Kato J, Seo T, Ando H, Takagi H, Ito T
Department of Surgery, Branch Hospital, Nagoya University School of Medicine, Japan.
J Thorac Cardiovasc Surg. 1996 Mar;111(3):630-6. doi: 10.1016/s0022-5223(96)70315-x.
The effects of venoarterial extracorporeal membrane oxygenation on left ventricular performance have not been studied in detail. Coronary arterial flow obtained by direct measurement with an electromagnetic flowmeter and blood gas analysis from the aortic root were tabulated during venoarterial extracorporeal membrane oxygenation 14 puppies, and these parameters were evaluated with respect to changes in the venoarterial extracorporeal membrane oxygenation flow. Unique automatic blood pumps generating pulsatile flow were used for the venoarterial extracorporeal membrane oxygenation bypass. Coronary arterial flow decreased as the extracorporeal membrane oxygenation flow increased (106 +/- 26 ml/min per 100 gm of left ventricle at 20 ml x min(-1) x kg bypass flow to 71 +/- 17 ml/min per 100 gm of left ventricle at 100 ml x min(-1) x kg bypass flow, p < 0.01). There were no significant changes in the mean or diastolic pressures in the ascending aorta despite changes in the extracorporeal membrane oxygenation flow. Arterial oxygen tension in the ascending aorta was not increased even under high-flow venoarterial extracorporeal membrane oxygenation. This result indicates that oxygenated blood from the extracorporeal membrane oxygenation circuit does not pass in a retrograde fashion into the aortic root and thus does not perfuse the coronary arteries. The diastolic aortic pressure did not correlate with the changes in extracorporeal membrane oxygenation flow. The decrease in coronary arterial flow is therefore predominantly caused by increased coronary arterial resistance. Tension-time index, an indicator of myocardial oxygen consumption, did not decrease with venoarterial extracorporeal membrane oxygenation. In conclusion, high-flow venoarterial extracorporeal membrane oxygenation causes undesirable hemodynamic effects on the left ventricle.
静脉-动脉体外膜肺氧合对左心室功能的影响尚未得到详细研究。在14只幼犬进行静脉-动脉体外膜肺氧合期间，用电磁流量计直接测量获得的冠状动脉血流量以及主动脉根部的血气分析结果被制成表格，并根据静脉-动脉体外膜肺氧合血流量的变化对这些参数进行评估。用于静脉-动脉体外膜肺氧合旁路的是产生搏动血流的独特自动血泵。随着体外膜肺氧合血流量增加，冠状动脉血流量减少（体外膜肺氧合血流量为20 ml·min⁻¹·kg时，每100 g左心室为106±26 ml/min；体外膜肺氧合血流量为100 ml·min⁻¹·kg时，每100 g左心室为71±17 ml/min，p<0.01）。尽管体外膜肺氧合血流量发生变化，但升主动脉的平均压或舒张压无显著变化。即使在高流量静脉-动脉体外膜肺氧合情况下，升主动脉的动脉氧分压也未升高。这一结果表明，来自体外膜肺氧合回路的氧合血不会逆行进入主动脉根部，因此不会灌注冠状动脉。舒张期主动脉压与体外膜肺氧合血流量的变化无关。因此，冠状动脉血流量的减少主要是由冠状动脉阻力增加引起的。心肌耗氧量指标张力-时间指数在静脉-动脉体外膜肺氧合时并未降低。总之，高流量静脉-动脉体外膜肺氧合会对左心室产生不良的血流动力学影响。
