Baker J E, Olinger G N, Boerboom L E
Department of Cardiothoracic Surgery, Medical College of Wisconsin, Milwaukee.
Thorac Cardiovasc Surg. 1993 Oct;41(5):274-9. doi: 10.1055/s-2007-1013871.
We determined the influence of perfusate composition and reinfusion during ischemia upon myocardial protection in the immature rabbit heart. Isolated "working" hearts (n = 6 per group) from 7-10-day-old New Zealand White rabbits were perfused with Krebs bicarbonate buffer and function measured. Hearts were then arrested with 3 minutes cold (14 degrees C) perfusion with bicarbonate buffer (as hypothermia-alone group) or St. Thomas' II cardioplegic solution (as hypothermia-plus-cardioplegia group). Hearts were then subjected to hypothermic (14 degrees C) global ischemia for 2 or 6 hours, with and without multiple reinfusion of the coronary vasculature. Following 2 hours ischemia impaired recovery of aortic flow occurred after multiple reinfusion in comparison with a single infusion with the cardioplegic solution (64 +/- 3% versus 72 +/- 4%) but not with bicarbonate buffer (79 +/- 3% versus 83 +/- 4%). However after 6 hours ischemia impaired recovery of function occurred after multiple reinfusion in comparison with single infusion both with the cardioplegic solution (60 +/- 3% versus 68 +/- 3%) and with bicarbonate buffer (57 +/- 4% versus 75 +/- 5%). There were no differences in post-ischemic creatine kinase leakage or myocardial water content between groups. These results suggest (i) that reinfusion itself, regardless of the composition of the perfusate, caused decreased recovery of function after an extended period of ischemia, and (ii) protection of the ischemic immature heart with St. Thomas' II solution remains inadequate and requires improvement.
我们确定了缺血期间灌注液成分和再灌注对未成熟兔心脏心肌保护的影响。从7至10日龄的新西兰白兔获取离体“工作”心脏（每组n = 6），用 Krebs 碳酸氢盐缓冲液灌注并测量其功能。然后，心脏用碳酸氢盐缓冲液进行3分钟冷（14℃）灌注使其停跳（作为单纯低温组），或用圣托马斯II号心脏停搏液灌注使其停跳（作为低温加心脏停搏组）。接着，心脏在14℃下进行2或6小时的低温全心缺血，期间冠状动脉血管有或没有多次再灌注。缺血2小时后，与单次输注心脏停搏液相比，多次再灌注后主动脉血流恢复受损（64±3%对72±4%），但与碳酸氢盐缓冲液相比无此现象（79±3%对83±4%）。然而，缺血6小时后，与单次输注心脏停搏液（60±3%对68±3%）和碳酸氢盐缓冲液（57±4%对75±5%）相比，多次再灌注后功能恢复受损。各组之间缺血后肌酸激酶泄漏或心肌含水量无差异。这些结果表明：（i）无论灌注液成分如何，再灌注本身会导致长时间缺血后功能恢复下降；（ii）用圣托马斯II号溶液对缺血未成熟心脏的保护仍然不足，需要改进。
