Novel method for intraoperative assessment of cerebral autoregulation by paced breathing
Novel method for intraoperative assessment of cerebral autoregulation by paced breathing
复制标题
术中通过定速呼吸评估脑自动调节的新方法
DOI：
10.1093/bja/aex333
复制
发表时间：
2017
期刊：
影响因子：
--
通讯作者：
R. V. Immink
中科院分区：
文献类型：
--
作者：
N. S. Weiland;J. Hermanides;M. Hollmann;B. Preckel;W. Stok;J. J. V. Lieshout;J. J. V. Lieshout;R. V. Immink
背景
脑自动调节（CA）是一种在血压（BP）变化的情况下维持脑血流量（CBF）恒定的机制。研究表明，CA 减弱的患者围手术期中风的发生率增加。对麻醉受试者进行 CA 的研究很少，因为没有一种简单且非侵入性的方法来量化 CA 的完整性。在这项研究中，我们着手改进手术期间 CA 的无创定量。为此，我们引入了一种新方法，通过以三种不同频率施加机械正压通气来放大手术期间的自发血压波动，并量化由此产生的血压波动的 CA。
方法
该研究包括 14 名接受七氟醚麻醉的患者。手术前以 6、10 和 15 bpm 的节奏呼吸 3 分钟，以及手术期间以相同频率的机械正压通气获得连续无创血压和经颅多普勒 CBF 速度 (CBF V )。使用频域分析对数据进行分析，以获得 CBF V 至 BP 相位超前，作为 CA 功效的连续测量。计算组平均值。数值为平均值（sd），P<0.05用于表示统计显着性。
结果
术前与术中 CBF V 至 BP 相位导联在 6、10 和 15bpm 期间分别为 43（9）vs 45（8）°、25（8）vs 24（10）°、4（6）vs -2（12）°（所有 P = NS）。
结论
手术期间，脑自动调节指数与手术前测定的值相似。这表明使用这种新方法可以可靠且非侵入性地量化 CA，并证实了 CA 不受七氟醚麻醉影响的早期证据。
临床试验注册
NCT03071432。
Background
Cerebral autoregulation (CA) is the mechanism that maintains constancy of cerebral blood flow (CBF) despite variations in blood pressure (BP). Patients with attenuated CA have been shown to have an increased incidence of peri-operative stroke. Studies of CA in anaesthetized subjects are rare, because a simple and non-invasive method to quantify the integrity of CA is not available. In this study, we set out to improve non-invasive quantification of CA during surgery. For this purpose, we introduce a novel method to amplify spontaneous BP fluctuations during surgery by imposing mechanical positive pressure ventilation at three different frequencies and quantify CA from the resulting BP oscillations.
Methods
Fourteen patients undergoing sevoflurane anaesthesia were included in the study. Continuous non-invasive BP and transcranial Doppler-derived CBF velocity (CBF V ) were obtained before surgery during 3 min of paced breathing at 6, 10, and 15 bpm and during surgery from mechanical positive pressure ventilation at identical frequencies. Data were analysed using frequency domain analysis to obtain CBF V -to-BP phase lead as a continuous measure of CA efficacy. Group averages were calculated. Values are means ( sd ), and P <0.05 was used to indicate statistical significance.
Results
Preoperative vs intraoperative CBF V -to-BP phase lead was 43 (9) vs 45 (8)°, 25 (8) vs 24 (10)°, and 4 (6) vs -2 (12)° during 6, 10, and 15 bpm, respectively (all P =NS).
Conclusions
During surgery, cerebral autoregulation indices were similar to values determined before surgery. This indicates that CA can be quantified reliably and non-invasively using this novel method and confirms earlier evidence that CA is unaffected by sevoflurane anaesthesia.
Clinical trial registration
NCT03071432.
影响因子：
8.3
作者：
TIECKS, FP;LAM, AM;NEWELL, DW
通讯作者：
NEWELL, DW