Department of Neurosurgery.
Department of Intensive Care, University Hospitals Leuven, Leuven, Belgium.
Curr Opin Crit Care. 2023 Apr 1;29(2):85-88. doi: 10.1097/MCC.0000000000001026. Epub 2023 Feb 9.
Severe traumatic brain injury (TBI) remains the most prevalent neurological condition worldwide. Observational and interventional studies provide evidence to recommend monitoring of intracranial pressure (ICP) in all severe TBI patients. Existing guidelines focus on treating elevated ICP and optimizing cerebral perfusion pressure (CPP), according to fixed universal thresholds. However, both ICP and CPP, their target thresholds, and their interaction, need to be interpreted in a broader picture of cerebral autoregulation, the natural capacity to adjust cerebrovascular resistance to preserve cerebral blood flow in response to external stimuli.
Cerebral autoregulation is often impaired in TBI patients, and monitoring cerebral autoregulation might be useful to develop personalized therapy rather than treatment of one size fits all thresholds and guidelines based on unidimensional static relationships.
Today, there is no gold standard available to estimate cerebral autoregulation. Cerebral autoregulation can be triggered by performing a mean arterial pressure (MAP) challenge, in which MAP is increased by 10% for 20 min. The response of ICP (increase or decrease) will estimate the status of cerebral autoregulation and can steer therapy mainly concerning optimizing patient-specific CPP. The role of cerebral metabolic changes and its relationship to cerebral autoregulation is still unclear and awaits further investigation.
严重创伤性脑损伤（TBI）仍然是全球最常见的神经疾病。观察性和干预性研究为推荐所有严重 TBI 患者监测颅内压（ICP）提供了证据。现有的指南侧重于根据固定的通用阈值治疗升高的 ICP 和优化脑灌注压（CPP）。然而，ICP 和 CPP 及其目标阈值及其相互作用需要在脑自动调节的更广泛的背景下进行解释，脑自动调节是一种自然调节脑血管阻力以响应外部刺激来维持脑血流的能力。
TBI 患者的脑自动调节常常受损，监测脑自动调节可能有助于制定个性化治疗方案，而不是根据基于单向静态关系的一刀切的阈值和指南进行治疗。
目前，尚无评估脑自动调节的金标准。脑自动调节可以通过进行平均动脉压（MAP）挑战来触发，其中 MAP 增加 10%持续 20 分钟。ICP 的反应（增加或减少）将估计脑自动调节的状态，并主要指导优化患者特异性 CPP 的治疗。脑代谢变化及其与脑自动调节的关系尚不清楚，有待进一步研究。
