Development of small-caliber vascular grafts for free tissue transfer

本研究报道了直径为1~2 mm的小口径血管移植物的实验研究，可作为肿瘤切除后重建的供体，用于游离组织移植的血管蒂。小直径人工血管由内径1.4 mm、长15 mm的聚氨酯制成，内表面涂有甲基丙烯酸羟乙酯-苯乙烯嵌段共聚物和含有氨甲酸酯的阿加曲班溶液。实验动物为以股动脉和腹壁下动静脉为蒂的腹壁下皮瓣。与位于腹膜后间隙的肾动、静脉吻合。采用人造血管作为皮瓣与肾侧的连接体，行上腹壁皮瓣移植。分别用非涂层和涂层人工血管进行急性实验(n=3)和涂层人工血管慢性实验(n=17)。急性实验中，非涂层人工血管均在3h内血栓形成。慢性实验中，17例中有10例(59%)皮瓣存活1周。动、静脉侧桥均通畅3例。术后1周内，腹膜后皮瓣与受体床之间可见新生血管形成。在这种模型中，移植物只是插入并固定在血管上，人工血管内皮细胞增生导致的血栓形成并被闭塞。然而，它似乎展示了未来的前景，应用小口径人工血管进行游离组织移植，以减少供体部位的牺牲。

This research reported that experimental study of small-caliber vascular grafts shown 1-2mm in diameter could be utilized in the vascular pedicle of the free tissue transfer as a donor for reconstruction after malignant tumor resection. The small-diameter artificial blood vessel was made of the polyurethane (l.4mm inside diameter, 15mm length), and the inner surface was coated with 2-Hydroxyethyl methacrylate-Styrene block-copolymer and Argatroban contained urethane solution. The experimental model in the rabbit was an inferior epigastric flap, which had the vascular pedicle of the femoral and inferior epigastrice artery and vein. And it anastmosed to the renal artery and vein which were located in the retroperitoneal space. The transplantation of the epigastric flap was performed using the artificial vessels as connectors of flap and renal side. The following experiments were done : Acute experiments by non-coated and coated artificial vessls (n=3) and chronic experiments (n=17) by coated grafts. As a result in acute erxperiment, non-coated artificial vessel was thrombosed in all cases within 3 hours. In the chronic experiment, 1 week flap survival existed in 10 flaps (59%) in the 17 cases. The grafts of both artery and venous side were patent in 3 cases. The angiogenesis between the flap and recipient bed of retroperitoneum was observed to occur within on week. Since in this model the graft was just inserted and fixed to the blood vessel, the thrombosis based on the endothelium hyperplasia in artificial blood vessel occurred and occluded. However, it seemed to show the future prospect, which applied small-diameter artificial blood vessels to free tissue transfer in order to decrease the sacrifice of the donor site.