Sreenan C, Osiovich H, Cheung P Y, Lemke R P
Department of Pediatrics, University of Alberta, Edmonton, Canada.
J Pediatr Surg. 2000 Oct;35(10):1411-4. doi: 10.1053/jpsu.2000.16402.
The aim of this study was to determine whether recirculation could be quantified by a thermodilution technique during venovenous (VV) extracorporeal membrane oxygenation (ECMO) in a rabbit model.
Five New Zealand white rabbits, mean weight, 4.5 (range, 3.7 to 5.7) kg, were anesthetized, instrumented, cannulated with a double-lumen catheter, and placed on VV ECMO. Serial injections of ice-cold saline were performed at the arterial arm of the circuit, and the resultant temperature change at various pump flows was measured at the venous arm of the circuit using a thermistor-tipped catheter and a cardiac output computer. Results were compared with the respective 100% recirculation measured with all the circuit flow passing through the bridge.
Using linear regression, recirculation percentage could be calculated as: 19 + 0.1 x pump flow (R2 = 0.81, P < .005). Recirculation correlated positively with pump flow. Variability between results at each flow was less than 10%.
Recirculation can be quantified during VV ECMO by measuring the change in temperature in the venous arm using a cardiac output computer after injection of a known quantity of ice-cold saline in the arterial side of the circuit. The effect of interventions to reduce recirculation can be assessed conveniently and reliably.
本研究旨在确定在兔模型的静脉-静脉（VV）体外膜肺氧合（ECMO）过程中，是否可以通过热稀释技术对再循环进行量化。
5只新西兰白兔，平均体重4.5（范围3.7至5.7）kg，进行麻醉、仪器植入、用双腔导管插管，并置于VV ECMO上。在回路的动脉端进行一系列冷盐水注射，并使用热敏电阻尖端导管和心输出量计算机在回路的静脉端测量不同泵流量下产生的温度变化。将结果与通过桥接器的所有回路流量测量的各自100%再循环进行比较。
使用线性回归，再循环百分比可计算为：19 + 0.1×泵流量（R2 = 0.81，P <.005）。再循环与泵流量呈正相关。每个流量下结果之间的变异性小于10%。
在回路动脉侧注射已知量的冷盐水后，通过使用心输出量计算机测量静脉端的温度变化，可以在VV ECMO期间对再循环进行量化。可以方便且可靠地评估减少再循环的干预措施的效果。
