Department of Intensive Care, Erasme University Hospital, Université Libre de Brussels, Route de Lennik, 808 1070, Brussels, Belgium.
Brain Physics Laboratory, Department of Clinical Neurosciences, Addenbrooke's Hospital, University of Cambridge, Hills Rd, Cambridge CB2 0QQ, United Kingdom.
Clin Neurol Neurosurg. 2021 Mar;202:106478. doi: 10.1016/j.clineuro.2021.106478. Epub 2021 Jan 8.
Adequate cerebral perfusion prevents secondary insult after traumatic brain injury (TBI). Cerebral autoregulation (CAR) keeps cerebral blood flow (CBF) constant when arterial blood pressure (ABP) changes. Aim of the study was to evaluate the existence of delayed CAR in TBI patients and its possible association with outcome.
We retrospectively analysed TBI patients. Flow velocity (FV) in middle cerebral artery, invasive intra-cranial pressure (ICP) and ABP were recorded. Cerebral perfusion pressure (CPP) was calculated as ABP - ICP. Mean flow index (Mx) > 0.3 defined altered CAR. Samples from patients with altered CAR were further analysed: FV signal was shifted backward relative to CPP; Mx was calculated after each shift (MxD). Mx > 0.3 plus MxD ≤ 0.3 defined delayed CAR. Favourable outcome (FO) at 6 months was defined as Glasgow Outcome Scale 4-5.
154 patients were included. GCS was 6 [4-9], ICP was 14 [9-20] mmHg. Data on 6 months outcome were available for 131 patients: 104/131 patients (79 %) were alive; GOS was 4 [3-5]; 70/131 (53 %) had FO. Mx was 0.07 [-0.19 to 0.28] overall. Mx was lower in patients with FO compared others (0.00 [-0.21 to 0.20] vs 0.17 [-0.12 to 0.37], p = 0.02). 118 (77 %) patients had intact CAR and 36 (23 %) patients had altered CAR; 23 patients - 15 % of the general cohort and 64 % of patients with altered CAR - had delayed CAR. Delay in the autoregulatory response was 2 [1-4] seconds. 80/98 (82 %) of patients with intact CAR survived, compared to 16/21 (76 %) with delayed and 8/12 (67 %) with altered CAR (p = 0.20). 80/98 (58 %) patients with intact, 10/21 (48 %) patients with delayed and 3/12 (25 %) patients with altered CAR had FO (p = 0.03).
A subgroup of TBI patients with delayed CAR was identified. Delayed CAR was associated with better neurological outcome than altered CAR.
颅脑损伤（TBI）后，充分的脑灌注可预防继发性损伤。脑自动调节（CAR）可在动脉血压（ABP）变化时保持脑血流（CBF）恒定。本研究旨在评估 TBI 患者 CAR 是否存在延迟及其与预后的可能相关性。
我们回顾性分析了 TBI 患者。记录大脑中动脉的血流速度（FV）、有创颅内压（ICP）和 ABP。脑灌注压（CPP）计算为 ABP - ICP。平均流量指数（Mx）> 0.3 定义为 CAR 改变。对存在 CAR 改变的患者进一步分析：FV 信号相对于 CPP 后移；每次移位后计算 Mx（MxD）。Mx > 0.3 加 MxD ≤ 0.3 定义为延迟 CAR。6 个月时的良好预后（FO）定义为格拉斯哥预后量表 4-5 分。
共纳入 154 例患者。GCS 为 6 [4-9]，ICP 为 14 [9-20]mmHg。131 例患者的 6 个月预后数据可用：104/131 例（79%）存活；GOS 为 4 [3-5]分；70/131 例（53%）预后良好。整体 Mx 为 0.07 [-0.19 至 0.28]。FO 患者的 Mx 低于其他患者（0.00 [-0.21 至 0.20] vs 0.17 [-0.12 至 0.37]，p = 0.02）。118 例（77%）患者存在完整的 CAR，36 例（23%）患者存在 CAR 改变；23 例（15%的总体队列和 64%的 CAR 改变患者）患者存在延迟 CAR。自动调节反应延迟 2 [1-4] 秒。完整 CAR 组 80/98 例（82%）患者存活，延迟 CAR 组 16/21 例（76%）和 CAR 改变组 8/12 例（67%）存活（p = 0.20）。完整 CAR 组 80/98 例（58%）、延迟 CAR 组 10/21 例（48%）和 CAR 改变组 3/12 例（25%）患者预后良好（FO）（p = 0.03）。
确定了 TBI 患者存在 CAR 延迟的亚组。与 CAR 改变相比，CAR 延迟与更好的神经功能预后相关。
