Laboratory for Clinical Cardiovascular Physiology, Department of Medical Biology, section Systems Physiology, Academic Medical Center, University of Amsterdam, The Netherlands.
Department of Pulmonary Diseases, VU University Medical Center, Amsterdam, The Netherlands.
Anaesthesia. 2018 Dec;73(12):1489-1499. doi: 10.1111/anae.14380. Epub 2018 Aug 3.
While haemodynamic variability interferes with the assumption of constant flow underlying thermodilution cardiac output calculation, variability in (peripheral) arterial vascular physiology may affect pulse contour cardiac output methods. We compared non-invasive finger arterial pressure-derived continuous cardiac output measurements (Nexfin ) with cardiac output measured using thermodilution during cardiothoracic surgery and determined the impact of cardiovascular variability on either method. We compared cardiac output derived from non-invasive finger arterial pressure with cardiac output measured by thermodilution at four grades (A-D) of cardiovascular variability. We defined Grade A data as heart rate and mean arterial pressure variability < 5% and the absence of arrhythmias (implying stable flow) and Physiocal interval (as measure of variability in finger arterial physiology) > 30 beats. Grade B included all levels of heart rate/mean arterial pressure variability and arrhythmias (Physiocal < 30 excluded). Grade C included all Physiocal intervals (heart rate/mean arterial pressure variability > 5% and arrhythmias excluded). Grade D included all data. Comparison results were quantified as percentage errors. We analysed measurements in 27 patients undergoing coronary artery bypass surgery. Before extracorporeal circulation, the percentage error was 23% (n = 14 patients) in grade A, 28% (n = 20) in grade B, 32% (n = 22) in grade C and 37% (n = 26) in grade D, with a significant increase in variance (p = 0.035). Bias did not differ between grades. After extracorporeal circulation (n = 27), percentage errors became larger, but were not different between grades. Variability during cardiothoracic surgery affected the comparison between thermodilution and non-invasive finger arterial pressure-derived cardiac output. When the main sources of variability were included, percentage errors were large. Future cardiac output methodology comparison studies should report haemodynamic variability.
虽然血流动力学变异性干扰了热稀释心输出量计算中恒定流量的假设，但（外周）动脉血管生理学的变异性可能会影响脉搏轮廓心输出量方法。我们比较了非侵入性手指动脉压力衍生的连续心输出量测量（Nexfin）与心胸外科手术期间使用热稀释测量的心输出量，并确定心血管变异性对这两种方法的影响。我们比较了非侵入性手指动脉压力衍生的心输出量与热稀释测量的心输出量，心血管变异性分为四个等级（A-D）。我们将心率和平均动脉压变异性<5%且无心律失常（表示稳定流量）和 Physiocal 间隔（作为手指动脉生理学变异性的测量）>30 次的心输出量数据定义为 A 级。B 级包括所有心率/平均动脉压变异性和心律失常水平（排除 Physiocal <30）。C 级包括所有 Physiocal 间隔（排除心率/平均动脉压变异性>5%和心律失常）。D 级包括所有数据。比较结果以百分比误差表示。我们分析了 27 例接受冠状动脉旁路移植手术的患者的测量值。在体外循环之前，A 级的百分比误差为 23%（n=14 例患者），B 级为 28%（n=20 例患者），C 级为 32%（n=22 例患者），D 级为 37%（n=26 例患者），方差显著增加（p=0.035）。等级之间的偏差没有差异。体外循环后（n=27），百分比误差变大，但等级之间没有差异。心胸外科手术期间的变异性影响了热稀释与非侵入性手指动脉压力衍生的心输出量之间的比较。当包括主要的变异性来源时，百分比误差较大。未来的心输出量方法比较研究应报告血流动力学变异性。
