Painless surgery means that the patient is pain-free during the procedure, but pain may be present after the patient returns to the hospital room after the surgery. Generally, painless surgeries include surgeries under general anesthesia, such as abdominal surgeries or surface surgeries, and of course, painless abortion surgeries. In the process of surgery, anesthesia drugs and analgesic drugs are mainly pushed into the vein, so that the patient can achieve the effect of painless during the whole operation. However, after returning to the hospital room, there may be pain in the abdomen or incision because of the wound or trauma inside the abdominal cavity. If the pain is mild, oral painkillers or intramuscular injections of painkillers can be used to treat the symptoms, but if the pain is more severe, opioid analgesics, such as pethidine or morphine, may also be used.