With the development of medical technology and the improvement of living standards, the proportion of elderly people continues to rise, and our country is gradually stepping into an aging society. Compared with younger patients, elderly patients are more likely to be accompanied by chronic diseases, such as hypertension, diabetes, chronic bronchitis, etc. Their cardiopulmonary function reserves are poorer, and it is more difficult for them to withstand the blow of surgery and postoperative complications. Therefore, they may receive more examinations and laboratory tests before and after surgery, and the only way for patients and their families to better cooperate with the completion of preoperative examinations and perioperative care is to truly understand the characteristics of the body functions of elderly patients.1. Cardiovascular aspectsThe leading cause of postoperative death in patients over 80 years old is myocardial infarction, and more than half of the postoperative complications or postoperative deaths are related to the cardiovascular system. One reason for this is that diseases of the cardiovascular system are very common in the elderly. Intimal hyperplasia of coronary vessels is significantly associated with age, while increasing age also affects the cardiac conduction system, and arrhythmias are a common postoperative (especially thoracic) complication. Continued reduction of cardiomyocytes in the right and left ventricles as well as compensatory volume increases will cause abnormalities in cardiac blood supply. Therefore, for most elderly people, preoperative echocardiography and electrocardiography may be routinely performed, mainly to assess the cardiac reserve function and to prevent cardiac insufficiency or failure during the perioperative period.2. Respiratory aspects Due to the effects of increasing age on the respiratory muscles, ventilatory function, and pulmonary vasculature, elderly patients are often accompanied by a decrease in respiratory reserve function. Decreased strength of the diaphragm, calcification of the intercostal cartilage, and atrophy of the intercostal muscles will cause a weakening of the respiratory strength, and the surface area of the lungs that can be used for gas exchange will be reduced by 15% in a 70-year-old patient. Also, the body’s ability to absorb oxygen decreases with age. In addition, the weakening of the nerve reflexes of the elderly will make the patients with poor respiratory function more susceptible to aspiration, which will further increase the risk of pulmonary atelectasis and postoperative lung infection in elderly patients, so it is very necessary to assess the lung function of the patients through the preoperative expiratory test, etc. 3, renal function of the human body after the age of 50 years old will be a reduction in the number of renal units, and by the time the patient reaches the age of 70 years old, more than half of the renal units will be lost. disappear. Therefore, compared with younger patients, elderly patients are more likely to have abnormal renal function, electrolyte disorders and acid-base imbalance. At the same time, the reserve function of renal filtration is also reduced in elderly patients, resulting in a weakened ability to concentrate urine, which makes them more susceptible to ischemia or nephrotoxic substances, which in turn causes renal failure. Therefore, clinically, during the perioperative period, doctors may pay great attention to the urine output of elderly patients to avoid renal impairment as much as possible.4. Gastrointestinal functionGastrointestinal peristalsis will gradually weaken with the increase of age and its coordination is also poorer than that of the young people, so it is more likely to cause swallowing difficulties and aspiration after the operation. In terms of nutrient absorption, the villi of the small intestine of patients over 60 years old are shortened, which in turn causes the surface area for nutrient absorption to be reduced. Therefore, the risk of malnutrition is very high in elderly patients with high metabolic status caused by tumor and surgery. In addition, after the age of 50, the function of the liver decreases, and the ability to synthesize nutrients and metabolize toxins decreases accordingly, making patients more susceptible to malnutrition and other problems after surgery. The advent of an aging society is unstoppable. Whether it is the patients themselves or their families, or the doctors or caregivers, the only way to better understand the risks of treatment and avoid them is to carefully understand the characteristics of the body functions of the elderly. We believe that with the continuous development of minimally invasive treatment methods and the spread of the concept of individualized comprehensive treatment, we will be able to bring more suitable treatment and care to more elderly people.