Hernandez-Meza Gabriela, Izzetoglu Meltem, Sacan Ahmet, Green Michael, Izzetoglu Kurtulus
Drexel University, School of Biomedical Engineering, Science and Health Systems, Philadelphia, Pennsylvania, United States.
Drexel University College of Medicine, Hahnemann University Hospital, Department of Anesthesiology, Philadelphia, Pennsylvania, United States.
Neurophotonics. 2017 Oct;4(4):041408. doi: 10.1117/1.NPh.4.4.041408. Epub 2017 Aug 19.
Anesthesia monitoring currently needs a reliable method to evaluate the effects of the anesthetics on its primary target, the brain. This study focuses on investigating the clinical usability of a functional near-infrared spectroscopy (fNIRS)-derived machine learning classifier to perform automated and real-time classification of maintenance and emergence states during sevoflurane anesthesia. For 19 surgical procedures, we examine the entire continuum of the maintenance-transition-emergence phases and evaluate the predictive capability of a support vector machine (SVM) classifier during these phases. We demonstrate the robustness of the predictions made by the SVM classifier and compare its performance with that of minimum alveolar concentration (MAC) and bispectral (BIS) index-based predictions. The fNIRS-SVM investigated in this study provides evidence to the usability of the fNIRS signal for anesthesia monitoring. The method presented enables classification of the signal as maintenance or emergence automatically as well as in real-time with high accuracy, sensitivity, and specificity. The features local mean HbTotal, std [Formula: see text], local min Hb and [Formula: see text], and range Hb and [Formula: see text] were found to be robust biomarkers of this binary classification task. Furthermore, fNIRS-SVM was capable of identifying emergence before movement in a larger number of patients than BIS and MAC.
目前,麻醉监测需要一种可靠的方法来评估麻醉剂对其主要作用目标——大脑的影响。本研究重点探讨基于功能近红外光谱(fNIRS)的机器学习分类器在七氟烷麻醉期间对维持期和苏醒期进行自动实时分类的临床实用性。对于19例外科手术,我们研究了维持-过渡-苏醒阶段的整个连续过程,并评估了支持向量机(SVM)分类器在这些阶段的预测能力。我们展示了SVM分类器预测的稳健性,并将其性能与基于最低肺泡浓度(MAC)和脑电双频指数(BIS)的预测性能进行比较。本研究中所研究的fNIRS-SVM为fNIRS信号用于麻醉监测的实用性提供了证据。所提出的方法能够自动且实时地将信号准确分类为维持期或苏醒期,具有高准确性、敏感性和特异性。发现局部平均总血红蛋白(HbTotal)、标准差[公式:见原文]、局部最小血红蛋白和[公式:见原文]以及血红蛋白范围和[公式:见原文]这些特征是该二元分类任务的稳健生物标志物。此外,与BIS和MAC相比,fNIRS-SVM能够在更多患者中在运动出现之前识别出苏醒。