The following signs often appear in critically ill elderly people: 1. loss of consciousness, the patient is mostly drowsy, drowsy or even comatose, unresponsive to pain and other stimuli, loss of orbital reflex, inability to communicate with the outside world, inability to speak, inability to actively eat, incontinence, convulsions, etc. 2. pupillary changes, comatose elderly people may have unequal pupils or fixed dilated pupils on both sides, no eye movement, 3. 3.Tetraplegia, hypotonia and loss of physiological reflexes. 4.Changes in vital signs, the dying elderly may show changes in vital signs, including high fever or no increase in body temperature, gradual slowing of heart rate, gradual weakening of heartbeat, weak respiration, open-mouth breathing, respiratory rate less than 20 times/minute, accompanied by pale skin and mucous membranes, cold extremities, oliguria, etc. Symptoms of shock, blood pressure is often below 90/60 mmHg, and carotid artery pulsation is weak or absent. If these symptoms occur, the elderly person will die within a few minutes to a few hours.