Greim C A, Roewer N, Thiel H, Laux G, Schulte am Esch J
Department of Anesthesiology, Julius-Maximilians-Universität, Würzburg, Germany.
Anesth Analg. 1997 Sep;85(3):483-8. doi: 10.1097/00000539-199709000-00003.
Continuous thermodilution (CT) using a pulmonary artery (PA) catheter with a thermal filament has the potential for intraoperative on-line monitoring of cardiac output. Liver transplantation frequently requires rapid fluid administration and often includes the use of an extracorporeal veno-venous bypass. To assess the agreement between CT and bolus thermodilution (BT) in such a setting, we conducted a prospective intraoperative study in 14 liver transplant patients. Throughout the operation, CT cardiac output was recorded and paired with BT measurements taken every 30 min and whenever indicated for clinical reason. Corresponding data were assigned to acquisition periods when patients were on or off veno-venous bypass (flow rate 2.5 +/- 0.2 L/min) and were discriminated by the various range of intravenous infusion rates (< 150 mL/h, 150-1000 mL/h, 1000-2000 mL/h, and 2000-4000 mL/h) and the magnitude of cardiac output (< or = 7.5 L/min, 7.5-10.0 L/min, > 10.0 L/min). A total of 270 data pairs was obtained and examined by analysis of agreement (mean difference +/- SD), variance, error, and weighted regression. Trend analysis was performed for significant CT and BT cardiac output changes, defined as changes greater than 15%. Agreement of both methods was best at peripheral intravenous fluid infusion rates < or = 1000 mL/h and BT cardiac output > 10 L/min (0.0 +/- 0.6 L/min) and was unaffected by veno-venous bypass. Discrepancy was most evident at intravenous fluid infusion rates > 2000 mL/h and BT cardiac output < or = 7.5 L/min (2.1 +/- 1.7 L/min). Correlation of CT and BT cardiac output was excellent (r = 0.95, P < 0.001) for combined data from all patients. Changes in CT cardiac output > 15% (n = 116) correctly indicated the direction in 93% of BT cardiac output changes and were 74% sensitive and 75% specific for significant BT cardiac output changes. The thermal filament technique enhances the usefulness of PA catheterization during liver transplantation but reflects BT cardiac output with clinically acceptable error only at low peripheral intravenous fluid infusion rates.
Cardiac output determines organ perfusion. In clinical practice, it is measured by intermittent thermodilution using right heart catheterization. This intraoperative study compared the intermittent method with a technique based on continuous thermodilution. The new technique provides logistical advantages and challenges the accuracy of the intermittent method during liver transplantation.
使用带有热丝的肺动脉导管进行连续热稀释（CT）有潜力在术中在线监测心输出量。肝移植经常需要快速补液，且常使用体外静脉 - 静脉旁路。为评估在这种情况下CT与团注热稀释（BT）之间的一致性，我们对14例肝移植患者进行了一项前瞻性术中研究。在整个手术过程中，记录CT心输出量，并与每30分钟以及因临床原因指示时进行的BT测量值配对。相应数据被分配到患者处于或不处于静脉 - 静脉旁路（流速2.5±0.2 L/min）的采集时间段，并根据不同的静脉输注速率范围（<150 mL/h、150 - 1000 mL/h、1000 - 2000 mL/h和2000 - 4000 mL/h）以及心输出量大小（≤7.5 L/min、7.5 - 10.0 L/min、>10.0 L/min）进行区分。共获得270对数据，并通过一致性分析（平均差异±标准差）、方差、误差和加权回归进行检查。对定义为变化大于15%的显著CT和BT心输出量变化进行趋势分析。两种方法的一致性在周围静脉输液速率≤1000 mL/h且BT心输出量>10 L/min时最佳（0.0±0.6 L/min），且不受静脉 - 静脉旁路影响。差异在静脉输液速率>2000 mL/h且BT心输出量≤7.5 L/min时最为明显（2.1±1.7 L/min）。对于所有患者的合并数据，CT和BT心输出量的相关性极佳（r = 0.95，P < 0.001）。CT心输出量变化>15%（n = 116）在93%的BT心输出量变化中正确指示了方向，对于显著的BT心输出量变化，其敏感性为74%，特异性为75%。热丝技术增强了肝移植期间肺动脉导管插入术的实用性，但仅在低周围静脉输液速率下以临床可接受的误差反映BT心输出量。
心输出量决定器官灌注。在临床实践中，它通过右心导管插入术的间歇性热稀释来测量。这项术中研究将间歇性方法与基于连续热稀释的技术进行了比较。新技术提供了后勤优势，并对肝移植期间间歇性方法的准确性提出了挑战。
