Experimental and Clinical Study of Selective Cerebral Perfusion under Profound Hypothermia

我们调查了以下三项关于体外循环期间脑保护的研究。31P磁共振逆行脑灌注脑保护作用的实验研究通过在体磷-31磁共振波谱(31-P MRS)测定脑组织中三磷酸腺苷(ATP)、磷酸肌酸(PCr)和细胞内pH值(Phi)，评价脑逆行灌注(RCP)过程中的脑代谢状态，并与正常脑灌注(NCP)和停循环(CA)进行比较。CA组出现严重的细胞内酸中毒和高能磷耗竭。与CA组相比，RCP组大鼠肺组织中的ATP没有耗竭，而PCr和Phi恢复得更快。本研究表明，RCP延长了CA2的安全持续时间。新的AMPA受体拮抗剂YM90K在仔猪中低温停循环期间具有潜在的脑保护作用。我们研究了新的AMPA受体拮抗剂YM90K[6…More-(1H-咪唑-1-基)-7-硝基-2，3(1H，4H)-喹恶烷二酮盐酸盐]，具有中度低血压停搏的脑保护作用。YM90K处理组30℃停滞后，PCr和PHI恢复均好于未处理组。证实YM90K能改善中低温停搏期间脑组织的能量代谢和PHI。S-100蛋白。S-100蛋白是一种酸性钙结合蛋白，在神经胶质细胞和雪旺细胞中含量较高。血清S-100蛋白升高提示神经元损伤。对体外循环心脏手术患者的S-100蛋白水平进行了检测。无脑并发症者体外循环后5~10小时S-100恢复至术前水平，而卒中患者术后24小时仍维持在较高水平。我们认为CPB期间和术后的S-100蛋白可以作为早期发现脑损伤的标志物之一。较少

We investigated the below three studies for cerebral protection during cardiopulmonary bypass.1. Experimental study of brain protection during retrograde cerebral perfusion using 31-P MRSWe evaluated metabolic state of the brain during retrograde cerebral perfusion (RCP), and compared it with normograde cerebral perfusion (NCP) and circuratory arrest (CA) by measuring the concentration of adenosine triphosphate (ATP), phosphocreatine (PCr), and intracellular pH (pHi) using in vivo phosphorous-31 magnetic resonance spectoscopy (31-P MRS). In the CA group, severe intracellular acidosis and depletion of high-energy phosphorous occured. The RCP group resulted in no depletion of ATP and faster recovery of Pcr and pHi than CA group. This study indicates that RCP prolongs safe duration of CA.2. A novel AMPA receptor antagonist, YM90K, has potential of brain protection during moderately hypothermic circulatory arrest on piglets.We investigated whether a novel AMPA receptor antagonist, YM90K [6 … More -(1H-imidazol-1-yl)-7-nitro-2, 3(1H, 4H)-quinoxalinedione hydrochioride], has potential for cerebral protection with moderately hypoyhermic circuratory arrest. In YM90K-treated 30℃ arrest group, Pcr and pHi recovered better than untreated group. It was conformed that administration of YM90K improved energy metabolism and pHi in cerebral tissue during moderately hypothermic circuratory arrest.3. S-100 protein during cardiopulmonary bypass.S-100 protein is an acidic, calcium binding protein found in high concentration in glial and Schwann cells. The elevation of S-100 protein in serum indicates neuronal damage. We measured S-100 protein level in patients who underwent cardiac surgery with cardiopulmonary bypass (CPB). In patients with no cerebral complications, S-100 concen-tration at 5-10 hours after CPB retuned to the level before CPB.However in whom with stroke, the S-100 level remained high 24 hours after. We thought S-100 protein during and after CPB could be one of the markers for early detection of cerebral injury. Less