心理负荷的评估:基于神经人因学的视角

心理负荷的评估正经历着从传统工效学向神经人因学的变革.EEG、ERPs、fMRI、fNIRS和TCD等神经科学研究技术为这场变革提供了有力的工具.研究发现:在单任务情境下,随着操作者心理负荷的增加,脑电α波活动减弱,θ波活动增强,并且前额皮层血流、左侧额下回血液氧合血红蛋白浓度变化均增加,大脑动脉血流速度也增快;在双任务情境下,随着操作者主任务心理负荷的增加,次任务的N1、新异P3和P3b等ERPs成分波幅降低.依据这些研究成果,学者们利用人工神经网络、支持向量机等模式分类算法实现了对心理负荷的实时在线评估.但是,各种研究技术在敏感性、诊断力、主任务干扰、实施需求、可接受性和信度等方面各有优势与不足.在未来研究中,要注意促进相关技术的融合、提高其可接受性,并充分利用模式识别算法提高其诊断力和敏感性.     

严重脓毒症——评价指标带给我们的启示

目前,严重脓毒症的诊断指标已对脓毒症导致的临床情况作出较好的诠释,进一步寻找相关的指标将更有助于临床判断。我们评价了血流动力学和组织灌注参数,免疫紊乱、凝血障碍的相关参数以及前降钙素等指标在临床上的价值。目前所采用的一些指标确实有助于严重脓毒症的诊断,但是,我们需要更特异的指标来指导临床工作。     

SLIPA^TM喉罩在眼外科手术中的应用

探讨SLIPA^TM喉罩用于全麻眼外科手术对患者血流动力学、呼吸功能和围术期并发症的影响。60例ASA Ⅰ或Ⅱ级在全麻下实施眼外科手术的患者,随机分为SLIPA^TM通气道组（30例）和气管内插管组（30例）。在麻醉诱导前（T0）、插入SLIPA“通气道／气管导管后即刻（T1）、插入SLIPA^TM通气道／气管导管后5...     

Normalized pulse volume and blood volume as separate indices of finger arterial and venous vascular tone: Examination under propofol

Abstract: This study examined the newly proposed indices for estimating finger vascular tone, which can be obtained from near infrared transmittance photoplethysmographic recordings; normalized pulse volume (NPV) and blood volume (BV). They were recorded for seven male and two female students under continuous infusion of and recovery from propofol. Concomitant hemodynamic measurements were made with a non-invasive impedance cardiograph and a continuous blood pressure monitor. Normalized pulse volume showed no apparent dose-dependency and was negatively correlated with total peripheral resistance. In contrast, BV increased dose-dependently with propofol concentration and was negatively correlated with cardiac preload index (PLI) and with stroke volume (SV) at higher concentrations. The supplementary structural equation modeling procedure effectively illustrated causal relationships between BV, PLI and SV. In conclusion, the present data suggest that NPV and BV independently reflect arterial and venous tone in the finger tip, respectively. Although the underlying mechanisms remain unclear, BV is more sensitive to vascular dilation under propofol anesthesia.