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，可导致猝死或严重心肺功能损害。最近使用经食管超声心动图（TEE）的研究已经清楚地检测到可变的回声事件，例如90-98%的THA患者中流入右心房（RA）的血流中的暴风雪和/或大栓子。回声大栓子的大小相当大，足以插入肺叶或肺段血管。因此，TEE检测到的回声大栓子可能导致THA术中和术后PE的急性发展。TEE显示，在使用骨水泥的THA期间，回声大栓塞现象的发生率很高。然而，目前尚不清楚术中宏观回声栓子是否是THA患者手术当天（POD 0）肺栓塞（PE）的关键原因。方法.术中TEE图像用磁带连续记录， ...更多信息 在整个手术过程中评价了心脏事件。本研究纳入了42例手术过程中宏观回声栓子检测阳性的患者。术后PE的发生通过多探测器计算机断层扫描（MDCT）或灌注肺动脉造影（PLS）证实。MDCT组22例，于术后第0天行MDCT增强扫描。结果MDCT组患者在POD 0时均未出现PE。在整个研究过程中，血流动力学和呼吸参数（包括心率、动脉血压、潮气末二氧化碳和外周动脉血氧饱和度）在组间无差异。两组术中TEE结果的各项分级评分，包括右心房内回声颗粒的数量、回声产生的最长时间、最大回声颗粒的直径和平均密度，均无差异。结论在POD 0行骨水泥全髋关节置换术患者中，术中回声强的巨栓子不是导致肺大血管阻塞的直接原因。继发血栓形成可能导致POD 1时肺血管阻塞。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