Thermal burns are a severe form of trauma which cause significant soft tissue injury as well as metabolic changes affecting fluid balance. While most burns are minor and do not require hospitalization, extensive burns are a life-threatening emergency. Extremes of age influence the outcome; the very young and the very old do not tolerate burns well. The circumstances of a burn injury will indicate possible associated injuries.

Begin treatment with airway management and fluid resuscitation. The volume of normal saline or Ringer’s lactate required is estimated using the Rule of 9’s. Complete the primary and secondary survey and then begin wound treatment (see the Annex: Primary Trauma Care Manual).

Thermal energy causes coagulation and death of varying levels to the epidermis, dermis and subcutaneous tissues. Viable tissue on the periphery of the burn may be salvaged if tissue perfusion is maintained and infection is controlled.

Classification of depth of burn

The depth of a burn depends upon the temperature of the heat source and the duration of its application. Burns can be classified as superficial, dermal or full-thickness. Flash burns are generally superficial; carbon deposits from smoke may give such burns a charred appearance. House fires, burning clothing, burning cooking oil, hot water scalds and chemicals usually produce mixed full-thickness and dermal burns; whereas molten metal, electric current, and hot-press machines normally cause full-thickness burns.

First degree (superficial) burns

The tissue damage is restricted to the epidermis and upper dermis. Nerve endings in the dermis become hypersensitive and the burn surface is painful. Blister formation is common. If the burn remains free from contamination, healing without scarring takes place in 7–10 days.

Second degree (dermal) burns

The lowest layer of the epidermis, the germinal layer, derives support and nourishment from the dermis. Portions of the germinal layer remain viable within the dermis and are able to re-epithelialize the wound. A deeper burn penetrates into the dermis and fewer epidermal elements survive. The amount of residual scarring correlates with the density of surviving epidermal elements.

Healing of deep dermal burns may take longer than 21 days and usually occurs with such severe scarring that skin grafting is recommended. Because the vessels and nerve endings of the dermis are damaged, dermal burns appear paler and are less painful than superficial burns.

Third degree (full-thickness) burns

Full-thickness burns destroy all epidermal and dermal structures. The coagulated protein gives the burn a white appearance, and neither circulation nor sensation are present. After separation of the dead eschar, healing proceeds very slowly from the wound edges. Skin grafting is always required, unless the area is very small. Severe scarring is inevitable.

Mixed depth
Burns are frequently of mixed depth. Estimate the average depth by the appearance and the presence of sensation. Base resuscitation on the total of second and third degree burns and local treatment on the burn thickness at any specific site.

Wound care

First aid

If the patient arrives at the health facility without first aid having been given, drench the burn thoroughly with cool water to prevent further damage and remove all burned clothing. If the burn area is limited, immerse the site in cold water for 30 minutes to reduce pain and oedema and to minimize tissue damage.

If the area of the burn is large, after it has been doused with cool water, apply clean wraps about the burned area (or the whole patient) to prevent systemic heat loss and hypothermia. Hypothermia is a particular risk in young children. The first 6 hours following injury are critical; transport the patient with severe burns to a hospital as soon as possible.

Initial treatment

Initially, burns are sterile. Focus the treatment on speedy healing and prevention of infection. In all cases, administer tetanus prophylaxis (see pages 4–10 to 4–12).

Except in very small burns, debride all bullae. Excise adherent necrotic (dead) tissue initially and debride all necrotic tissue over the first several days. After debridement, gently cleanse the burn with 0.25% (2.5 g/litre) chlorhexidine solution, 0.1% (1 g/litre) cetrimide solution, or another mild water-based antiseptic. Do not use alcohol-based solutions. Gentle scrubbing will remove the loose necrotic tissue. Apply a thin layer of antibiotic cream (silver sulfadiazine). Dress the burn with petroleum gauze and dry gauze thick enough to prevent seepage to the outer layers.

Daily treatment

Change the dressing on the burn daily (twice daily if possible) or as often as necessary to prevent seepage through the dressing. On each dressing change, remove any loose tissue. Inspect the wounds for discoloration or haemorrhage which indicate developing infection. Fever is not a useful sign as it may persist until the burn wound is closed. Cellulitis in the surrounding tissue is a better indicator of infection. Give systemic antibiotics in cases of haemolytic streptococcal wound infection or septicaemia. Pseudomonas aeruginosa infection often results in septicaemia and death. Treat with systemic aminoglycosides.

Administer topical antibiotic chemotherapy daily. Silver nitrate (0.5% aqueous) is the cheapest, is applied with occlusive dressings but does not penetrate eschar. It depletes electrolytes and stains the local environment. Use silver sulfadiazine (1% miscible ointment) with a single layer dressing. It has limited eschar penetration and may cause neutropenia. Mafenide acetate (11% in a miscible ointment) is used without dressings. It penetrates eschar but causes acidosis. Alternating these agents is an appropriate strategy.

Treat burned hands with special care to preserve function. Cover the hands with silver sulfadiazine and place them in loose polythene gloves or bags secured at the wrist with a crepe bandage. Elevate the hands for the first 48 hours, and then start the patient on hand exercises. At least once a day, remove the gloves, bathe the hands, inspect the burn and then reapply silver sulfadiazine and the gloves. If skin grafting is necessary, consider treatment by a specialist after healthy granulation tissue appears.

Healing phase

The depth of the burn and the surface involved influence the duration of the healing phase. Without infection, superficial burns heal rapidly. Apply split thickness skin grafts to full-thickness burns after wound excision or the appearance of healthy granulation tissue.

Plan to provide long term care to the patient. Burn scars undergo maturation; at first being red, raised and uncomfortable. They frequently become hypertrophic and form keloids. They flatten, soften and fade with time, but the process is unpredictable and can take up to two years.

In children, the scars cannot expand to keep pace with the growth of the child and may lead to contractures. Arrange for early surgical release of contractures before they interfere with growth.

Burn scars on the face lead to cosmetic deformity, ectropion and contractures about the lips. Ectropion can lead to exposure keratitis and blindness and lip deformity restricts eating and mouth care. Consider specialized care for these patients as skin grafting is often not sufficient to correct facial deformity.

Nutrition

The patient’s energy and protein requirements will be extremely high due to the catabolism of trauma, heat loss, infection and demands of tissue regeneration. If necessary, feed the patient through a nasogastric tube to ensure an adequate energy intake (up to 6000 kcal a day). Anaemia and malnutrition prevent burn wound healing and result in failure of skin grafts. Eggs and peanut oil are good, locally available supplements.