Honjo Osami, Merklinger Sandra L, Poe John B, Guerguerian Anne-Marie, Alghamdi Abdullah A, Takatani Setsuo, Van Arsdell Glen S
The Labatt Family Heart Centre, Hospital for Sick Children and the University of Toronto, Toronto, Ontario, Canada.
J Thorac Cardiovasc Surg. 2009 Feb;137(2):355-61. doi: 10.1016/j.jtcvs.2008.09.036. Epub 2008 Dec 27.
We tested mechanical cavopulmonary blood flow assist by incorporating a novel miniature centrifugal pump into a 1(1/2)-ventricle type cavopulmonary connection in neonatal pigs.
Nine 3-week-old piglets (mean body weight, 10.2 kg) were used: mechanical cavopulmonary assist (n = 6) and controls (n = 3). A bidirectional cavopulmonary connection between the superior vena cava and the main pulmonary artery was created. The superior vena cava and pulmonary artery were also connected by cannulas with an interposed centrifugal pump. The cavoarterial mechanical cavopulmonary assist was performed at pump speeds of 1500, 2000, 2500, and 3000 rpm. Retrograde superior vena caval flow was limited by a band on the superior vena cava. A bidirectional cavopulmonary connection was created in the control animals, which then had a pure 1(1/2)-ventricle repair physiology without mechanical support. Hemodynamics, blood gas, and cerebral blood flow measured by ultrasound were analyzed. Catheter-based dilatation of the surgically created superior vena cava obstruction was tested.
Incremental increases in pump speed augmented bidirectional cavopulmonary shunt blood flow (P =.03) and diminished superior vena caval pressure (P =.03), thereby improving cerebral perfusion pressure. Pump flow of 3000 rpm was equivalent to baseline superior vena caval flow (before caval flow, 392 +/- 48 mL/min vs MCPA, 371 +/- 120 mL/min; mean +/- SD; P = not significant). The mechanical cavopulmonary assist group had higher Doppler velocities of the middle cerebral artery and higher transcerebral oxygen difference(P < .05) than controls. Balloon dilatation of the superior vena cava band was successful.
Mechanical cavopulmonary assist maintained bidirectional cavopulmonary shunt flow, thereby sustaining primary bilateral cavopulmonary shunt physiology in a neonatal pig model of high pulmonary vascular resistance. The mechanical cavopulmonary assist maintained cerebral blood flow and metabolism with an adequate transcerebral pressure gradient.
我们通过将一种新型微型离心泵纳入新生猪的1（1/2）心室型腔肺连接中来测试机械性腔肺血流辅助。
使用9只3周龄仔猪（平均体重10.2千克）：机械性腔肺辅助组（n = 6）和对照组（n = 3）。在上腔静脉和主肺动脉之间建立双向腔肺连接。上腔静脉和肺动脉也通过插管与中间的离心泵相连。以1500、2000、2500和3000转/分钟的泵速进行腔动脉机械性腔肺辅助。上腔静脉血流逆行受上腔静脉上的束带限制。在对照动物中建立双向腔肺连接，然后使其具有无机械支持的单纯1（1/2）心室修复生理状态。分析通过超声测量的血流动力学、血气和脑血流。测试基于导管的手术造成的上腔静脉梗阻扩张情况。
泵速的逐渐增加使双向腔肺分流血流增加（P = 0.03），上腔静脉压力降低（P = 0.03），从而改善了脑灌注压。3000转/分钟的泵流量与上腔静脉基线流量相当（腔静脉血流前，392±48毫升/分钟 vs 平均腔肺分流，371±120毫升/分钟；平均值±标准差；P = 无显著性差异）。机械性腔肺辅助组的大脑中动脉多普勒速度和经脑氧差高于对照组（P < 0.05）。上腔静脉束带的球囊扩张成功。
在高肺血管阻力的新生猪模型中，机械性腔肺辅助维持了双向腔肺分流血流，从而维持了原发性双侧腔肺分流生理状态。机械性腔肺辅助通过适当的经脑压力梯度维持脑血流和代谢。
