Therapeutic approaches
and other measures
01
Wound Healing
Wound healing after burns occurs – albeit with a significant delay – according to the usual pattern, i.e., through the sprouting of capillaries into the stasis zone, subsequent shedding of necrotic tissue and epithelialization starting from the edge of the burn wound or – in second-degree burns – starting from the remnants of the skin appendages, especially the excretory ducts, in which remnants of epidermal cells are still found. The correct assessment of the depth of the burn is crucial for treatment. Superficial second-degree burns (2a) usually heal spontaneously within 14 days. Apart from pigmentary changes, normal, resilient skin regenerates. After deeper damage (2b), spontaneous healing can only progress with a delay, and the skin conditions never return to normal (defective healing). The consequences are reduced resilience of the skin surface and sometimes grotesque scars. Therefore, deep second-degree burns (2b) are an indication for early surgical treatment, as only surgical interventions can largely prevent these complications. In third-degree burns, the skin and its appendages are dead. Spontaneous healing is no longer possible – except in small wounds – due to wound contraction and epithelialization from the edges. Surgical treatment is mandatory.
02
Wound Infection
Infections are the cause of well over half of all deaths resulting from burns. After one week, it can be assumed that every burn is infected. Microorganisms find ideal nutrients on the burn wound. The natural barrier is destroyed, the general immune system is significantly reduced, and blood flow is minimized. This lack of blood flow also prevents the bloodstream from transporting defense mechanisms. In general, both non-specific and specific defense mechanisms are severely impaired. The burn trauma also profoundly alters the patient's basal metabolic rate. As a result of fluid and nutrient loss, as well as the reparative processes, the basal metabolic rate is extremely elevated, which leads to the depletion of the body's own reserves within a short period of time. The increase in metabolic rate is higher after a severe burn than after any other injury. Of course, the pathophysiological processes can only be briefly addressed here. However, the above provides important starting points for therapy. The most important therapeutic measures are: *Avoidance of burn shock through appropriate fluid replacement, *Early necroptomy and autologous skin transplantation, *Optimization of patient nutrition, particularly through early enteral nutrition, *Prevention of septic complications, *Creation of optimal external treatment conditions for the patient.
03
Combustion type
The distinction between thermal and non-thermal burns made here is for the sake of simplicity. Thermal exposure (e.g., flame) can result in direct burns to the skin or secondary burns from burning clothing. Hot water or steam can cause scalding, while liquid metal or hot solids can cause contact burns. Non-thermal burns can result from chemical, electrical, or radiation exposure. Thermal burns: *Direct burns, e.g., open flame (explosion) *Indirect burns, e.g., from burning clothing *Scalding from hot water, steam *Contact burns, e.g., from liquid metal, hot solids Non-thermal burns: *Chemical acids, alkalis, chemical warfare agents, solvents, etc. *Household electrical appliances, low-voltage and high-voltage currents, radiation-induced *Toxic, e.g., Lyell's syndrome or streptococcal toxin
04
Burn Depth
Traditionally, the depth of a burn is divided into three degrees of severity. Within this classification, second-degree burns are further divided into superficial second-degree and deep second-degree burns. The clinical features of burn depth can be classified by inspection and by determining pain sensation. To confirm the diagnosis, samples taken from burned skin areas can be examined histologically. In epidermal, superficial burns, only erythema develops as a result of the trauma. Additional blistering (= fluid accumulation between the epidermis and the dermis) indicates a superficial second-degree burn. If the hyperemic redness of the base of the blister can be pressed away, this indicates patency of the corium capillaries. The initially largely normal skin elasticity changes only after hours as edema develops. There is pronounced pain and a strong tendency to bleed upon contact. The skin appendages are intact, and the hair is firmly attached. After an injury to deeper layers of the corium, blisters appear, some fully inflated, some torn by pressure, whose wound base appears increasingly whitish. The latter is the result of further damage to the capillary network and the denatured protein of the corium. Any redness at the base of the blister is difficult to push away. Hairs located superficially in the corium fall out, and pain sensation decreases. A third-degree burn affects all skin structures. Burns that also damage the muscles, possibly also the bones, or other deeper structures can be referred to as fourth-degree burns. One diagnostic aid is the pinprick test. Pain sensation decreases with increasing burn depth. Despite extensive clinical experience, errors in estimating burn depth cannot be ruled out. The depth of the burn is often classified as superficial on the day of the accident, but after three to five days it can turn out to be significantly deeper than originally assumed. It is therefore essential to check the diagnosis at regular intervals.
05
Burning extent
Various rules are provided in the literature for assessing the extent of a burn. A simple rule of thumb states that the patient's palm corresponds to approximately one percent of their body surface area. However, Wallace's rule of nine is more precise. Even more precise classifications can be made, among other things, using the guidelines of the professional associations (burn questionnaires). The guidelines of the Bavarian State Association of Industrial Accident Insurance Associations can be used as an indication of whether a patient needs to be admitted to a burn center. Accordingly, adult patients should be referred to a burn center if the following conditions apply: *Third-degree burns of the face, hands, feet, or burns at other, particularly complicated locations, including electrical burns, *Second-degree burns exceeding 20 percent of the body surface area, *Third-degree burns exceeding 10 percent of the body surface area. *In the presence of inhalation trauma, in any case – i.e. Regardless of the degree and extent of the external burn, immediate access to a burn center should be sought. These principles also apply to scalds and chemical burns.
06
Treatments at the scene of the accident
Treatment of the injured person begins within the first few minutes at the scene of the accident. Immediate cooling of the wounds not only relieves pain but also prevents the so-called "afterburn," which limits the further penetration of thermal damage into the deeper layers. In our latitudes, tap water can be used for cooling without concern. The faster this measure is carried out, the more pronounced the therapeutic effect; a desired side effect is significant pain relief. However, hypothermia of the patient must be avoided at all costs. The motto is: Cool, yes – but use common sense. First aid involves remaining calm and paying particular attention to potential rescue risks. This is especially true in electrical accidents, where the power source must first be disconnected before assisting the patient. First aid measures for burns: *Smother burning clothing with blankets, clothing, and by rolling the victim on the ground. *Remove the burn victim to fresh air – if necessary, call the fire department (phone 112). *Extinguish smoldering clothing with tap water, if possible, to cool the burns until the pain subsides. *In the case of extensive burns, ensure that the victim does not become hypothermic; immediately remove any clothing soaked in hot liquids. *Carefully remove any other burnt clothing. Do not tear off any stuck-on clothing, but leave it in place. *If necessary, call an emergency doctor. *Transport the victim. The burns are initially sterile. They should only be covered with a sterile dressing, e.g., with burn dressing packs or burn wipes. If necessary, clean towels or, for more extensive burns, bedsheets can be used to cover burned areas of the body or the entire body. In the case of chemical burns, the victim should be rinsed thoroughly with water. This applies especially to the eyes, which require special attention. Clothing that has come into contact with the chemicals must be removed. In any case, the use of ointments, powders, and household remedies such as flour or oil, etc., should be avoided.
07
First aid in the clinic
Due to its staffing, equipment, and space, combined with a plastic surgery department, the Burn Center offers all the prerequisites for optimal, injury-specific treatment. When a patient is admitted to our center, at least * a plastic surgeon, * an anesthesiologist, * a nurse from the burn center, * and a nurse from the anesthesiology department are available. Intensive care measures begin in a special admissions room. Depending on the specific situation, central venous catheters, possibly also a pulmonary catheter, intra-arterial catheters, transurethral, or suprapubic catheters are inserted. Intubation, which is predominantly nasal, is only performed in our center after careful evaluation of the indication. Please note again that we are very cautious about making the indication for intubation. At the slightest suspicion of inhalation trauma, a laryngobronchoscopy is performed to confirm the diagnosis and to obtain tracheal secretions for bacteriological testing. Further diagnostic procedures follow. Additional injuries to the skull, face, chest, abdominal cavity, or extremities, as well as fractures and dislocations, must be treated surgically through the burn wound. Circular burns that impede breathing or circulation require an incision of the burn eschar and, in some cases, opening of the fascia(s). The patient is cleaned in a special shower bath. During the cleaning process, the extent and location of the burns, such as the depth of the burns, are mapped, and a preliminary treatment plan is developed. After the cleansing bath and after completion of the necessary surgical and diagnostic procedures, the patient is transferred to a sterile bed and transferred to the patient room. In these isolated "intensive care units," the room temperature is between 25 and 32 degrees Celsius and the humidity is approximately 50 to 60%. Since the patient must be treated under aseptic conditions, in addition to the special work clothing and headgear customary in intensive care units, a face mask, sterile gowns, and sterile gloves are mandatory when working on the patient.
08
Surface Therapy
There are essentially two options for the surface treatment of burns: * Open treatment, * Closed treatment. With open treatment, the aim is to keep the burn as dry as possible and/or to further scab the surface using the tanning method. With closed treatment, the wound is covered with a gauze dressing after applying an antimicrobial ointment or ointment gauze. Another closed treatment option is, for example, moistening the dressing with 0.5% silver nitrate solution or other disinfectant solutions. Depending on the specific circumstances, all of these options are utilized in our department. However, the basic treatment is the application of sulfadiazine silver cream (Flammazine®). Dressings are changed once daily. Cleansing shower baths are administered every one to two days, or daily if necessary. The Flammazine® dressing offers effective protection against bacterial colonization. It provides a pleasant cooling effect and guarantees largely pain-free relief. In our opinion, this method has the particular advantage that no dry scab forms, thus ensuring early physiotherapy treatment is not hindered. The intensive care course during the first three to five days is characterized by massive edema and electrolyte imbalances. Electrolytes must be replaced, acid-base balance must be balanced, and massive protein losses must be replaced. Once these problems have been controlled, the course of the disease is complicated and delayed by increasing infection of the wound area. This can lead to the patient developing a state of protracted sepsis, the effects of which are often uncontrollable. Significant complications include pulmonary insufficiency and/or renal insufficiency with or without multi-organ failure. Unfortunately, transient renal insufficiency is not uncommon in severely burn victims. In this case, the failure of renal function must be replaced by hemodialysis or by continuous or mechanical hemofiltration (the procedure we practice).
09
Early Excession
Circulation usually stabilizes by the third to fifth day after the injury. We now begin surgically removing the scabs. For deep second-degree burns, tangential excision of the burned skin is the treatment of choice. For third-degree burns, complete excision down to well-perfused tissue layers is necessary, and if necessary, complete excision down to the muscle fascia or even deeper. Immediate coverage with autologous skin grafts is recommended. However, if the wound is unclear, the wound is initially covered with allografts or a synthetic skin substitute. If contaminated, antiseptic gauze dressings are applied. In this way, 10 to a maximum of 20% of the body surface is treated at two- to three-day intervals to prevent dangerous autolysis and widespread wound infection. Due to the patient's condition, this optimal treatment concept is often not possible for severe burns. However, if early wound closure is achieved without protracted secondary healing, the scar-related contractures in the neck and joints that were so frequently observed in the past can be largely prevented. Secondary scar revisions can thus usually be avoided. This active surgical approach has been shown to significantly shorten the patient's hospital stay. Permanent wound closure is only possible through self-healing or through skin grafting from uninjured areas of the body. Allograft skin does not heal, with the exception of parts of the dermis. For third-degree burns, the method of choice is the removal of a very thin layer of epidermis that still contains a sufficient number of viable cells. This split-thickness skin graft can then be applied to the appropriately prepared wound and secured. Since healthy skin areas are often not available in sufficient quantities, the harvested split-thickness skin is incised with a special device to create a grid. This allows the split-thickness skin to be expanded to cover a larger wound area. The graft is secured by adhesive, suture, or staple fixation. For the first few days, the transplanted wounds are protected with an ointment gauze with or without an antiseptic component. Afterward, open treatment should be attempted as quickly as possible. Grid grafts are not used on the face or hands, as the goal here is to achieve the smoothest possible skin surface without a "grid pattern," taking aesthetic and functional aspects into account. In the case of extensive burns, only a limited amount of intact skin is available for split-thickness skin grafting. Alternative therapeutic options have emerged in this area over the past two decades. The culture of epidermal cells has made significant progress. In general, cells from the patient (autologous) or cells from a donor (allogeneic) can be used. These are cultured into transplantable cell clusters (cultured epithelial grafts - KET) and then transplanted—either fresh or after storage in a deep-frozen state. Since 1987, a cell laboratory under the Institute of Microbiology, Immunology, and Hospital Hygiene has been responsible for cell cultivation at our clinic. Several large laboratories worldwide now have the ability to perform this task on a contract basis. We see the indication for the use of fresh or frozen (cryopreserved) KETs from donors in deep dermal burns of grade 2b. The scab is either removed tangentially or by grinding. The donor KETs are then transplanted onto the remaining dermis, significantly stimulating wound healing—although the exact mechanism of action cannot be identified. The foreign cells are gradually replaced, at least according to current knowledge, with the patient's own epidermal cells. This method has been particularly successful so far on the face and hands, but also on the extremities for fresh burns, not only accelerating wound healing but also restoring a well-structured and acceptable skin quality. Furthermore, split-thickness skin grafts can be dispensed with and used to cover third-degree burn wounds. These KETs are also useful for third-degree burns. However, patient-derived (autologous) cultured epithelial grafts (KETs) predominate here. Allogeneic KETs can also be placed over a widely spaced mesh graft to accelerate epithelialization of the interstitial spaces (the so-called sandwich technique). It is also possible to heal third-degree burn wounds using autologous KETs alone. However, many research groups have abandoned this indication in favor of so-called "composite grafting," wound coverage with at least two components. Allograft skin is first applied to the completely necrotized wound. Often, a portion of the dermis heals within the wound. After approximately three weeks, when the autologous KETs are complete, the non-ingrown portions of the allograft skin are removed, and the KETs are placed on the wound bed. Healing success rates of up to 75% are not uncommon; the method is significantly safer than the use of autologous KETs alone. In addition to allograft skin, synthetic materials or dermis depleted of cells (immune response!) are also available today. The goal is to create a structure comparable to natural skin, namely a dermis-like component and the epidermis (KET). The development and possible variations of the options briefly discussed here are progressing at a rapid pace – while previously only a few centers explored these state-of-the-art transplantation techniques, these techniques have now led to research worldwide. Looking ahead, it should be mentioned that not only in the laboratory but also in clinical trials are already underway to transplant keratinocytes as single cells in the form of a suspension or on small carrier beads (microspheres). This has the advantage that the cells' ability to divide is preserved and the material is ready for transplantation very early, i.e., after seven to eight days.
10
Specific Treatment
Face: We allow superficial dermal burns on the face to heal spontaneously using sulfadiazine silver cream (Flammazine®). Careful wound cleansing and care of the vulnerable new skin prevent disfiguring scars. We ablate deep dermal burns early with a grinder and/or special dermatomes and treat them primarily with allogeneic keratinocyte grafts (KETs). Only any residual deficits – usually on the upper and lower eyelids – are treated with split-thickness skin. We ablate third-degree burns early with special dermatomes and cover the wound surfaces with autologous skin grafts, taking the aesthetic aspects of the facial features into account. Meticulous graft care improves graft success. Overhanging graft edges or epidermal cysts are abraded early. Acids or alkalis cause particularly deep damage and cause massive tissue shrinkage. Because they leave the most unsightly scars, they require special attention. To prevent further shrinkage, for example, of the nostrils, specially fabricated space maintainers are inserted. If further shrinkage has occurred despite early reconstructive measures, the aesthetic unit must be restored through secondary corrections with full-thickness skin grafts. Functional impairments, such as shrinkage of the mouth opening, are addressed early with angle-of-mouth widening. Shrinking nostrils are preferably restored with cartilage-skin grafts from the auricle. Burn areas on the trunk and extremities – with the exception of the hands, the female breast, and the décolleté – are predominantly treated with mesh grafts. Hands: Every possible effort must be made to preserve the hands as a functional unit. For third-degree burns, the best results are undoubtedly achieved through early excision and simultaneous coverage with split-thickness skin. The usability of the hands is noticeably impaired – sometimes even permanently – by prolonged immobilization. Scarring, particularly in the area of the long fingers, can lead to catastrophic results. The helplessness of a person with limited or lost hand function is shocking. We prioritize surgical treatment of the hands within the first five days. The best functional results are achieved during this period. We reject the use of mesh grafts, as the mesh structure is usually permanently visible and remains cosmetically unsatisfactory (leopard skin pattern). Continuous Jobst pressure treatment and intensive physical and occupational therapy, as well as a strong will on the part of the patient, are required to achieve a good outcome.