温（TH）的神经保护益处已得到证实，但在急性缺血性脑卒中（AIS）治疗中，全身副作用和达到有效 TH 所需的时间限制了其临床应用。我们在缺血再灌注模型中使用新型隔热导管研究了快速和局部冷却。
在第一阶段（n=4）中，通过隔热导管将冷盐水输送到犬的颈内动脉。使用颅内热电偶测量温度。改变冷却剂流速以达到半球输注的目标温度 31-32°C。在第二阶段（n=8），创建了临时大脑中动脉闭塞。五只狗在第一阶段的最佳流速下进行局部 TH，其余动物作为未治疗的对照。在再通前 5 分钟开始冷却，并在闭塞持续 45 分钟后继续冷却 20 分钟。结果是梗塞体积和神经功能。
在流速为 20-40ml/min 时，同侧组织冷却速率为 2.2±2.5°C/min，观察到的最低温度为 23.8°C。组织冷却局限于输注的同侧，对核心或大脑对侧半球的温度影响很小。在第二阶段，动物耐受 TH 的全身影响很小。治疗动物的梗塞体积为 0.2±0.2cm，明显小于假手术动物（3.8±1.0cm）和六只未治疗的历史对照动物（4.0±2.8cm）（p=0.013）。
概念验证数据表明，通过新型隔热导管可以快速、安全地实现局部脑 TH。较小的梗塞体积表明这种方法有潜在的益处。
