Chun Youngjae, Cho Sung Kwon, Clark William C, Wagner William R, Gu Xinzhu, Tevar Amit D, McEnaney Ryan M, Tillman Bryan W
From the Industrial Engineering (Y.C.), Mechanical Engineering & Materials Science (S.K.C., W.C.C.), Department of Bioengineering (W.R.W.), Department of Chemical Engineering (W.R.W.), Swanson School of Engineering, McGowan Institute for Regenerative Medicine (W.R.W., X.G., B.W.T.), University of Pittsburgh; Department of Surgery (A.D.T., R.M.M., B.W.T.), Thomas E. Starzl Transplantation Institute (A.D.T.), and Division of Vascular Surgery (R.M.M., B.W.T.), University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania.
J Trauma Acute Care Surg. 2017 Aug;83(2):249-255. doi: 10.1097/TA.0000000000001534.
Noncompressible hemorrhage of the torso remains a challenging surgical dilemma. Stent graft repair requires endovascular expertise, imaging, and inventory that are not available within the critical window of massive hemorrhage. We developed a retrievable stent graft for rapid hemorrhage. We further investigated a radiofrequency (RF) positioning approach as a possible alternative to the logistics of fluoroscopy.
A retrievable stent graft was constructed with a novel "petal and stem" design from nitinol and covered with a sleeve of electrospun polyurethane. The stent graft was tested using an in vitro model of simulated hemorrhage. Next, the stent graft was examined in vivo using a porcine model of noncompressible hemorrhage. The stent was examined for hemorrhage control in a porcine model of either aortic or caval injury. An RF reader was assembled from an Arduino processor while RF tags were affixed to the ends of the stent graft. Detection accuracy of a handheld RF wand for an RF tag was quantified both in vitro and through tissue.
The retrievable RESCUEstent graft was deployed within minutes and rapidly controlled traumatic hemorrhage angiographically in both aortic injury (n = 3) and caval injury (n = 2). Stent grafts were easily recaptured in both models in under 15 seconds. The LED light of a handheld RF detector illuminated when positioned directly over an RF tag. The RF detection approach revealed positioning accuracy to within 1 cm of the intended target, despite tissue interference.
This study demonstrates the rapid deployment and retrieval of a RESCUE stent graft as well as the ability to tamponade injuries of the aorta and cava. In addition, this study demonstrates the feasibility of RF tags to guide stent placement through tissue. More rigorous models are needed to define the effectiveness of this approach in the setting of vascular injury and shock.
躯干不可压缩性出血仍然是一个具有挑战性的外科难题。支架移植物修复需要血管内专业技术、成像设备和库存，而这些在大出血的关键窗口期内无法获得。我们开发了一种用于快速止血的可回收支架移植物。我们进一步研究了射频（RF）定位方法，作为透视检查后勤工作的一种可能替代方案。
用新型“花瓣和茎”设计由镍钛诺构建一个可回收支架移植物，并用静电纺丝聚氨酯套管覆盖。使用模拟出血的体外模型对支架移植物进行测试。接下来，在猪不可压缩性出血模型中对支架移植物进行体内检查。在主动脉或腔静脉损伤的猪模型中检查支架对出血的控制情况。用Arduino处理器组装一个RF阅读器，同时将RF标签粘贴到支架移植物的末端。在体外和通过组织对手持式RF棒对RF标签的检测准确性进行量化。
可回收的RESCUE支架移植物在数分钟内部署到位，并在主动脉损伤（n = 3）和腔静脉损伤（n = 2）中通过血管造影迅速控制了创伤性出血。在两个模型中，支架移植物在15秒内很容易被回收。当手持式RF探测器直接位于RF标签上方时，其LED灯会亮起。尽管存在组织干扰，但RF检测方法显示定位精度在预期目标的1厘米范围内。
本研究证明了RESCUE支架移植物的快速部署和回收以及压迫主动脉和腔静脉损伤的能力。此外，本研究证明了RF标签通过组织引导支架放置的可行性。需要更严格的模型来确定这种方法在血管损伤和休克情况下的有效性。
