Establishment of antegrade selective cerebral perfusion for a brain with old infarction during aortic arch operation

目的：我们试图研究pH值管理在顺行选择性脑灌注（ASCP）对大脑有或无陈旧性梗死犬model.Methods：脑梗死犬模型的影响，通过注射圆柱形硅栓子。脑梗死模型中，犬有明显的神经功能缺损，并存活4周或更长时间。在24只杂种犬中进行深低温与ASCP（完整组; alpha-stat：A组（n=6），pH-stat：B组（n=6），梗塞组; alpha-stat：C组（n=6），pH-stat：D组（n=6））。术中检测血清丙二醛（MDA）和谷氨酸浓度，并测定中枢传导时间（CCT）和体感诱发电位波幅。结果如下：术中C组在降温期28℃时SmvO_2显著低于其他各组（p<0.05），动、静脉乳酸差显著高于其他各组（p<0.05）。pH-stat组在降温至复温28℃期间动脉PaCO_2显著高于alpha-stat组，pH显著低于alpha-stat组（p<0.05）。其他术中参数未显示组间存在任何差异。C组血清MDA、谷氨酸浓度显著升高，CCT显著延长，波幅比显著降低，结论：主动脉弓手术中应用ASCP进行pH-稳态管理，对陈旧性脑梗死患者的脑保护效果更好。

Objective : We sought to examine the influence of pH management during antegrade selective cerebral perfusion (ASCP) on brains with or without old infarction in a canine model.Methods : A cerebral infarct canine model was created by means of injection of cylindrical silicon embolus. The dogs had obvious neurological deficits and survived for 4 weeks or more included in the cerebral infarct model. Deep hypothermia with ASCP was performed in 24 mongrel dogs (intact group ; alpha-stat : Group A (n=6), pH-stat : Group B (n=6), infarct group ; alpha-stat : Group C (n=6), pH-stat : Group D (n=6)). The serum concentration of malondialdehyde (MDA) and glutamate were measured, and central conduction time (CCT) and amplitude in somatosensory evoked potentials were assessed during operation. Results : During surgery, in the group C, SmvO_2 was significantly lower (p<0.05) and venous-arterial lactate difference was significant higher (p<0.05) than in the other groups at 28℃ in the cooling phase. The pH-stat group showed significantly higher arterial PaCO_2 and lower pH than those in the alpha-stat group during the period from the cooling 28℃ to the rewarming 28℃ (p<0.05). The other intraoperative parameters did not show any differences among the groups. In the group C, the serum concentration of MDA and glutamate significantly increased and CCT significantly prolonged, and in the group C and group D, the amplitude ratio decreased significantly.Conclusions : pH-stat management, during aortic arch operation with the aid of ASCP, may provide the more effective protection for the brain with old infarction.