There is a patient with axillary odor who is almost 6 months postoperative and still has a wound that has not healed, with a white fluid that can be squeezed out from under the trabecular surface and a strange smell. This patient actually developed this condition soon after surgery, but due to her busy schedule, she did not come to the hospital in time to communicate with her surgeon. Post-operative infection under the flap is a very difficult problem after axillary odor surgery. However, since the sweating system in the axilla no longer exists, in the short term, if there is bacterial infection under the flap, it is not easy to come out of the blocked follicle hole, and the external sterilization drugs naturally cannot penetrate into it, which is more likely to happen in patients with blood and fluid accumulation under the flap after surgery. Because the relatively closed space under the skin becomes a breeding ground for bacteria, over time, the fluid will develop into pus, and if there is residual sweat gland secretion at the same time, it will form a thick, milky white fluid with a strange odor. Then why does it cause subcutaneous fluid accumulation? One of the most important factors is the uneven pressure of the postoperative wound dressing, or the patient’s upper extremity activity that causes the postoperative axillary filling to shift and fall off, thus losing its effect of pressure. Therefore, meticulous pressure dressing is very important. However, if the dressing is too tight, it will lead to local ischemic necrosis due to excessive pressure on the flap, or even dotted or flaky bruises under the surrounding normal skin, and the patient will also experience pain and discomfort. At present, the duration of pressure bandaging is between 3-5 days, and patients should follow the doctor’s instructions to go to the hospital to check the survival of the flap and whether there is fluid accumulation. Intraoperative bleeding, poor hemostasis, incomplete removal or regeneration of sweat glands are also among the many causes of subcutaneous fluid accumulation. Clinically, I have also seen patients who were afraid to bathe or touch water for a long time after surgery, resulting in serious fluid and pus accumulation due to local bacterial infection. Another reason why a significant number of patients’ wounds do not heal is due to flap necrosis and local skin defects. Sometimes the area of necrosis is quite large, up to about 4 cm in diameter, and the appearance of a red, blood-red blur is very frightening. This is a complication that causes considerable headache for many surgeons after recurrence and is one of the causes of postoperative burden for patients in the short term, ranking second in the severity of complications.