Lam J M, Hsiang J N, Poon W S
Department of Surgery, Prince of Wales Hospital, Chinese University of Hong Kong, Shatin, Hong Kong.
J Neurosurg. 1997 Mar;86(3):438-45. doi: 10.3171/jns.1997.86.3.0438.
The authors studied 31 comatose head-injured patients to assess the clinical usefulness of laser Doppler flowmetry (LDF) in continuous autoregulation monitoring. The LDF probes were placed on the surface of the cerebral cortex. Data on LDF, intracranial pressure (ICP), and arterial blood pressure (ABP) were recorded and continuously entered into a computer. The data were broken down into multiple segments of 15 minutes' duration (epochs). Epochs showing rapid change in cerebral perfusion pressure (CPP), change in CPP of less than 10 mm Hg, LDF values of less than five arbitrary units, and loss of ABP/ICP waveform were excluded from further analysis. A linear relationship between LDF and CPP in individual epochs was used as an indicator of loss of autoregulation. The relationship between LDF and CPP changed with time, indicating improvement or deterioration in autoregulation. Longitudinal analysis of all the epochs measured in a patient revealed three patterns of progress: 1) intact autoregulation; 2) transient loss; and 3) persistent loss of autoregulation. All five patients with intact autoregulation had a good outcome. Ten patients experienced transient loss of autoregulation; of these four had a good outcome, five were moderately disabled and one was severely disabled. Transient impairment of autoregulation did not always indicate poor outcome, provided the impaired autoregulation responded to treatment. In 11 patients who had persistent loss of autoregulation, nine died and two were severely disabled. In five cases the LDF probe lost contact with the cerebral cortex and no useful information was obtained. Real-time measurement of autoregulation using LDF and CPP monitors was achieved and the findings were related to outcome in these patients.
作者研究了31例昏迷的头部受伤患者，以评估激光多普勒血流仪（LDF）在连续自动调节监测中的临床实用性。LDF探头放置在大脑皮层表面。记录LDF、颅内压（ICP）和动脉血压（ABP）的数据，并持续输入计算机。数据被分解为持续15分钟的多个时间段（时段）。显示脑灌注压（CPP）快速变化、CPP变化小于10 mmHg、LDF值小于五个任意单位以及ABP/ICP波形消失的时段被排除在进一步分析之外。各个时段中LDF与CPP之间的线性关系被用作自动调节丧失的指标。LDF与CPP之间的关系随时间变化，表明自动调节功能改善或恶化。对患者测量的所有时段进行纵向分析，揭示了三种进展模式：1）自动调节功能完整；2）短暂丧失；3）自动调节功能持续丧失。所有五名自动调节功能完整的患者预后良好。十名患者经历了自动调节功能的短暂丧失；其中四名预后良好，五名中度残疾，一名重度残疾。只要受损的自动调节功能对治疗有反应，自动调节功能的短暂损害并不总是预示着不良预后。在11名自动调节功能持续丧失的患者中，9名死亡，2名重度残疾。有5例LDF探头与大脑皮层失去接触，未获得有用信息。实现了使用LDF和CPP监测器对自动调节功能的实时测量，并且这些结果与这些患者的预后相关。
