Sistino J J, Michler R E, Mongero L B
Columbia-Presbyterian Medical Center, New York 10032.
J Extra Corpor Technol. 1993;24(4):116-9.
We have explored the potential advantages of a low prime closed-circuit cardiopulmonary bypass (CPB) system using a non-human primate model. Although manufacturers have reduced priming volumes in individual CPB components, the standard circuit volume remains high because of the tubing diameter and length necessary for gravity drainage. By replacing gravity drainage with the negative pressure generated by a centrifugal pump, we can realize significant tubing volume reduction. Closed-circuit bypass was conducted on 13 baboons ranging from 5-15 kg. The circuit consisted of a centrifugal pump, a hollow fiber oxygenator, and 1/4" arterial and venous tubing. The design of the circuit included the capacity to remove a limited amount of venous air. Circulatory arrest during deep hypothermia with volume displacement into a reservoir was also accomplished with this circuit. The potential benefits of this low prime closed-circuit bypass system include blood conservation and reduction in blood surface area contact. The future safe clinical use of this type of closed-circuit bypass for routine open heart surgery will depend upon the incorporation of a device in the venous line to remove air. This is the greatest threat to patient safety in a closed circuit system and its use for open chest surgery must wait until an efficient venous air elimination device is available.
我们使用非人灵长类动物模型探究了低预充量闭合回路体外循环（CPB）系统的潜在优势。尽管制造商已降低了单个CPB组件的预充量，但由于重力引流所需的管道直径和长度，标准回路体积仍然很大。通过用离心泵产生的负压取代重力引流，我们可以显著减少管道体积。对13只体重在5 - 15千克的狒狒进行了闭合回路旁路手术。该回路由一台离心泵、一个中空纤维氧合器以及1/4英寸的动静脉管道组成。回路设计具备去除有限量静脉空气的能力。通过该回路还实现了在深度低温下进行循环停止并将血液容量置换到储血器中。这种低预充量闭合回路旁路系统的潜在益处包括节约血液以及减少血液与表面积的接触。这种类型的闭合回路旁路在常规心脏直视手术中的未来安全临床应用将取决于在静脉管路中加入一个去除空气的装置。这是闭合回路系统中对患者安全的最大威胁，并且在高效的静脉空气消除装置可用之前，其用于开胸手术必须等待。
