Neurocritical Care Unit, Department of Neurosurgery and Institute of Intensive Care Medicine, Clinical Neuroscience Center, University Hospital Zurich and University of Zurich, Zurich, Switzerland.
Neurocritical Care Unit, Department of Neurosurgery and Institute of Intensive Care Medicine, Clinical Neuroscience Center, University Hospital Zurich and University of Zurich, Zurich, Switzerland.
J Neurosci Methods. 2024 Jun;406:110113. doi: 10.1016/j.jneumeth.2024.110113. Epub 2024 Mar 25.
Detection of delayed cerebral ischemia (DCI) is challenging in comatose patients with poor-grade aneurysmal subarachnoid hemorrhage (aSAH). Brain tissue oxygen pressure (PbtO2) monitoring may allow early detection of its occurrence. Recently, a probe for combined measurement of intracranial pressure (ICP) and intraparenchymal near-infrared spectroscopy (NIRS) has become available. In this pilot study, the parameters PbtO2, Hboxy, Hbdeoxy, Hbtotal and rSO2 were measured in parallel and evaluated for their potential to detect perfusion deficits or cerebral infarction.
In patients undergoing multimodal neuromonitoring due to poor neurological condition after aSAH, Clark oxygen probes, microdialysis and NIRS-ICP probes were applied. DCI was suspected when the measured parameters in neuromonitoring deteriorated. Thus, perfusion CT scan was performed as follow up, and DCI was confirmed as perfusion deficit. Median values for PbtO2, Hboxy, Hbdeoxy, Hbtotal and rSO2 in patients with perfusion deficit (Tmax > 6 s in at least 1 vascular territory) and/or already demarked infarcts were compared in 24- and 48-hour time frames before imaging.
Data from 19 patients (14 University Hospital Zurich, 5 Charité Universitätsmedizin Berlin) were prospectively collected and analyzed. In patients with perfusion deficits, the median values for Hbtotal and Hboxy in both time frames were significantly lower. With perfusion deficits, the median values for Hboxy and Hbtotal in the 24 h time frame were 46,3 [39.6, 51.8] µmol/l (no perfusion deficits 53 [45.9, 55.4] µmol/l, p = 0.019) and 69,3 [61.9, 73.6] µmol/l (no perfusion deficits 74,6 [70.1, 79.6] µmol/l, p = 0.010), in the 48 h time frame 45,9 [39.4, 51.5] µmol/l (no perfusion deficits 52,9 [48.1, 55.1] µmol/l, p = 0.011) and 69,5 [62.4, 74.3] µmol/l (no perfusion deficits 75 [70,80] µmol/l, p = 0.008), respectively. In patients with perfusion deficits, PbtO2 showed no differences in both time frames. PbtO2 was significantly lower in patients with infarctions in both time frames. The median PbtO2 was 17,3 [8,25] mmHg (with no infarctions 29 [22.5, 36] mmHg, p = 0.006) in the 24 h time frame and 21,6 [11.1, 26.4] mmHg (with no infarctions 31 [22,35] mmHg, p = 0.042) in the 48 h time frame. In patients with infarctions, the median values of parameters measured by NIRS showed no significant differences.
The combined NIRS-ICP probe may be useful for early detection of cerebral perfusion deficits and impending DCI. Validation in larger patient collectives is needed.
在昏迷且颅内压增高的自发性蛛网膜下腔出血患者中，迟发性脑缺血（DCI）的检测具有挑战性。脑组织氧压（PbtO2）监测可能有助于早期发现其发生。最近，一种可同时测量颅内压（ICP）和脑实质近红外光谱（NIRS）的探头已经问世。在这项初步研究中，同时测量了 PbtO2、Hboxy、Hbdeoxy、Hbtotal 和 rSO2 等参数，并评估了它们检测灌注不足或脑梗死的潜力。
在因颅内压增高而导致神经功能状况不佳的自发性蛛网膜下腔出血患者中，应用 Clark 氧探头、微透析和 NIRS-ICP 探头进行多模式神经监测。当神经监测中的测量参数恶化时，怀疑发生 DCI。因此，进行了灌注 CT 扫描作为后续检查，DCI 被证实为灌注不足。在成像前 24 小时和 48 小时时间框架内，比较了有灌注不足（至少 1 个血管区域 Tmax > 6 s）和/或已明确梗死的患者的 PbtO2、Hboxy、Hbdeoxy、Hbtotal 和 rSO2 的中位数。
前瞻性收集并分析了 19 名患者（苏黎世大学医院 14 名，柏林 Charité 大学医院 5 名）的数据。在灌注不足的患者中，Hbtotal 和 Hboxy 的中位数在两个时间框架内均显著降低。在 24 小时时间框架内，Hboxy 和 Hbtotal 的中位数在灌注不足的患者中分别为 46.3 [39.6, 51.8] µmol/L（无灌注不足的患者为 53 [45.9, 55.4] µmol/L，p = 0.019）和 69.3 [61.9, 73.6] µmol/L（无灌注不足的患者为 74.6 [70.1, 79.6] µmol/L，p = 0.010），在 48 小时时间框架内，Hboxy 和 Hbtotal 的中位数分别为 45.9 [39.4, 51.5] µmol/L（无灌注不足的患者为 52.9 [48.1, 55.1] µmol/L，p = 0.011）和 69.5 [62.4, 74.3] µmol/L（无灌注不足的患者为 75 [70,80] µmol/L，p = 0.008）。在灌注不足的患者中，PbtO2 在两个时间框架内均无差异。在两个时间框架内，有梗死的患者 PbtO2 明显较低。24 小时时间框架内 PbtO2 的中位数为 17.3 [8,25] mmHg（无梗死的患者为 29 [22.5, 36] mmHg，p = 0.006），48 小时时间框架内 PbtO2 的中位数为 21.6 [11.1, 26.4] mmHg（无梗死的患者为 31 [22,35] mmHg，p = 0.042）。在有梗死的患者中，NIRS 测量的参数的中位数没有显著差异。
联合 NIRS-ICP 探头可能有助于早期发现脑灌注不足和即将发生的 DCI。需要在更大的患者群体中进行验证。
