Aleksic M, Heckenkamp J, Gawenda M, Reichert V, Brunkwall J
Division of Vascular Surgery, Department of Visceral- and Vascular Surgery, University Clinic of Cologne, Germany.
Eur J Vasc Endovasc Surg. 2007 Nov;34(5):540-5. doi: 10.1016/j.ejvs.2007.05.020. Epub 2007 Jul 9.
Induced hypertension is widely recommended as a protective measure in carotid endarterectomy (CEA) to prevent shunt insertion. In this study changes of systemic blood pressure were evaluated in relation to the shunt rate when CEA was performed under local anaesthesia.
In 930 CEAs performed for a high-grade (>70%) ICA stenosis under local anaesthesia the mean systemic blood pressure was measured preoperatively (RR1) and directly before carotid cross-clamping (RR2). A ratio was calculated from these values (RRR=RR2/RR1). A shunt was only inserted for clinical signs of cerebral ischemia. If that became necessary later after cross-clamping had been tolerated primarily, the blood pressure during this period was also recorded (RR3). Also the presence of a contralateral ICA occlusion and baseline blood pressure levels were considered as factors with potential impact on shunt necessity.
Among the 638 male (69%) and 292 female (31%) patients with a median age of 70 years (ranging from 52 to 91 years) 82 (9%) had a contralateral ICA occlusion. A shunt was used in 177 operations (19%) and significantly more frequent in patients with a contralateral ICA occlusion (39/82=48% vs. 138/848=16%, p<0,001). RRR was significantly reduced in patients who needed a shunt (0.95 (0.41-1.53) vs. 1.0 (0.54-1.9), p=0.002) which was only true for patients with a patent contralateral ICA. The shunt rate did not differ when contrasting RRR thresholds (<0.7 vs. >1.3) or preoperative blood pressure levels (<100 mmHg vs. >120 mmHg) were compared. RRR did not differ between directly or delayed shunted patients. RR3 did not differ significantly from RR2. A regression analysis identified the presence of a contralateral ICA occlusion as the only independent parameter influencing shunt insertion.
Changes in systemic blood pressure during CEA under local anaesthesia seem to influence shunting rather marginally. The value of induced hypertension to prevent cerebral ischemia should be newly discussed.
诱导性高血压作为颈动脉内膜切除术（CEA）中预防分流管插入的一种保护措施被广泛推荐。在本研究中，对局部麻醉下行CEA时全身血压的变化与分流率的关系进行了评估。
在930例因颈内动脉（ICA）重度（>70%）狭窄而在局部麻醉下进行的CEA手术中，术前（RR1）及即将进行颈动脉交叉阻断前（RR2）测量平均全身血压。根据这些值计算一个比值（RRR=RR2/RR1）。仅在出现脑缺血临床体征时插入分流管。如果在最初耐受交叉阻断后后来有必要插入分流管，则记录此期间的血压（RR3）。此外，将对侧ICA闭塞的存在及基线血压水平视为对分流必要性有潜在影响的因素。
在638例男性（69%）和292例女性（31%）患者中，中位年龄为70岁（范围52至91岁），82例（9%）存在对侧ICA闭塞。177例手术（19%）使用了分流管，在对侧ICA闭塞患者中使用更为频繁（39/82 = 48% 对比 138/848 = 16%，p<0.001）。需要分流管的患者RRR显著降低（0.95（0.41 - 1.53）对比1.0（0.54 - 1.9），p = 0.002），这仅适用于对侧ICA通畅的患者。对比RRR阈值（<0.7对比>1.3）或术前血压水平（<100 mmHg对比>120 mmHg）时，分流率无差异。直接分流或延迟分流患者的RRR无差异。RR3与RR2无显著差异。回归分析确定对侧ICA闭塞的存在是影响分流管插入的唯一独立参数。
局部麻醉下CEA期间全身血压的变化似乎对分流影响较小。诱导性高血压预防脑缺血的价值应重新探讨。
