Prolonged bed rest may lead to lower extremity venous thrombosis, acute cerebral infarction, etc. These thrombosis may be fatal. 1. Lower extremity venous thrombosis: if the patient is bedridden for a long time, it will lead to slow blood flow and form double lower extremity venous thrombosis. At the onset of symptoms such as swelling of the limbs, if not treated in a timely manner, the thrombus can fall off and block the pulmonary artery with the blood circulation, resulting in pulmonary embolism, the patient may experience respiratory distress and life-threatening. 2. Acute cerebral infarction: long-term bedridden is a high-risk factor of cerebrovascular disease, there may be acute cerebral infarction, if there is a large area of cerebral infarction, it can lead to increased cranial pressure, and even the formation of cerebral hernia and death. Long-term bedridden patients should strengthen the nursing care, follow the doctor’s instructions and timely use of medication, etc..