Beqiri Erta, Czosnyka Marek, Placek Michal M, Cucciolini Giada, Motroni Virginia, Smith Claudia A, Hutchinson Peter, Smielewski Peter
Brain Physics Laboratory Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge, UK.
Neurosurgery Department, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK.
Brain Spine. 2024 Jan 27;4:102760. doi: 10.1016/j.bas.2024.102760. eCollection 2024.
Continuous monitoring of the pressure reactivity index (PRx) provides an estimation of dynamic cerebral autoregulation (CA) at the bedside in traumatic brain injury (TBI) patients. Visualising the time-trend of PRx with a risk bar chart in ICM + software at the bedside allows for better real-time interpretability of the autoregulation status. When PRx>0.3 is sustained for long periods, typically of at least half an hour, the bar shows a pattern called "red solid line" (RSL). RSL was previously described to precede refractory intracranial hypertension and brain death.
We aimed to describe pathophysiological changes in measured signals/parameters during RSL.
Observation of time-trends of PRx, intracranial pressure, cerebral perfusion pressure, brain oxygenation and compensatory reserve of TBI patients with RSL.
Three pathophysiological patterns were identified: RSL precedes intracranial hypertension, RSL is preceded by intracranial hypertension, or RSL is preceded by brain hypoperfusion. In all cases, RSL was followed by death and the RSL onset was between 1 h and 1 day before the terminal event.
RSL precedes death in intensive care and could represent a marker for terminal clinical deterioration in TBI patients. These findings warrant further investigations in larger cohorts to characterise pathophysiological mechanisms underlying the RSL pattern and whether RSL has a significant relationship with outcome after TBI.
连续监测压力反应性指数（PRx）可在创伤性脑损伤（TBI）患者床边评估动态脑自动调节（CA）。在床边使用ICM +软件中的风险条形图可视化PRx的时间趋势，有助于更好地实时解读自动调节状态。当PRx>0.3持续较长时间，通常至少半小时时，条形图会显示一种称为“红色实线”（RSL）的模式。先前曾描述RSL先于难治性颅内高压和脑死亡出现。
我们旨在描述RSL期间测量信号/参数的病理生理变化。
观察出现RSL的TBI患者的PRx、颅内压、脑灌注压、脑氧合和代偿储备的时间趋势。
确定了三种病理生理模式：RSL先于颅内高压出现、RSL之前存在颅内高压、或RSL之前存在脑灌注不足。在所有病例中，RSL之后均出现死亡，且RSL发作发生在终末事件前1小时至1天之间。
RSL在重症监护中先于死亡出现，可能代表TBI患者终末临床恶化的标志物。这些发现值得在更大队列中进一步研究，以明确RSL模式背后的病理生理机制，以及RSL与TBI后结局是否存在显著关系。
