Interaction between the endothelium injury of pulmonary vessels and the activated platelets on the formation of post operative pulmonary embolism

肺栓塞(PE)是全髋关节置换术(THA)的常见并发症，可导致猝死或严重的心肺功能障碍。最近使用经食道超声心动图(TEE)的研究清楚地发现了不同的回声事件，如90-98%的THA患者流入右心房(RA)的血流中有暴风雪和/或巨大栓子。回声巨大的栓子相当大，足以插入叶或节段性肺血管。因此，TEE检测到的回声大栓子可能导致THA术中及术后PE的急性发展。TEE显示在骨水泥全髋关节置换术中回声大栓子现象的发生率很高。然而，术中大量回声栓子是否是THA患者手术当天(POD0)肺栓塞(PE)的关键原因尚不清楚。方法：研究方法。术中TEE图像用磁带和e-…连续记录术中TEE图像在整个手术过程中对更多的脉络膜事件进行了评估。本研究纳入42例手术中检出大片回声栓子阳性的患者。术后肺栓塞的发生通过多层螺旋CT(MDCT)或肺灌注核素扫描(PLS)证实。手术结束后对POD0行多层螺旋CT扫描(MDCT组，n=22)。结果。MDCT组无1例在POD0出现PE。血流动力学和呼吸参数，包括心率、动脉血压、呼气末二氧化碳和外周动脉血氧饱和度，在整个研究过程中没有组间差异。术中TEE所见右房回声颗粒数量、最长回声时间、最大回声颗粒直径及平均密度两组间差异无统计学意义。结论术中回声巨大栓子不是POD0骨水泥全髋关节置换术中大肺血管阻塞的直接原因。继发性血栓形成可能导致POD时肺血管闭塞。较少

Pulmonary embolism (PE) is a well known complication of total hip arthroplasty (THA), and can lead to sudden death or severe cardiopulmonary impairment. Recent studies using transesophageal echocardiography (TEE) have clearly detected variable echogenic events, such as snowstorm and/or macro emboli in the bloodstream flowing into the right atrium (RA) in 90-98% of THA patients. The size of echogenic macro emboli was considerably large enough to plug into the lobar or segmental pulmonary vessels. Therefore, echogenic macro emboli detected by TEE might cause the acute development of PE during and following the procedure of THA. TEE has revealed a high incidence of the occurrence of echogenic macro embolic phenomena during THA with bone cement. However, it is still unknown whether intraoperative macro echogenic emboli crucially cause the pulmonary embolism (PE) on the day of surgery (POD0) in the THA patients. Methods. Intraoperative TEE images were continuously recorded by tape and the e … More chogenic events were evaluated throughout surgery. Forty two patients with the positive detection of macro echogenic emboli during surgery were enrolled in this study. The occurrence of the postoperative PE was confirmed by multi-detector computed tomography (MDCT) or perfusion lung scintigraphy (PLS). MDCT with contrast medium was performed on POD0 after the termination of surgery (MDCT group, n=22). Results. None of the patients in MDCT group presented the existence of PE on POD0. Hemodynamics and respiratory parameters including heart rate, arterial blood pressure, end-tidal carbon dioxide and oxygen saturation of peripheral artery did not differ between groups throughout the study. Each grading score of intraoperative TEE findings including the amount of echogenic particles in right atrium, the longest time of echogenesis, and the diameter and mean density of the largest echogenic particles did not differ between two groups. Conclusion Intraoperative echogenic macro emboli were not direct source of the obstruction of large pulmonary vasculature in the patients undergoing THA with bone cement on POD0. The secondary thrombi formation might cause the obstructions of pulmonary vasculature on POD1. Less