The clinical method of determining wound tissue necrosis is determined by observing the change in color of the wound tissue, and the degree of elasticity of the wound tissue. Normal wound tissue is red in color, elastic, and may bleed when touched with surgical instruments. Necrotic wound tissue has no blood flow at all or is extremely deprived of blood flow and shows a pale color and poor elasticity. Some of the necrotic wound tissues have residual bruising inside, and then the tissues show a greenish-purple color. The necrotic tissue inside the wound needs to be cleaned in time. If it is not cleaned in time, more necrotic tissue remains inside the wound, which will easily lead to wound inflammation.