Most elderly people will have swelling of the lower limbs or even the whole body before they die, mainly for the following reasons: 1. Most elderly people cannot eat before they die, resulting in anemia and hypoproteinemia, which can cause a decrease in plasma colloid osmotic pressure, causing the water in the blood vessels to leak out to the outside of the blood vessels, and this excess water will gather under the skin, and it tends to gather in the lower limbs, sacral tail and other depressed parts of the body. Therefore, the phenomenon of swollen feet will appear; 2, the dying elderly are confused and unable to move, and the blood circulation in the lower extremities is poor, which leads to reduced venous blood return to the lower extremities and the symptoms of swollen feet; 3, serious heart, liver and kidney diseases can also cause swollen lower extremities; 4, the dying elderly are bedridden for a long time, which can easily cause deep vein thrombosis in the lower extremities, which leads to swollen feet.