Deriu G P, Milite D, Mellone G, Cognolato D, Frigatti P, Grego F
Padua Medical School, Italy.
J Cardiovasc Surg (Torino). 1999 Apr;40(2):249-55.
Shunt insertion during carotid endarterectomy (CEA) is mandatory to avoid neurological damage due to clamping ischemia; however shunt insertion before plaque removal has many inconveniences (atheroembolism, intimal dissection, difficulty of endarterectomy). The aim of this study is to verify whether and how long shunt insertion may be safely delayed to permit plaque removal and ensure cerebral perfusion during the further time consuming manoeuvres of CEA (peeling, patch angioplasty).
From July 1990 to February 1996 383 patients underwent 411 CEAs under general anesthesia with EEG continuous monitoring and PTFE patch angioplasty. A Pruitt-Inahara shunt was routinely inserted only after atherosclerotic plaque removal. In 316 CEAs (76.9%) without EEG signs of cerebral ischemia (Group A) the mean clamping time was 10 min +/-4.8 (range 2-37 min). In 95 CEAs (23.1%) with EEG signs of cerebral ischemia (Group B) it was 7.3 min +/-3.5 (range 3-20 min). All patients had normal EEG signals after delayed shunt insertion and reperfusion (mean 21 min, range 5-45 min).
In the short term results (within 30 days) there was a relevant neurological complication rate of 0.96% (2 major stroke and 2 lethal stroke); at awakening we observed 5 RINDs (1.21% of total) 1 in a patient of Group A (0.31%) and the other 4 in patients of Group B (4.21%).
These data confirm the rationale of a delayed insertion of the shunt: actually the cerebral parenchyma may tolerate under general anesthesia a sufferance due to carotid clamping, EEG detectable, without neurological deficits for at least 7.3 min. This time is sufficient to perform the most difficult steps of CEA (plaque removal, distal intima checking) allowing shunt insertion in a clean operatory field, without inconveniences. Finally the shunt allows complementary time consuming steps, as patch angioplasty, with improvement of both short- and long-term results.
颈动脉内膜切除术（CEA）期间插入分流管对于避免因夹闭缺血导致的神经损伤是必不可少的；然而，在去除斑块之前插入分流管有许多不便之处（动脉粥样硬化栓塞、内膜剥离、内膜切除术困难）。本研究的目的是验证分流管插入是否可以安全延迟以及延迟多长时间，以便在CEA后续耗时的操作（剥离、补片血管成形术）过程中去除斑块并确保脑灌注。
1990年7月至1996年2月，383例患者在全身麻醉下接受了411例CEA手术，并进行脑电图连续监测和聚四氟乙烯补片血管成形术。仅在去除动脉粥样硬化斑块后常规插入普鲁伊特-伊纳哈拉分流管。在316例（76.9%）无脑电图脑缺血征象的CEA手术（A组）中，平均夹闭时间为10分钟±4.8（范围2 - 37分钟）。在95例（23.1%）有脑电图脑缺血征象的CEA手术（B组）中，平均夹闭时间为7.3分钟±3.5（范围3 - 20分钟）。所有患者在延迟插入分流管和再灌注后（平均21分钟，范围5 - 45分钟）脑电图信号均正常。
在短期结果（30天内）中，相关神经并发症发生率为0.96%（2例严重中风和2例致命中风）；苏醒时，我们观察到5例可逆性缺血性神经功能障碍（RINDs，占总数的1.21%），其中1例在A组患者中（0.31%），另外4例在B组患者中（4.21%）。
这些数据证实了延迟插入分流管的合理性：实际上，脑实质在全身麻醉下可能耐受因颈动脉夹闭导致的、脑电图可检测到的、至少7.3分钟无神经功能缺损的耐受情况。这段时间足以完成CEA最困难的步骤（去除斑块、检查远端内膜），从而在清洁的手术视野中插入分流管，而不会带来不便。最后，分流管允许进行诸如补片血管成形术等耗时的补充步骤，从而改善短期和长期结果。
