Ostomy is a drainage channel in the abdomen through surgical operation due to digestive or urinary system diseases, commonly known as "artificial anus". The purpose of ostomy is to improve the quality of life. If the quality of life of patients is not improved after operation, the operation will be meaningless. The data confirmed that the increase in the incidence of colorectal cancer directly led to the increase in the number of stomas. There are about 100,000 emergency colostomy cases in the United States, 100,000 emergency colostomy cases in Britain and 100,000 new permanent colostomy cases in China every year. Physiological changes brought by ostomy: * Change of defecation or urination habits. * The normal outlet of feces and urine is displaced from the concealed perineum to the abdomen. * The new excretion function cannot be controlled at will. * Excretion after ostomy is irregular and uncontrolled. * Especially for ileostomy, intestinal fluid excretion is large, thin and irritating, which brings difficulties to nursing care of stoma.