美国每年有15万人死于肺栓塞,这个数字可能远比实际的发生率为低。近年已经明确肺栓塞的来源是下肢深静脉的栓子,因此设法降低下肢深静脉血栓的形成至为重要。为比较多种方法在预防上的作用,作者作了如下观察。将500名年龄>40岁、手术时间超过一小时的多 Every year in the United States, 150,000 people die of pulmonary embolism, a figure that is far lower than the actual rate. In recent years, it has been clear that the source of pulmonary embolism is the embolus of the deep veins of the lower extremities. Therefore, it is important to try to reduce the formation of deep vein thrombosis in the lower extremities. To compare the role of various methods in prevention, the authors make the following observations. Will be 500 years old> 40 years old, operation time more than one hour more