Lewis Philip M, Smielewski Peter, Rosenfeld Jeffrey V, Pickard John D, Czosnyka Marek
Department of Neurosurgery, Alfred Hospital, Prahran, Australia.
Acta Neurochir Suppl. 2012;114:141-6. doi: 10.1007/978-3-7091-0956-4_26.
Phase shift (PS) between oscillations in arterial blood pressure (ABP) and transcranial Doppler (TCD) cerebral blood flow velocity (CBFV) is thought to describe cerebral autoregulation. Ventilated patients show high amplitude and regular respiratory oscillations in ABP and CBFV, allowing reliable PS measurement. We analysed recordings of ABP, CBFV and intracranial pressure (ICP) from 187 TBI patients treated at Addenbrooke's Hospital, Cambridge, UK, from 1993 to 1998. Monitored data were recorded and PS, TCD autoregulation (Mx) and pressure reactivity (PRx) were calculated using ICM+. PS was computed by peak detection in the ABP/CBFV cross-spectrum. Recordings with low coherence (<0.5), unstable respiratory rate (RR), or PS wraparound were excluded. Median RR was 14 bpm (range 10-20 bpm). Group median PS was 13° (range -37-56°). Average PS (PSa) correlated with RR (Spearman's R = -0.302, p < 0.01, and cerebral perfusion pressure (R = -0.373, p < 0.01). Correlations of PS with Mx and PRx were weak but significant (p < 0.01). Kruskal-Wallis test for outcome vs. PS was non-significant (PSa: p = 0.14, minimum PS (PSm): p = 0.27). Mann-Whitney test for mortality vs. PS was significant (p < 0.05) for PSm only. Respiratory PS responds to changes in CPP and RR and correlates weakly with CA. Respiratory PS may have some prognostic value for patients with TBI.
动脉血压（ABP）振荡与经颅多普勒（TCD）脑血流速度（CBFV）之间的相位偏移（PS）被认为可描述脑自动调节功能。通气患者的ABP和CBFV会出现高振幅且规则的呼吸振荡，这使得可靠的PS测量成为可能。我们分析了1993年至1998年期间在英国剑桥阿登布鲁克医院接受治疗的187例创伤性脑损伤（TBI）患者的ABP、CBFV和颅内压（ICP）记录。记录监测数据，并使用ICM +计算PS、TCD自动调节功能（Mx）和压力反应性（PRx）。通过ABP/CBFV交叉谱中的峰值检测来计算PS。排除相干性低（<0.5）、呼吸频率（RR）不稳定或PS环绕的记录。RR中位数为14次/分钟（范围为10 - 20次/分钟）。组中位数PS为13°（范围为 - 37 - 56°）。平均PS（PSa）与RR相关（斯皮尔曼相关系数R = - 0.302，p < 0.01），与脑灌注压相关（R = - 0.373，p < 0.01）。PS与Mx和PRx的相关性较弱但具有显著性（p < 0.01）。Kruskal - Wallis检验结果与PS的关系无显著性（PSa：p = 0.14，最小PS（PSm）：p = 0.27）。Mann - Whitney检验死亡率与PS的关系仅在PSm时具有显著性（p < 0.05）。呼吸PS对脑灌注压（CPP）和RR的变化有反应，与脑自动调节功能（CA）的相关性较弱。呼吸PS可能对TBI患者具有一定的预后价值。
