目的:这项研究的重点是评估微中风事件期间关键生理参数的破坏,以评估其严重程度。
方法:建立了数学模型来模拟脑组织pO2,葡萄糖浓度,和血液流动中断导致的温度。该模型考虑了基线脑血流量(CBF)的变化,毛细管密度,和血氧/葡萄糖水平,以及环境温度的变化。
结果:模拟表明,完全的血流阻塞仍然允许有限的葡萄糖供应,支持非氧化代谢并可能加剧乳酸积聚和酸中毒。部分阻塞降低组织pO2,对葡萄糖水平影响最小,可以保持几乎不变,甚至略有增加。降低CBF,毛细管密度,或血氧由于老化或疾病增加缺氧风险在较低的阻塞水平,毛细血管密度通过影响pO2和葡萄糖水平对中风严重程度有显著影响。条件可能导致缺氧/低血糖或缺氧/高血糖的同时发生,每一个恶化的结果。脑深部区域的温度影响很小,但根据环境温度,颅骨附近的温度变化为0.2-0.8°C。
结论:该模型基于估计的缺氧水平提供了对导致严重中风结局的条件的见解,低血糖,高血糖症,和温度变化。
OBJECTIVE: This study focuses on evaluating the disruptions in key physiological parameters during microstroke events to assess their severity.
METHODS: A mathematical model was developed to simulate the changes in cerebral tissue pO2, glucose concentration, and temperature due to blood flow interruptions. The model considers variations in baseline cerebral blood flow (CBF), capillary density, and blood
oxygen/glucose levels, as well as ambient temperature changes.
RESULTS: Simulations indicate that complete blood flow obstruction still allows for limited glucose availability, supporting nonoxidative metabolism and potentially exacerbating lactate buildup and acidosis. Partial obstructions decrease tissue pO2, with minimal impact on glucose level, which can remain almost unchanged or even slightly increase. Reduced CBF, capillary density, or blood
oxygen due to aging or disease enhances hypoxia risk at lower obstruction levels, with capillary density having a significant effect on stroke severity by influencing both pO2 and glucose levels. Conditions could lead to co-occurrence of hypoxia/hypoglycemia or hypoxia/hyperglycemia, each worsening outcomes. Temperature effects were minimal in deep brain regions but varied near the skull by 0.2-0.8°C depending on ambient temperature.
CONCLUSIONS: The model provides insights into the conditions driving severe stroke outcomes based on estimated levels of hypoxia, hypoglycemia, hyperglycemia, and temperature changes.