Division of Neonatology, Department of Maternal and Perinatal Center, Saitama Children's Medical Center, 1-2 Shintoshin, Chuo, Saitama, 330-8777, Japan.
Eur J Pediatr. 2023 Jun;182(6):2821-2832. doi: 10.1007/s00431-023-04969-3. Epub 2023 Apr 12.
Unstable cerebral blood flow is theorised to contribute to the occurrence of intraventricular haemorrhage (IVH) in extremely low-birth-weight infants (ELBWIs), which can be caused by increased arterial flow, increased venous pressure, and impaired autoregulation of brain vasculature. As a preliminary step to investigate such instability, we aimed to check for correlations of cerebral blood volume (CBV), as measured using near-infrared spectroscopy, with the flow velocities of the anterior cerebral artery (ACA) and internal cerebral vein (ICV), as measured using Doppler ultrasonography. Data were retrospectively analysed from 30 ELBWIs uncomplicated by symptomatic patent ductus arteriosus, which can influence ACA velocity, and severe IVH (grade ≥ 3), which can influence ICV velocity and CBV. The correlation between tissue oxygen saturation (StO and mean blood pressure was also analysed as an index of autoregulation. CBV was not associated with ACA velocity; however, it was significantly correlated with ICV velocity (Pearson R = 0.59 [95% confidence interval: 0.29-0.78], P = 0.00061). No correlation between StO and mean blood pressure was observed, implying that autoregulation was not impaired. Conclusion: Although our findings are based on the premise that cerebral autoregulation was unimpaired in the ELBWIs without complications, the same result cannot be directly applied to severe IVH cases. However, our results may aid future research on IVH prediction by investigating the changes in CBV when severe IVH occurs during ICV velocity fluctuation. What is Known: • The pathogenesis of IVH includes unstable cerebral blood flow affected by increased arterial flow, increased venous pressure, and impaired cerebral autoregulation. • The approaches that can predict IVH are under discussion. What is New: • ACA velocity is not associated with CBV, but ICV velocity is significantly correlated with CBV. • CBV measured using NIRS may be useful in future research on IVH prediction.
不稳定的脑血流被认为是导致极低出生体重儿（ELBWIs）发生脑室内出血（IVH）的原因，这种不稳定可能是由于动脉血流增加、静脉压升高和脑血管自动调节受损引起的。作为研究这种不稳定性的初步步骤，我们旨在检查使用近红外光谱测量的脑血容量（CBV）与使用多普勒超声测量的大脑前动脉（ACA）和大脑内静脉（ICV）的血流速度之间的相关性。对 30 例未合并症状性动脉导管未闭（可影响 ACA 速度）和严重 IVH（等级≥3）（可影响 ICV 速度和 CBV）的 ELBWIs 的数据进行了回顾性分析。还分析了组织氧饱和度（StO）和平均血压之间的相关性，作为自动调节的指标。CBV 与 ACA 速度无关，但与 ICV 速度显著相关（Pearson R=0.59[95%置信区间：0.29-0.78]，P=0.00061）。未观察到 StO 和平均血压之间的相关性，这意味着自动调节没有受损。结论：尽管我们的研究结果基于无并发症的 ELBWIs 中脑自动调节未受损的前提，但这一结果不能直接应用于严重 IVH 病例。然而，我们的结果可能有助于通过研究严重 IVH 期间 ICV 速度波动时 CBV 的变化来研究 IVH 预测的未来研究。已知：• IVH 的发病机制包括受动脉血流增加、静脉压升高和脑自动调节受损影响的不稳定脑血流。• 正在讨论预测 IVH 的方法。新内容：• ACA 速度与 CBV 无关，但 ICV 速度与 CBV 显著相关。• 使用 NIRS 测量的 CBV 在未来 IVH 预测研究中可能有用。
