Barker J H, Anderson G L, Gu J M, Wyllie F, Acland R D
Department of Surgery, University of Louisville, School of Medicine, KY 40292.
Microsurgery. 1993;14(6):409-15. doi: 10.1002/micr.1920140612.
It is generally believed that alterations in perfusion which endanger a free flap or replant are directly related to thrombus formation and obstruction of blood flow at the anastomotic site. Recent experimental work in our laboratory suggests that the presence of platelet emboli downstream in the microcirculation might be responsible at least in part for postoperative perturbations in perfusion. To determine whether changes in tissue perfusion can occur in the absence of corresponding changes in anastomotic patency we studied microvascular blood flow in the exposed rat cremaster flap model. We made continuous measurements of both anastomotic patency and downstream microcirculatory perfusion following small vessel repair. Using this approach we found that during one hour after clamp release and reperfusion in the 10 animals studied, pedicle artery blood pressure, which indicates pedicle patency in this model, was functionally normal 97% +/- 2 of the time while blood flow in the downstream tissue (cremaster) remained normal an average of only 65% +/- 7 of the time. In most cases these flow alterations were associated with the presence of visible platelet emboli in the microcirculation. From these studies we conclude that when flap perfusion failure temporarily occurs, a microsurgeon must consider not only the anastomosis but also the downstream microcirculation when searching for a possible cause.
一般认为，危及游离皮瓣或再植组织的灌注改变与血栓形成及吻合口处血流阻塞直接相关。我们实验室最近的实验工作表明，微循环下游存在血小板栓子可能至少部分导致了术后灌注紊乱。为了确定在吻合口通畅性无相应改变的情况下组织灌注是否会发生变化，我们在暴露的大鼠提睾肌皮瓣模型中研究了微血管血流。在小血管修复后，我们对吻合口通畅性和下游微循环灌注进行了连续测量。采用这种方法，我们发现在所研究的10只动物中，在松开血管夹并再灌注后的1小时内，在此模型中指示蒂部通畅性的蒂动脉血压在97%±2的时间内功能正常，而下游组织（提睾肌）中的血流平均仅在65%±7的时间内保持正常。在大多数情况下，这些血流改变与微循环中可见的血小板栓子的存在有关。从这些研究中我们得出结论，当皮瓣灌注失败暂时发生时，显微外科医生在寻找可能的原因时，不仅必须考虑吻合口，还必须考虑下游微循环。
