Perthel M, Kseibi S, Sagebiel F, Alken A, Laas J
Department of Cardiothoracic Surgery, Herz- und Gefässzentrum Bad Bevensen, Bad Bevensen, Germany.
Perfusion. 2005 Oct;20(6):329-33. doi: 10.1191/0267659105pf828oa.
The intention of minimal extracorporeal circulation (MECC) is to reduce priming volume and minimize contact of blood with polymers and air in a closed system. In contrast to conventional extracorporeal circulation (ECC), a venous reservoir is missing. Thus, air trapping is limited and avoidance of bubble embolism is a major concern. This study investigates microbubbles (MBB) number and size in the venous and arterial lines of ECC and MECC compared to the number of microembolic signals (MES) in the right and left middle cerebral artery (MCA). Twenty patients undergoing coronary surgery were operated either with conventional ECC (cardiotomy reservoir, Rotaflow pump, Quadrox oxygenator, Quart filter) or MECC (Quart filter, Rotaflow pump, Quadrox oxygenator). Number and size of MBB were monitored in the venous and arterial lines with an ultrasound Doppler system. MES in right and left MCAs were measured by transcranial Doppler (TCD) monitoring. Patients undergoing MECC had additional sealing of the venous cannula by a ligature at the site of its insertion into the right atrium. There were no significant differences between groups with respect to age, X-clamping, bypass time and number of distal anastomoses. The number of MES and MBB in the arterial line was comparable between the groups. On the venous side, MECC-perfusion shows a significantly lower number of MBB. This could be explained with the additional sealing of the venous cannula. Furthermore, our data indicate that the MBB-volume reaching the pump will also appear in the arterial outflow and into the patient's MCA. For this reason, the avoidance of air contamination is a major concern for surgeons, anaesthesiologists and perfusionists.
微创体外循环（MECC）的目的是减少预充量，并在封闭系统中尽量减少血液与聚合物和空气的接触。与传统体外循环（ECC）相比，MECC没有静脉储血器。因此，空气捕获受到限制，避免气泡栓塞是一个主要问题。本研究调查了ECC和MECC的静脉和动脉管路中的微泡（MBB）数量和大小，并与左右大脑中动脉（MCA）中的微栓塞信号（MES）数量进行比较。20例接受冠状动脉手术的患者分别采用传统ECC（心内直视手术储血器、Rotaflow泵、Quadrox氧合器、Quart过滤器）或MECC（Quart过滤器、Rotaflow泵、Quadrox氧合器）进行手术。使用超声多普勒系统监测静脉和动脉管路中的MBB数量和大小。通过经颅多普勒（TCD）监测测量左右MCA中的MES。接受MECC的患者在静脉插管插入右心房的部位通过结扎进行额外密封。两组在年龄、X夹闭、体外循环时间和远端吻合数量方面无显著差异。两组动脉管路中的MES和MBB数量相当。在静脉侧，MECC灌注显示MBB数量显著减少。这可以用静脉插管的额外密封来解释。此外，我们的数据表明，到达泵的MBB体积也会出现在动脉流出道和患者的MCA中。因此，避免空气污染是外科医生、麻醉师和灌注师的主要关注点。
