Connolly J E
Am J Surg. 1987 Jul;154(1):2-10. doi: 10.1016/0002-9610(87)90282-0.
The historical development of in situ saphenous vein bypass has been traced over the past quarter century. The principal advantage of the in situ vein graft over the conventional reversed vein graft is the increase in flow that occurs in a tapered channel. Both the advantages of this hemodynamic observation in the in situ graft and its disadvantages in the reversed graft are accentuated in longer bypasses as the discrepancy in proximal and distal vein diameter increases. Furthermore, there is new evidence that unusual shear and stress tend to occur at sites of severe vein-artery discrepancy, such as seen in reversed vein grafts but less so in the in situ graft. Experience with the in situ graft has shown that another important advantage is that there is less chance of trauma to the vein from overdistention and rotation, which is inherent in the operation since the vein is not removed from its bed. On the other hand, the overly traumatic disruption of venous valves required in the in situ operation can cause subendothelial damage with resultant fibrosis of the vein. Although it has been demonstrated that equally good results with reversed as with in situ grafts can be obtained by careful attention to detail, this is true only for grafts carried to the popliteal level. The advantages of increased flow and less shear damage because of tapering, physiologic distention under arterial pressure, and finally, decreased handling and manipulation of the vein have become increasingly important as bypass is carried distal to the knee. I believe that the evidence to date indicates that the in situ operation has strong superiority over the conventional reversed graft for reconstructive operations on the lower extremity extending below the knee.
在过去的四分之一个世纪里，人们追溯了原位大隐静脉旁路移植术的历史发展。与传统的倒置静脉移植相比，原位静脉移植的主要优势在于其锥形通道内血流增加。随着旁路移植长度增加，近端和远端静脉直径差异增大，这种血流动力学观察在原位移植中的优势以及在倒置移植中的劣势都更加明显。此外，有新证据表明，在严重的静脉 - 动脉直径差异部位，如倒置静脉移植中所见，但原位移植中较少见，往往会出现异常的剪切力和应力。原位移植的经验表明，另一个重要优势是静脉因过度扩张和旋转而受到创伤的可能性较小，这在手术中是固有的，因为静脉未从其床中取出。另一方面，原位手术中所需的静脉瓣膜过度创伤性破坏会导致内膜下损伤，进而引起静脉纤维化。尽管已经证明，通过仔细关注细节，倒置移植和原位移植都能取得同样好的效果，但这仅适用于移植到腘窝水平的情况。随着旁路移植延伸至膝部以下，由于锥形结构、动脉压力下的生理性扩张以及最终减少对静脉的处理和操作而增加血流和减少剪切损伤的优势变得越来越重要。我认为，迄今为止的证据表明，在膝关节以下的下肢重建手术中，原位手术比传统的倒置移植具有明显的优势。
