Exploring Cerebrospinal Compensatory Zones Using a Noninvasive Approach.

IF 3.6 3区医学 Q2 CLINICAL NEUROLOGY

Neurocritical Care Pub Date : 2025-07-14 DOI:10.1007/s12028-025-02320-2

Sérgio Brasil, Marek Czosnyka, Wellingson S Paiva, Gustavo Frigieri

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引用次数: 0

Abstract

Background: Intracranial compliance (ICC) reflects the balance among intracranial volume components. Recent technological advances enable continuous, noninvasive assessment of ICC in neurocritical care settings. In this study, we aimed to correlate noninvasive ICC parameters derived from intracranial pressure (ICP) waveform morphology with the established amplitude-pressure index (RAP index), which is calculated using invasive ICP monitoring.

Methods: Patients with traumatic brain injury underwent ventricular ICP monitoring. Simultaneously, ICP values and waveform characteristics were recorded using an external skull microdynamics sensor (brain4care) that provides surrogate waveform parameters, including the P2/P1 ratio and time-to-peak (TTP). The RAP index was calculated using dedicated software based on ICP values and pulse amplitude and was used to categorize patients into three groups: (1) adequate ICC, (2) compromised ICC, and (3) exhausted ICC. Noninvasive parameters (P2/P1 ratio and TTP) were then analyzed in relation to RAP index groupings.

Results: A total of 61 patients were included. Group 1 (adequate ICC) had a median ICP of 12.3 ± 5.4 mm Hg, a P2/P1 ratio of 1.06 ± 0.3, and a TTP of 0.18 ± 0.09 s. Group 2 (compromised ICC) had a median ICP of 13 ± 6.4 mm Hg, a P2/P1 ratio of 1.15 ± 0.32, and a TTP of 0.23 ± 0.07 s. Group 3 (exhausted ICC) had a median ICP of 19.45 ± 5.9 mm Hg, a P2/P1 ratio of 1.31 ± 0.26, and a TTP of 0.25 ± 0.05 s. Regression analysis revealed a statistically significant association between the noninvasive parameters and RAP index-based ICC classification (p < 0.0001).

Conclusions: This study demonstrates a significant correlation between the RAP index and noninvasive ICP waveform-derived parameters, such as the P2/P1 ratio and TTP. These findings suggest that such noninvasive measures may serve as reliable indicators of ICC status. The critical ICP cut-off per RAP was 19.45 mmHg, below the current threshold for therapy escalation according to TBI guidelines. Although further prospective validation is required, this approach has the potential to facilitate earlier intervention before ICC deterioration and enable noninvasive monitoring, possibly improving outcomes in neurocritical care.

Trial registration: NCT03144219. Registered 15 June 2017, http://www.

Clinicaltrials: gov/NCT03144219 .

Clinical trial registration: ClinicalTrials.gov identifier: NCT03144219.

查看原文本刊更多论文

用无创方法探查脑脊髓代偿区。

背景：颅内顺应性（Intracranial compliance， ICC）反映颅内容积成分之间的平衡。最近的技术进步使神经危重症护理环境中ICC的持续、无创评估成为可能。在本研究中，我们旨在将颅内压（ICP）波形形态学得出的无创ICC参数与通过有创ICP监测计算的已建立的振幅-压力指数（RAP指数）相关联。方法：对外伤性脑损伤患者行颅内压监测。同时，使用外部颅骨微动力学传感器（brain4care）记录ICP值和波形特征，该传感器提供替代波形参数，包括P2/P1比和峰值时间（TTP）。RAP指数根据ICP值和脉冲幅度使用专用软件计算，并将患者分为三组：(1)ICC充足，(2)ICC受损，(3)耗尽ICC。然后分析无创参数（P2/P1比率和TTP）与RAP指标分组的关系。结果：共纳入61例患者。1组（适当的ICC）中位ICP为12.3±5.4 mm Hg， P2/P1比值为1.06±0.3，TTP为0.18±0.09 s。2组（ICC受损）中位ICP为13±6.4 mm Hg， P2/P1比值为1.15±0.32，TTP为0.23±0.07 s。第三组（耗尽ICC）中位ICP为19.45±5.9 mm Hg， P2/P1比值为1.31±0.26，TTP为0.25±0.05 s。回归分析显示，无创参数与基于RAP指数的ICC分类之间存在统计学意义上的相关性(p)。结论：本研究表明RAP指数与无创ICP波形衍生参数（如P2/P1比和TTP）之间存在显著相关性。这些发现表明，这种非侵入性措施可以作为ICC状态的可靠指标。根据TBI指南，每个RAP的临界ICP临界值为19.45 mmHg，低于目前治疗升级的阈值。虽然需要进一步的前瞻性验证，但这种方法有可能促进ICC恶化之前的早期干预，并实现无创监测，可能改善神经危重症护理的结果。试验注册：NCT03144219。临床试验注册：ClinicalTrials.gov标识符：NCT03144219。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

Neurocritical Care 医学-临床神经学

CiteScore

7.40

自引率

8.60%

发文量

221

审稿时长

4-8 weeks

期刊介绍： Neurocritical Care is a peer reviewed scientific publication whose major goal is to disseminate new knowledge on all aspects of acute neurological care. It is directed towards neurosurgeons, neuro-intensivists, neurologists, anesthesiologists, emergency physicians, and critical care nurses treating patients with urgent neurologic disorders. These are conditions that may potentially evolve rapidly and could need immediate medical or surgical intervention. Neurocritical Care provides a comprehensive overview of current developments in intensive care neurology, neurosurgery and neuroanesthesia and includes information about new therapeutic avenues and technological innovations. Neurocritical Care is the official journal of the Neurocritical Care Society.