Geriatric diseases refer to diseases that affect people over 60 years old and are not unique to the elderly. 1, multi-morbidity refers to the same elderly often have more than two diseases at the same time. For example, many elderly people suffer from hypertension, atherosclerosis, chronic bronchitis, emphysema or renal impairment, which makes the symptoms atypical and causes difficulties in diagnosis and differential diagnosis, and requires vigilance. 2.Symptoms and signs are atypical The senility of the elderly is reduced, coupled with the fact that they often suffer from a variety of complications, which makes the symptoms and signs atypical and easy to miss or misdiagnose, for example, pneumonia in the elderly is often asymptomatic; or only shows poor appetite, general weakness, dehydration; or sudden impairment of consciousness without respiratory symptoms. 3. Rapid onset and short duration of illness. Due to the low organ reserve function of the elderly, the condition deteriorates rapidly once the stress occurs. 4.Many complications Easy to have consciousness disorder, which is related to cerebral vascular sclerosis in the elderly. Blood pressure changes, infections, toxic blood and dielectric disorders are related. Easy to cause water-electrolytic disorders The elderly brain is in a state of atrophy, the sensitivity of the thirst center is reduced, and not much water is drunk, thus minor causes can cause water-electric balance disorders, attention should be paid to the tongue, skin elasticity and urine volume. Complications prone to sequelae Such as long-term bed rest can cause pneumonic pneumonia, constipation, muscle atrophy, postural hypotension, limb contracture, osteoporosis, bedsores, etc. 5.Multiple types of medications Easy to have adverse drug reactions. 6.Easy to occur multi-organ failure.