Is the burn wound really healed once it dries and forms a scab?

This is the 4684th article of Da Yi Xiao Hu

The healing of burn wounds is a complex process of regeneration and repair of various tissues in the human body after burns, accompanied by granulation tissue proliferation, angiogenesis, scar tissue formation, etc. Due to differences in the cause of the injury, the degree of burns, the treatment methods received by the wounds, and the patient's general condition, the appearance of the burn wounds of patients is also different.

In the eyes of ordinary people, burn wounds are considered healed when they are dry and scabbed. In fact, there are actually two situations in which burn wounds are dry and scabbed. One is that the wound has really healed, and the defect formed after the necrotic tissue of the burn wound falls off has been covered by new epithelial cells or fibrous tissue. In this case, we usually regard it as wound healing, which usually occurs in common superficial burns and scalds and superficial skin abrasions that we often see.

Another situation is that the exudate, blood and necrotic tissue of the wound dry and form a hard scab on the surface of the wound. Although the wound looks dry and has no water, it is not completely healed. There may be two changes in this kind of wound. One is that there is no infection, and the dry scab forms a protective barrier. The wound heals slowly under the scab. After the wound is finally healed, the dry scab falls off naturally. In this case, although the wound can heal, the speed of healing under the scab is generally much slower than that in a moist environment without scab formation, and there is a high probability of scar hyperplasia in the later stage. Another possibility is that the dry scab becomes infected and dissolves, and the wound gradually heals after the scab falls off. Once infected, the wound is likely to deepen, and severe cases may even require surgical treatment. This is usually seen in deep burns, bedsores, etc. For example, burns from hot water bottles and heat pads are common in clinical practice in autumn and winter. In the early stages, they usually manifest as small blister wounds. As the blisters rupture, the wound begins to scab over. At this time, patients often feel that the surface of the wound is dry and scabbed, and they don't care much. However, when the scab comes into contact with water, it becomes wet and soft, which provides favorable conditions for bacterial growth. Inflammatory reactions such as redness, swelling, and pain begin to appear around the wound, and only then does it attract attention.

Therefore, the drying of a burn wound does not necessarily mean that the wound has healed. Whether the wound has healed still needs to be judged by a professional burn doctor.

Author: Song Guorong, Burns Department, Shanghai Electric Power Hospital

Reviewer: Guo Yufeng