Now it is the peak time for the return journey of the Spring Festival transportation. The doctor reminded that it is easy to form blood clots after Yang Kang. You should pay attention to drinking more water and moving your lower limbs on the way when taking a long-distance bus or plane. Zhan Shaofeng, chief physician of the Department of Respiratory and Critical Care Medicine of the First Affiliated Hospital of Guangzhou University of Traditional Chinese Medicine, said that infection with COVID-19 would increase the risk of thrombosis, and this change in coagulation function might be related to inflammatory reaction, which would be more obvious in patients who developed into severe cases. Previously, it was reported that the increased risk of thrombus in patients with COVID-19 infection mainly occurred in the first 30 days after infection. However, some studies have found that it may take several months for the risk to completely fall back to the pre-infection level. In the process of long-distance travel, passengers' legs are limited in a narrow space, which is one of the risk factors leading to venous thrombosis, which is also known as "economy class syndrome". At present, the temperature is low everywhere. The cold will slow down blood circulation and increase the risk of thrombosis. Small thrombus can have great hidden danger. Zhan Shaofeng said that once the thrombus formed in the leg vein falls off, it may run to the lungs along the blood circulation, blocking the pulmonary artery, and then leading to life-threatening hypoxia. Zhan Shaofeng reminded that Yangkang people should not only take protective measures such as wearing masks, but also pay attention to the prevention of thrombosis during the return journey. Drink more water on the way to avoid too thick blood; Increase the frequency of getting off and getting up to move both lower limbs. When it is really impossible to move, you can repeatedly straighten the instep and hook up the toes to achieve the effect of constantly squeezing the leg muscles and promoting the blood circulation of the lower limbs. If the Yangkang person has formed thrombus before, he can take preventive drugs in advance and wear elastic socks under the guidance of the doctor. The last thing to remind is that the swelling and pain of one leg after taking a long-distance bus or plane may indicate that there may be venous thrombosis of the lower limb, and you should seek medical attention as soon as possible. In case of chest tightness, chest pain and suffocation, be alert to pulmonary embolism caused by thrombosis, and call 120 immediately. (Outlook New Era)