Goor D A, Mohr R, Lavee J
J Thorac Cardiovasc Surg. 1982 Aug;84(2):237-42.
The effectiveness of deep systemic hypothermia (20 degrees C) in myocardial protection during aortic cross-clamping was elevated. Seventy-one consecutive patients undergoing coronary artery bypass grafting were divided into two groups. In group A (32 patients) systemic temperature was reduced to an average of 26.8 degrees C (range 24 degrees to 28 degrees C) and the amount of cardioplegic solution infused totalled 1,000 to 1,200 cc. In Group B (39 patients) systemic temperature was reduced to an average of 20.8 degrees C (17 degrees to 23 degrees C) and the total amount of cardioplegic solution infused was 100 to 300 cc. The mean number of coronary (distal) anastomoses per patient was 4.46 in Group A and 4.51 in Group B. There were no surgical deaths, perioperative infarcts, or neurologic damage in either group. Postoperative catecholamine dependence was used as an indicator for inadequate myocardial protection. Catecholamine support was required by 18 patients (56.25%) in Group A and two patients (5.13%) in Group B (p less than 0.0001). Patients of both groups who received five or six coronary anastomoses, whose aortic cross-clamp time was 60 minutes or more, and whose preoperative left ventricular ejection fractions were above 50% were compared: Ten of the 11 (91%) in Group A required catecholamine support as opposed to none of the 12 in Group B (p less than 0.0001). No significant difference in the incidence of catecholamine requirement was found between patients of both groups whose aortic cross-clamp time was less than 60 minutes (2/13 patients in Group A and 2/21 patients in Group B), regardless of their preoperative left ventricular ejection fraction. We conclude that when aortic cross-clamp time exceeds 60 minutes, that is, when multiple distal anastomoses are performed, deep systemic hypothermia is a simple and effective method for myocardial preservation.
在主动脉交叉钳夹期间，深度全身低温（20摄氏度）对心肌的保护效果得到了提升。71例连续接受冠状动脉旁路移植术的患者被分为两组。A组（32例患者）全身温度平均降至26.8摄氏度（范围为24摄氏度至28摄氏度），注入的心脏停搏液总量为1000至1200毫升。B组（39例患者）全身温度平均降至20.8摄氏度（17摄氏度至23摄氏度），注入的心脏停搏液总量为100至300毫升。A组患者平均每人冠状动脉（远端）吻合口数量为4.46个，B组为4.51个。两组均无手术死亡、围手术期梗死或神经损伤情况。术后儿茶酚胺依赖被用作心肌保护不足的指标。A组有18例患者（56.25%）需要儿茶酚胺支持，B组有2例患者（5.13%）需要（p<0.0001）。对两组中接受五六个冠状动脉吻合口、主动脉交叉钳夹时间为60分钟或更长时间且术前左心室射血分数高于50%的患者进行比较：A组11例中有10例（91%）需要儿茶酚胺支持，而B组12例中无一例需要（p<0.0001）。两组中主动脉交叉钳夹时间少于60分钟的患者（A组13例中的2例和B组21例中的2例），无论其术前左心室射血分数如何，儿茶酚胺需求发生率无显著差异。我们得出结论，当主动脉交叉钳夹时间超过60分钟，即进行多个远端吻合时，深度全身低温是一种简单有效的心肌保护方法。
