Boivie Patrik, Hansson Magnus, Engström Karl Gunnar
Department of Surgical and Perioperative Science, Umeå University Hospital, Umeå, Sweden.
J Thorac Cardiovasc Surg. 2003 Jun;125(6):1451-60. doi: 10.1016/s0022-5223(03)00027-8.
Atherosclerosis of the ascending aorta and use of aortic crossclamping are risk factors for neurologic injury during cardiac surgery.
Repeated aortic manipulation is part of the surgical approach to most cardiac operations. The aim of this study was to assess the amount and size of particulate matter that is dislodged from the aortic wall as a function of repeated aortic crossclamping.
In 10 subjects undergoing autopsy the aorta was dissected and mounted in a perfusion model. The ascending aorta was crossclamped and washed out 10 times, with the perfusate collected in aliquots (1 to 10). The aliquots were examined by computerized image processing, both macroscopically and under the microscope for calcified and cellular material.
Aortic crossclamping produced substantial output of particulate matter. After repeated aortic crossclamping the number of particles decreased (P =.012) and approached the baseline for aliquots 6 to 10. The average particle diameter was 0.63 +/- 0.03 mm, with a maximum of 4.74 mm. Similar variability in particle outputs were recorded microscopically, with findings of both calcified and cellular material. Nine of 10 aortas had calcifications seen during simple visual inspection.
The washouts of dislodge material at aortic crossclamping had embolic potential. During the initial aortic crossclamping procedures the amount of particles was substantial, both macroscopically and microscopically. On the microscopic scale noncalcified cellular debris represents a significant pool of embolic material. Repeated aortic crossclamping reduced the amount of particles. These findings question surgical techniques associated with repeated aortic crossclamping.
升主动脉粥样硬化和主动脉交叉钳夹的使用是心脏手术期间神经损伤的危险因素。
重复的主动脉操作是大多数心脏手术手术方法的一部分。本研究的目的是评估随着主动脉交叉钳夹次数增加从主动脉壁上脱落的颗粒物质的数量和大小。
在10名接受尸检的受试者中，解剖主动脉并将其安装在灌注模型中。升主动脉被交叉钳夹并冲洗10次，灌注液收集成分份（1至10）。通过计算机图像处理对这些份样进行宏观和显微镜下检查，以检测钙化物质和细胞物质。
主动脉交叉钳夹产生了大量的颗粒物质输出。重复主动脉交叉钳夹后，颗粒数量减少（P = 0.012），并接近第6至10份样的基线水平。平均颗粒直径为0.63±0.03毫米，最大为4.74毫米。在显微镜下记录到类似的颗粒输出变异性，同时发现了钙化物质和细胞物质。在10个主动脉中，有9个在简单目视检查时可见钙化。
主动脉交叉钳夹时冲洗出的物质具有栓塞潜力。在最初的主动脉交叉钳夹过程中，无论在宏观还是微观层面，颗粒数量都很多。在微观层面，未钙化的细胞碎片是大量栓塞物质的来源。重复主动脉交叉钳夹减少了颗粒数量。这些发现对与重复主动脉交叉钳夹相关的手术技术提出了质疑。
