Section of Neurosurgery, Department of Medical Sciences, Uppsala University, 751 85, Uppsala, Sweden.
Department of Surgical Sciences/Anesthesia and Intensive Care, Uppsala University, 751 85, Uppsala, Sweden.
J Clin Monit Comput. 2023 Feb;37(1):319-326. doi: 10.1007/s10877-022-00894-2. Epub 2022 Jul 17.
Higher intracranial pressure variability (ICPV) has been associated with a more favorable cerebral energy metabolism, lower rate of delayed ischemic neurologic deficits, and more favorable outcome in aneurysmal subarachnoid hemorrhage (aSAH). We have hypothesized that higher ICPV partly reflects more compliant and active cerebral vessels. In this study, the aim was to further test this by investigating if higher ICPV was associated with lower cerebrovascular resistance (CVR) and higher cerebral blood flow (CBF) after aSAH. In this observational study, 147 aSAH patients were included, all of whom had been treated in the Neurointensive Care (NIC) Unit, Uppsala, Sweden, 2012-2020. They were required to have had ICP monitoring and at least one xenon-enhanced computed tomography (Xe-CT) scan to study cortical CBF within the first 2 weeks post-ictus. CVR was defined as the cerebral perfusion pressure in association with the Xe-CT scan divided by the concurrent CBF. ICPV was defined over three intervals: subminute (ICPV-1m), 30-min (ICPV-30m), and 4 h (ICPV-4h). The first 14 days were divided into early (days 1-3) and vasospasm phase (days 4-14). In the vasospasm phase, but not in the early phase, higher ICPV-4h (β = - 0.19, p < 0.05) was independently associated with a lower CVR in a multiple linear regression analysis and with a higher global cortical CBF (r = 0.19, p < 0.05) in a univariate analysis. ICPV-1m and ICPV-30m were not associated with CVR or CBF in any phase. This study corroborates the hypothesis that higher ICPV, at least in the 4-h interval, is favorable and may reflect more compliant and possibly more active cerebral vessels.
颅内压变异性（ICPv）较高与更好的脑能量代谢、较低的迟发性缺血性神经功能缺损发生率和更好的颅内动脉瘤性蛛网膜下腔出血（aSAH）预后相关。我们假设，较高的 ICPv 部分反映了更具顺应性和更活跃的脑血管。在这项研究中，我们旨在通过研究 ICPv 是否与 aSAH 后较低的脑血管阻力（CVR）和较高的脑血流（CBF）相关来进一步检验这一假设。
在这项观察性研究中，纳入了 147 名 aSAH 患者，他们均于 2012 年至 2020 年在瑞典乌普萨拉的神经重症监护病房（NIC）接受治疗。他们必须接受 ICP 监测，并至少在发病后 2 周内进行一次氙增强 CT（Xe-CT）扫描以研究皮质 CBF。CVR 定义为与 Xe-CT 扫描相关的脑灌注压除以同时的 CBF。
ICPv 在三个时间段内定义：亚分钟（ICPv-1m）、30 分钟（ICPv-30m）和 4 小时（ICPv-4h）。前 14 天分为早期（第 1-3 天）和血管痉挛期（第 4-14 天）。在血管痉挛期，而不是在早期，较高的 ICPv-4h（β=-0.19，p<0.05）在多元线性回归分析中与较低的 CVR 独立相关，在单变量分析中与较高的全局皮质 CBF（r=0.19，p<0.05）相关。在任何阶段，ICPv-1m 和 ICPv-30m 均与 CVR 或 CBF 无关。
这项研究证实了这样的假设，即较高的 ICPv（至少在 4 小时的间隔内）是有利的，可能反映了更具顺应性和可能更活跃的脑血管。
