58.15 The closed (occlusive dressing) method

At the moment of burning a burn is sterile. The aim of the closed method is to keep it so, as far as possible, by sealing it off from the environment with an effective dressing, before it has become seriously contaminated. The bigger the burn, the more difficult this is. To be effective the dressing which covers a burn must be about 2 cm thick as in A, Fig. 58-10, so that it absorbs the exudate and prevents it reaching the surface where it can become infected. Gauze is more absorbent than cotton wool, but is more expensive. In practice, asepsis is difficult to achieve, especially with larger burns, so you should put some local antiseptic agent on the burn (58.22). Some surgeons would say you must do this. The best local agents are silver sulphadiazine cream or 0.5% silver nitrate with 0.2% chlorhexidine.

The closed method: (1) Demands more and better nursing care than the exposure method. (2) Needs abundant dressings. (3) Is more dependant on a local antiseptic agent than the exposure method. (5) Can cause hyperpyrexia in large burns in hot environments.

Done well, the closed method can be wonderfully successful. When you remove a dressing from a partial thickness burn which you have left undisturbed for 10 days, you may find perfect new skin underneath. But this method can be very dangerous if you forget that: (1) Dressing a burn is a surgical procedure, which must be done aseptically. (2) The aim of the dressings is to contain exudates, and prevent organisms reaching the burn. This means that you must change them on the indications given below.

Done badly, this method is a disaster, and too easily converts a partial thickness burn into a full thickness one. Doing it badly includes: (1) Not applying enough dressings (sometimes only a thin layer of gauze). (2) Letting exudates soak through without changing them. (3) Not bringing the dressing well beyond the edges of the wound.

Unfortunately, the closed method, badly done, is in widespread use. As such, it is painful, messy, expensive, and hinders healing. There should be no compromise—either a burn should be left open with nothing on it at all, or it requires 2 cm of dressings. There is a strong body of opinion which considers that the closed method has no place whatever for inpatients in the hospitals for which we write. Under our circumstances it is only suitable for parts of the body where the necessary dressings will stay in place. In effect, this means the limbs. In practice, because of the cost of the dressings and the labour involved, you will only find the closed method suitable for superfical small burns on the extremities of outpatients. It becomes increasingly difficult with larger burns, and on the trunk.