Whenever surgery is mentioned, few people are not afraid, one reason being the unbearable pain after surgery. It is found that about 95% of the patients undergoing surgery are worried, anxious and uneasy because of the fear of pain, and some of them have panic attacks and increased blood pressure. Postoperative pain makes them afraid to breathe hard, cough and turn their position, and secretions are not easily discharged, causing pulmonary atelectasis and lung infection. For a long time, people think that postoperative pain is inevitable, and the traditional analgesic method is only the injection of morphine, dulcolax and other analgesic drugs, but there are disadvantages such as short analgesic time and the need for repeated medication. In recent years, a new technology has emerged in clinical pain treatment – drug pump technology, and the drug administration scheme is shifted to be given by patients themselves, i.e. patients use drug pumps to “self-controlled analgesia” (referred to as PCA technology). The principle of PCA technology is to use microcomputer control to set the technical parameters on the analgesia machine according to the patient’s condition, and the analgesia is administered by the patient in a safe and effective range. When the patient feels a little pain, he only needs to press the button of the analgesic pump, and the analgesic medicine will be input into the body slowly through the catheter, the amount is small and even, so that the drug can maintain a stable blood concentration in the body. the number of presses and drug dosage of PCA can be self-regulated by the patient, so that the analgesic medicine can be “supplied on demand”. It can achieve the best effect with the smallest dose and the smallest side effects, avoiding the traditional method of large fluctuations in blood concentration and side effects. This is another manifestation of modern technology for the benefit of patients.