There are many causes of lower limb edema after surgery that need to be treated differently. If the edema appears only in the limbs where the saphenous vein is extracted, especially in the ankle and calf areas, it is due to the fact that the venous return is affected to some extent after the veins of the lower limbs are removed, and the edema will be aggravated after standing for a long time and will be reduced or disappeared after bed rest. It is recommended that such patients wear special elastic stockings when moving down to the ground and elevate the lower limbs when resting in bed, which can promote venous return and reduce lower limb edema. The edema will gradually disappear with the establishment of lateral branch circulation in the lower extremities. If edema is present in both lower legs, it may be due to heart failure. If it is also accompanied by inability to lie down at night or wake up from sleep, it is highly suggestive of possible heart failure. You should go to the hospital promptly to avoid delaying the condition.