Department of Cardiothoracic Anesthesiology, Heart Centre, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100, Copenhagen, Denmark.
Department of Anesthesiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
J Clin Monit Comput. 2020 Apr;34(2):245-251. doi: 10.1007/s10877-019-00324-w. Epub 2019 May 28.
Near infrared spectroscopy (NIRS) has been used to evaluate regional cerebral tissue oxygen saturation (ScO) during the last decades. Perioperative management algorithms advocate to maintain ScO, by maintaining or increasing cardiac output (CO), e.g. with fluid infusion. We hypothesized that ScO would increase in responders to a standardized fluid challenge (FC) and that the relative changes in CO and ScO would correlate. This study is a retrospective substudy of the FLuid Responsiveness Prediction Using Extra Systoles (FLEX) trial. In the FLEX trial, patients were administered two standardized FCs (5 mL/kg ideal body weight each) during cardiac surgery. NIRS monitoring was used during the intraoperative period and CO was monitored continuously. Patients were considered responders if stroke volume increased more than 10% following FC. Datasets from 29 non-responders and 27 responders to FC were available for analysis. Relative changes of ScO did not change significantly in non-responders (mean difference - 0.3% ± 2.3%, p = 0.534) or in fluid responders (mean difference 1.6% ± 4.6%, p = 0.088). Relative changes in CO and ScO correlated significantly, p = 0.027. Increasing CO by fluid did not change cerebral oxygenation. Despite this, relative changes in CO correlated to relative changes in ScO. However, the clinical impact of the present observations is unclear, and the results must be interpreted with caution.Trial registration:http://ClinicalTrial.gov identifier for main study (FLuid Responsiveness Prediction Using Extra Systoles-FLEX): NCT03002129.
近红外光谱（NIRS）技术已被用于评估过去几十年中局部脑组织氧饱和度（ScO）。围手术期管理算法主张通过维持或增加心输出量（CO）来维持 ScO，例如通过补液。我们假设对标准化液体挑战（FC）有反应的患者 ScO 会增加，并且 CO 和 ScO 的相对变化会相关。本研究是使用额外搏动预测液体反应性（FLEX）试验的回顾性亚研究。在 FLEX 试验中，在心脏手术期间对患者进行了两次标准化 FC（各 5ml/kg 理想体重）。术中使用 NIRS 监测，连续监测 CO。如果 FC 后每搏量增加超过 10%，则认为患者对 FC 有反应。有 29 名非反应者和 27 名 FC 反应者的数据集可供分析。非反应者的 ScO 相对变化没有明显变化（平均差异-0.3%±2.3%，p=0.534）或液体反应者（平均差异 1.6%±4.6%，p=0.088）。CO 和 ScO 的相对变化显著相关，p=0.027。通过补液增加 CO 并没有改变脑氧合。尽管如此，CO 的相对变化与 ScO 的相对变化相关。然而，目前观察结果的临床影响尚不清楚，结果必须谨慎解释。试验注册：http://ClinicalTrial.gov 主研究（使用额外搏动预测液体反应性-FLEX）的标识符：NCT03002129。
