目的利用磁吻合技术,研制一套适用于离体肝切除术中快速建立静脉转流的装置,并实验测试其性能及临床应用价值。方法以钕铁硼永磁材料制成磁环,并将其与带有肝素涂层的高分子聚氯乙烯管道连接成“Y”形转流装置。10只实验犬模拟离体肝切除全过程。术中利用磁吻合技术完成静脉转流装置与静脉的吻合,建立体内静脉转流。记录转流建立的时间;彩色多普勒测定术前及术中各静脉血流速、计算转流量;检测术中无肝期血流动力学(颈动脉压、中心静脉压、门静脉压)以及肠管、肾组织变化。结果术中用静脉转流装置在6~10min内即可建立静脉转流,无肝期动物血流动力学稳定,术前静脉流速与术中静脉流速比较无统计学差异(P〉0.05),门静脉和下腔静脉转流率分别为75.5%和76.2%,明显减轻内脏淤血。结论采用磁吻合技术可明显缩短离体肝切除术中静脉转流建立所需时间。动物实验证明快速静脉转流装置在无肝期可有效进行静脉转流,维持血液动力学稳定。
Objective To invent a set of novel veno-venous bypass (VVB) device based on mag- netic anastomosis technique which can be used in ex situ liver resection, and verify its clinical value and per- formance in animal models. Methods Each VVB device was constructed using three magnetic rings and an inverted Y-shaped tube with magnetic rings on each end. The magnetic ring was made of NdFeB with elec- trode cutting, and the tube was made of polyvinyl chloride ( PVC ) and preconditioned with heparin coating on the surface of the lumen. Ten dogs underwent the ex situ liver resection, and VVB was established via magnetic anastomosis technique with the novel VVB device during the operation. The time for completing VVB was recorded, and the hemodynamic indexes including the venous flow velocity, carotid pressure, cen- tral venous pressure and portal pressure was detected. The changes of intestinal lumen and kidney were also observed. Results It only took 6 - 10 minutes to establish VVB by the novel VVB device in the operation, and the hemodynamics stability was maintained smoothly during the anheptic phase. The shunt index of infe- rior vena cava and portal vein was 76.2% and 75.5% , respectively. The congestion of intestinal canal and kidney were also alleviated during the anheptic phase. Conclusions It could reduce the time to establish VVB with magnetic anastomosis technique in ex situ liver resection. This study showed that utilizing the no- vel VVB device for intraabdominal VVB during the anheptie phase could be helpful to maintain the hemody- namics stability.