Patients have the following main precautions when performing wound dressing changes: i. If the wound is aseptic, the wound dressing can be changed 2-3 days after surgery. Pay attention to aseptic operation when changing dressings to avoid causing wound contamination. Second, for patients with long incisions, it is necessary to extend the vascular forceps into the incision and squeeze the incision during dressing change to observe whether there is subcutaneous effusion, and patients with effusion can be filled with gauze for drainage. Third, infected wounds, each drug change should be thoroughly cleared of necrotic tissue within the wound, and patients with pus accumulation need to drain the pus cleanly. After the wound is cleaned, topical growth factors and myogenic powder can be applied to promote the growth of granulation tissue. Four, infected wounds with more exudate is recommended to change the dressing daily to make the wound heal faster.