Etz D C, Luehr M, Aspern K V, Misfeld M, Gudehus S, Ender J, Koelbel T, Debus E S, Mohr F-W
Department of Cardiac Surgery, Leipzig Heart Center University of Leipzig, Leipzig, Germany -
J Cardiovasc Surg (Torino). 2014 Apr;55(2 Suppl 1):159-68.
For more than half a century ischemic spinal cord injury (SCI) and consecutively permanent paraplegia remained the most devastating complication after open and endovascular thoracoabdominal aortic aneurysm (TAAA) repair. Various neuroprotective strategies (e.g., motor-/somatosensory evoked potential monitoring and cerebrospinal fluid drainage) used as adjuncts have lowered the SCI; maybe most importantly, the modern collateral network (CN) has begun to replace the classic understanding of spinal cord blood supply implying several consequences. Reliable non-invasive tools to monitor cord perfusion to detect imminent spinal cord malperfusion, ischemia and forthcoming neurologic injury (particularly early postoperatively) is not available, neither is a reliable strategy to prevent ischemic injury during distal circulatory arrest and after segmental artery occlusion. Currently, two promising new concepts--potentially advancing spinal protection in open and endovascular TAAA repair--address these issues: 1) non-invasive real-time monitoring of the paraspinous CN-oxygenation via near-infrared spectroscopy (NIRS) as an alternative to the demanding direct neuromonitoring; and 2) preconditioning of the CN as minimally invasive, endovascular "first stage" to increase the resilience of spinal cord perfusion prior to definite aortic repair. This article illustrates both concepts discussing: 1) the clinical application of thoracic and lumbar collateral NIRS monitoring to indirectly detect spinal cord hypoperfusion; and 2) minimally invasive selective segmental artery coil-embolization (MISACE) for (arteriogenic) preconditioning of the CN prior to extensive open or endovascular staged TAAA repair.
半个多世纪以来，缺血性脊髓损伤（SCI）以及随之而来的永久性截瘫一直是开放性和血管腔内胸腹主动脉瘤（TAAA）修复术后最具破坏性的并发症。作为辅助手段使用的各种神经保护策略（如运动/体感诱发电位监测和脑脊液引流）降低了SCI的发生率；也许最重要的是，现代侧支循环网络（CN）已开始取代对脊髓血液供应的传统认识，这意味着一些后果。目前还没有可靠的非侵入性工具来监测脊髓灌注以检测即将发生的脊髓灌注不良、缺血和即将出现的神经损伤（尤其是术后早期），也没有可靠的策略来预防远端循环阻断期间和节段动脉闭塞后发生的缺血性损伤。目前，有两个有前景的新概念——可能在开放性和血管腔内TAAA修复中推进脊髓保护——解决了这些问题：1）通过近红外光谱（NIRS）对椎旁CN氧合进行非侵入性实时监测，作为要求较高的直接神经监测的替代方法；2）将CN预处理作为微创血管腔内“第一阶段”，以增加在确定性主动脉修复之前脊髓灌注的弹性。本文阐述了这两个概念，讨论了：1）胸腰段侧支NIRS监测在临床中的应用，以间接检测脊髓灌注不足；2）在广泛的开放性或血管腔内分期TAAA修复之前，对CN进行（动脉源性）预处理的微创选择性节段动脉线圈栓塞术（MISACE）。
