Ibrahim M F, Venn G E, Young C P, Chambers D J
Cardiac Surgical Research and Cardiothoracic Surgery, The Rayne Institute, St. Thomas' Hospital, London, UK.
Eur J Cardiothorac Surg. 1999 Jan;15(1):75-83. doi: 10.1016/s1010-7940(98)00287-5.
Myocardial protection with blood cardioplegia during cardiac surgery is increasingly preferred, but few studies have compared the protective effects of crystalloid cardioplegia to the same solution with blood as the only variable. This clinical study compared the protective effects of crystalloid or blood-based St. Thomas' Hospital cardioplegic solution No. 1.
Fifty higher risk patients undergoing elective coronary artery bypass surgery, with an ejection fraction less than 40%, were randomly allocated to receive cold (4 degrees C) intermittent crystalloid St. Thomas' No. 1 cardioplegia (n = 25), or a similar blood-based solution (n = 25) with a haematocrit of 10-12%. We determined (1) peri-operative and post-operative arrhythmias, (2) left and right ventricular function (24 h) using the thermodilution technique, (3) left ventricular high-energy phosphate content sampled before ischaemia, the end of ischaemia and the end of bypass.
Pre-operative haemodynamic data, aortic cross-clamp and bypass times were similar in both groups of patients; there was no mortality. At the end of ischaemia there were no differences in ATP content between groups but creatine phosphate was maintained at a significantly (P < 0.007) higher level in the blood-based St. Thomas' cardioplegia group than the crystalloid St. Thomas' cardioplegia group (20+/-2 (SE) vs. 13+/-1 micromol/g dry wt, respectively). Return to spontaneous sinus rhythm was significantly (P = 0.002) increased in the blood-based St. Thomas' cardioplegia group (96%) compared to the crystalloid St. Thomas' cardioplegia group (60%). Early post-operative ventricular dysfunction occurred in both groups, but normal LV function (stroke work index) recovered significantly (P = 0.043) more rapidly (by 2 h) in the blood-based St. Thomas' cardioplegia group of patients.
In a higher risk (EF < 40%) group of patients undergoing elective cardiac surgery, addition of blood to an established crystalloid cardioplegic solution significantly enhanced myocardial protection by reducing arrhythmias, improving rate of recovery of function and maintaining myocardial high-energy phosphate content during ischaemia.
心脏手术期间采用含血心脏停搏液进行心肌保护越来越受到青睐，但很少有研究将晶体心脏停搏液与唯一变量为添加血液的相同溶液的保护效果进行比较。这项临床研究比较了晶体或含血的圣托马斯医院1号心脏停搏液的保护效果。
50例接受择期冠状动脉搭桥手术、射血分数低于40%的高危患者被随机分配接受冷（4℃）间歇性晶体圣托马斯1号心脏停搏液（n = 25），或类似的含血溶液（n = 25），血细胞比容为10 - 12%。我们测定了：（1）围手术期和术后心律失常情况；（2）使用热稀释技术测定左、右心室功能（术后24小时）；（3）在缺血前、缺血结束时和体外循环结束时采集左心室高能磷酸含量。
两组患者术前血流动力学数据、主动脉阻断和体外循环时间相似；无死亡病例。缺血结束时，两组间ATP含量无差异，但含血的圣托马斯心脏停搏液组磷酸肌酸水平显著（P < 0.007）高于晶体圣托马斯心脏停搏液组（分别为20±2（标准误）与13±1微摩尔/克干重）。与晶体圣托马斯心脏停搏液组（60%）相比，含血的圣托马斯心脏停搏液组恢复窦性心律的比例显著（P = 0.002）增加（96%）。两组术后早期均出现心室功能障碍，但含血的圣托马斯心脏停搏液组患者左心室功能（每搏功指数）恢复正常的速度显著（P = 0.043）更快（提前2小时）。
在接受择期心脏手术的高危（射血分数<40%）患者组中，在既定的晶体心脏停搏液中添加血液可通过减少心律失常、提高功能恢复率以及在缺血期间维持心肌高能磷酸含量，显著增强心肌保护作用。
