Fourth Degree Burn [ Updated ]
Burn, body damage caused by contact with fire, hot gases, other chemicals, radiation (sunlight, X rays, or radioactive ionizing radiation), or electricity. Promptly, the main consequences of contact with fire, hot water, steam, caustic materials, or electricity. There is a period of several hours until the full effects of sun or ultraviolet burns are apparent, and a period of 10 to 30 days until the full effects of ionizing radiation burns are apparent.
The extent of a burn depends in large measure on the degree of tissue damage and the volume of burned body surface. Certain factors — including the age and previous health status of the patient, the location of the burn wound and the severity of any related injuries — can also affect recovery from a burn.
A certain knowledge of skin anatomy and physiology is important for an awareness of how depth and size of a burn influence the severity of the injury. Human skin consists of two layers: an upper layer known as the epidermis, and a lower layer known as the dermis. Skin is the main organ in the body and performs a range of important functions. The principal function is to isolate the external world from the interior of the body. The epidermis, whose outer surface consists of dead, cornified cells, prevents entry into the body of infectious micro-organisms and other harmful environmental agents. By contrast, the dermis is composed of fibrous connective tissues that prevent body fluid from evaporating. The sweat glands are located within the dermis and are spreading to the skin surface. These latent transpiration, whose evaporation helps to control body temperature. Perspiration also includes small quantities of sodium chloride, cholesterol, aluminum, and urea; thus, it plays a part in regulating body fluid composition. The dermis also contains all the blood vessels and nerves in the skin, including sensory nerve endings that respond to touch, pressure, heat, cold and pain. Hence, the skin often serves as a sense organ enabling a person to adapt to changing environmental conditions. One final skin function is the synthesis of vitamin D, a compound that is important for growth and maintenance, particularly of the bone. Vitamin D is produced in the dermis from the action of sunlight on some cholesterol compounds. Destruction of the skin by deep or severe burns will affect both of these functions, causing significant complications for the patient.
Due to the extent of skin damage (see illustration), doctors have historically classified burns as first-, second-, or third-degree injuries. Just the epidermis gets affected in a first-degree burn. Such injuries are marked by redness and pain; there are no blisters, and there is minimal edema (swelling due to fluid accumulation) in the affected tissue. Strong sunburn is a typical example of a First Degree burn.
For a second-degree burn, the damage spreads across the whole epidermis and most of the dermis. Redness and blisters are typical of such injuries. The deeper the burn the more common the blisters are, which rise in size in the hours immediately after the injury. Unlike burns in the first grade, second grade injuries can be particularly painful. The development of complications and the course of cure in a second-degree burn depends on the extent of the dermis injury. Within 10 to 14 days, most minor second-degree burns recover without complications and with no scarring unless they are infected.
Third-degree burns, or full-thickness, kill the whole thickness of the skin. The wound surface is leathery, and can be brown, yellow, black, white, or red. There is no pain, since both the pain receptors and the rest of the dermis have been obliterated. Blood vessels, sweat glands, sebaceous glands and hair follicles are all damaged in the skin suffering a full-thickness burn. The loss of fluids and the metabolic disruptions associated with these injuries are severe.
Occasionally burns deeper than a complete thickness of the skin is sustained, as when part of the body is trapped in a blaze and not extricated instantly. Commonly, electrical burns are extreme burns. Such deep burns sometimes go into the subcutaneous tissue, and often into the skin, fascia and bone. These burns are of the fourth degree, also known as black (because of the traditional burn colour), or char, burns. Fourth grade burns are of serious prognosis, particularly if they involve more than a small part of the body. Toxic materials in these deep burns can be released into the bloodstream. When only a small portion of the body is involved in the char burn, it should be excised down to healthy tissue. If an extremity is involved it can require amputation.
Surgeons calculate a burn area as a percentage of total skin area of the body. The thickness of the skin on each arm is around 9 per cent of the total body, as is the skin that covers the head and neck. The ratio on each leg is 18, with 18 on the front and 18 on the back of the trunk. The amount of skin damaged influences the chances of survival. Many people can survive a second-degree burn that affects 70 per cent of their body area, but few people can survive a third-degree burn that affects 50%. If the region is down to 20 per cent, most people can be saved, but the elderly and children can struggle to survive a skin loss of 15 per cent.
Extreme burns cause acute shock to the nerves. The patient is pale, confused, nervous and terrified by the pain and can become frail. The secondary shock that comes a few hours later, is even more severe. Its main characteristics are a rapid decrease in blood pressure leading to pallor, cold extremities and subsequent collapse. This secondary shock is precipitated by the loss of fluid from circulation, not just the fluid lost in the broken tissue but the fluid that spills out of the compromised region that has lost its protective skin covering.
Burns kill not only by destroying the tissue but also by allowing this fluid and salt leakage. If the body loses more than a quarter of the blood volume, insufficient blood returns to the heart for it to sustain blood pressure. And salt loss, particularly sodium and potassium salts, not only disturbs their body balance but also changes the osmotic balance of the blood and body fluids. The significance of these physiological changes was known in 1905 but it wasn't until the 1930s that physicians were able to fix them with blood or plasma transfusions.
Of course treating a burn depends on the severity of the injury. First degree burns will usually be properly treated with sufficient first aid measures. Second-degree burns covering more than 15 percent of the body of an adult or 10 percent of the body of a infant, or affecting the face, hands, or feet, should receive immediate medical attention, as should all third-degree burns, irrespective of size.
The safest first aid after a first degree or a minor second degree burn is to immediately immerse the wound under cold tap water. That action should stop the process of burning and dissipate the heat energy from the wound. Then, the wound should be washed with mild soap and water and blotted gently dry. The burn can be left exposed after washing, provided it is minimal and can be washed regularly. If the wound is deeper, a dry, voluminous, sterile dressing can be applied over it to reduce pain and environmental exposure. Home remedies, such as butter or petroleum jelly, should not be added to the wound, as such trap heat may cause more harm inside the injury. It is also important to avoid the use of antiseptics and other harmful substances; a good rule of thumb is to refrain from applying any substance that one might be afraid to bring into one's eye.
Third-degree burns are real medical emergencies and the patient should seek treatment as soon as possible. Such wounds should not be submerged because cool water will exacerbate the circulatory shock that follows burns of third degree. You should cover the cuts with thick, sterile dressings or freshly laundered bed linens. Clothing that is sticking to the wound should not be removed, and no ointments, salves, sprays, etc. should be applied. Burned feet and legs should be lifted, and burned hands held above heart level. The breathing of the patient needs to be closely watched; if breathing ceases, artificial respiration should be provided.
The majority of burn patients taken to emergency departments in hospital are released for ambulatory burn care. Small wounds can be left exposed when regularly cleaned, as in first aid treatment; larger wounds are covered with a tight, bulky dressing. The discomfort involved in removing the dressing may be minimized by soaking it with tepid water before removal or by using a non-adhering dressing such as a bland emulsion impregnated gauze.
All patients with serious burns will be admitted into hospital. Making sure the airway (breathing passages) stays open is the first priority when treating the burn victim. Related exposure to smoke inhalation is very common, particularly when the patient has been burned in a closed space, such as a room or house. Smoke inhalation can be sustained even in patients burnt in an open field. The risk of inhalation of smoke is highest in victims who have upper torso injuries or facial burns, and in victims who cough up carbonaceous material or soot. If damage to the inhalation is possible, an anesthesiologist or surgeon passes a tube into the trachea through the patient's nose or mouth. This endotracheal tube provides for the administration of elevated oxygen concentrations and the use of a mechanical ventilator.
The next step is to treat the burn shock associated with that. This includes the insertion of intravenous lines through which resuscitating fluid can be administered; special lines to track resuscitation are also inserted in the circulation. A catheter, another index of fluid resuscitation, is inserted into the bladder to monitor urine production. Most burning centers treat the burn patient by intravenous administration of a sterile salt solution (Ringer's lactate) within the first 24 hours; this solution absorbs the fluids lost in the burn wound and from the burn wound into the area. Blood administration is typically not required because blood loss is small in most burns, and less than 10 percent of the blood results from hemolysis (i.e., red blood cell destruction). However, this hemolysis of blood can cause serious secondary injuries, particularly to the kidneys; if severe enough, it can also cause failure of the kidneys. Through quickly implementing fluid resuscitation and increasing urine production with diuretics such as mannitol, this danger can be minimised. A careful medical history is taken, and toxoid to tetanus is given.
Following this initial airway treatment and the burn shock resuscitation, a decision needs to be taken as to the patient's temperament. Normally, when the patient is admitted to a burn centre, he is put in a special tub, where the wound is washed with mild soap solutions. The wound then gets dressed. Sulfa derivatives — especially mafenide — and other antibiotics are now being used with great success in preventing burn wound infection and the subsequent spread of bacteria and toxins through the bloodstream and tissue (sepsis).
There are other issues that the burn surgeon must solve almost immediately. The continuing fluid equilibrium of the patient has to be monitored and managed, its nutritional needs have to be met, pain controlled and the burn wound itself has to be repaired. Pain is particularly troublesome in patients with partial or severe second-degree burns, which is exacerbated by the need for regular changes in dressing which physical therapy. Furthermore, pain contributes to increased release of catecholamine, which exacerbates the food requirements of the patient and the energy expenditure. Burn centers also employed creative pain management methods, including the intravenous use of morphine, the application of inadequate anesthetic medications while changing clothing, and even the use of general anesthesia during large debridges.
Nutrition may be a especially vexing issue as the food requirements are always greater than the usual fashion for the patient to consume. Therefore, intravenously administered supplemental feedings or through a feeding tube inserted in the stomach are common in treating serious burns. The use of hyperalimentation has been one of the main developments in the care of the critically burned, a technique in which complete nutritional support can be given by a catheter inserted in a large central vein.
The aims of burn lesion treatment are to prevent infection, avoid further injury to the burned tissues, and close the wound as soon as possible. The burn wound has three main treatment methods: burning, occlusive dressings, and primary excision.
Exposure therapy is recommended for exposed surfaces such as the nose, that are easily left. At first, the burn is washed, and then allowed to dry. A second-degree burn forms a layer that falls off after two to three weeks, exposing beneath minimally scarred skin. Full-thickness burns due to the overlying dead skin, or eschar, won't form a crust. The exposure treatment is aimed at softening and eliminating the eschar. Exposure helps to dry out the eschar. The saline-soaked gauzes are added to the eschar after it dries to soften it and hasten its spontaneous separation from the underlying tissues. The benefit of exposure therapy is that in heavy dressings, the patient is not immobilised. In burns that cover less than 20 per cent of the body surface, it is especially useful. The key drawback is that the protection offered by sterile dressings against infection is absent. Additionally, discomfort and heat loss in untreated wounds are greater. In general, exposure therapy is combined with the use of antibacterial creams.
More widely used in the treatment of severe burns are occlusive dressings, typically paired with topical antibacterial agents. The cream or antibacterial ointment may be applied to the patient or to the gauze. The use of occlusive dressings provides an infectious infection with a sterile barrier; the dressings also help reduce heat loss and pain. The bandages, on the other hand, must be both absorptive and occlusive, and are thus typically bulky and restrictive. In addition, the dressings have to be changed as often as every eight hours to prevent bacteria from developing in the dry, moist atmosphere of the covered wound. As noted earlier, these regular changes in dressing will increase the amount of pain and anesthetic needs.
The patient is normally submerged in a special tank in both of the above forms of wound care, where the remaining dressings and creams are washed off and the loose tissue is debridged daily. The patient is advised to step over the joints to minimize the development of scars and resulting debilitating contractures (permanent contractions of skin, muscles, and tendons).
Primary excision — that is, the surgical removal of necrotic tissues within 24 to 48 hours of the injury — is used as early as possible to prepare full thickness burns for grafting. The surgeon's primary goal after the dead skin has been removed is to cover the burned area with autographs as soon as possible — that is, grafts of the patient's own skin extracted from uninjured areas of the body. The amount of harvestable skin and the size of the possible recipient sites also differ. This disparity may be resolved by covering debridged or excised areas with skin allografts obtained from corpses, or by treating burning with xenografts (pigskin), antibiotic solutions, or special dressings of plastics. However, these steps are only reversible and the final form of treatment for most full-thickness injuries is skin autografting. Most autographs use split-thickness skin (i.e., thin slices of skin between the epidermis and part of the dermis), which the surgeon obtains from unburned areas using a dermatome tool. The face, arms, and surfaces around the joints obtain primary grafting priority. Grafts are generally dressed and sometimes inspected to ensure they are not taken.
Using topical antibacterial agents has decreased the occurrence of post-burn infection but one of the most severe complications of burns remains infection. Burn surgeons also receive cultures of burn wound and sputum and other body secretions; signs of infection are tested for these. Early detection and timely treatment of antibiotic infections and surgical debridement will mitigate their effects. Another common complication of burns are acute gastrointestinal ulcers; they occur as small, circumscribed lesions within the stomach lining or duodenum. Endoscopy can diagnose these ulcers and are treated with antacids and medications that reduce the amount of acid secretion.
The incidence of post-burn seizures is a rare complication for infants. Such seizures can result from imbalances in the electrolyte, an abnormally low blood oxygen levels, infection, or medications. In about a third of cases, the cause is unknown. Post-burn hypertension is also very peculiar to kids and is possibly linked to catecholamine release and other stress hormones.
The development of fibrous masses of scar tissue called hypertrophic scars and keloids is a common complication of deep dermal burns and skin grafts. In brown-skinned breeds this complication is especially common. Reddened, inflamed tissue is biologically active; it has a rich vascular supply, producing collagen, the main wound protein, and the major component of scars, rapidly. Constant pressure on inflamed tissue increases blood flow and collagen content, reducing hypertrophic scars and keloids. Tailor-made splints, gloves, stockings, and body jackets will provide the strain. In special cases skeletal traction can be important.
Respiratory conditions in burn patients rate as the leading cause of death. Potentially fatal breathing complications include inhalation trauma, unconscious patient ingestion of fluids, bacterial pneumonia, pulmonary edema, pulmonary artery obstruction, and respiratory failure post-injury. Direct-inhalation injuries are especially common, and can lead to other respiratory complications. Dry heat and soot inhalation, carbon monoxide poisoning, and cigarette inhalation are the three main types of direct-inhalation injuries.
Any patient suspected to have sustained complications from the inhalation will undergo a bronchoscopic airway test. This exam can reveal the degree of respiratory injury and help with the planning of the appropriate treatment. Constant one-on-one nursing care is also needed to provide the pulmonary treatment necessary. In most cases, an endotracheal tube is inserted into the lungs, and a mechanical ventilator is mounted on the patient. The ventilator helps to keep the lungs inflated by supplying air under continuous pressure; this aids in the management and prevention of atelectasis (collapse of air sacs). You may also use the ventilator to re-expand damaged lungs. In addition, the system will convey the inspired air to varying concentrations of oxygen and mists. The high concentrations of humidified oxygen are provided to patients who have suffered from smoke inhalation. Those with carbon monoxide poisoning obtain 100 per cent oxygen before their carboxyhemoglobin blood level drops below 20 per cent.
The most common aftereffects of severe burns are physically and cosmetically painful scars. These scars also need additional plastic surgery to remove contractures over joints — sometimes years after the initial skin grafting — and to produce satisfactory cosmetic results. Realistically, the results are almost never as good as the pre-injury state of the patient. Most burn scars are unsightly, and while the patient may hope for practical improvement, complete reconstruction is not generally possible.
Burn wounds merit special consideration. The patient should stop having the wounds exposed to sunlight. Scars should be covered by an ultraviolet screening agent (a sunblock) in areas which are often exposed to the sun, such as the face and hands. Since full-thickness burns may kill sweat glands, sebaceous glands, and hair follicles, lanolin and other emollient creams and lotions will need to be applied to the scarred skin to avoid drying and cracking, and to minimize itching.
Many victims of serious burns face years of sometimes painful physical therapy as they try to regain or maintain movement in burned joints. The psychological adjustment to the disfigurement may be stressful, and many patients need intensive therapy to deal with their altered appearance and physical disability. But even seriously burned burn victims can make positive improvements and lead productive lives with the aid of supportive family, friends and professionals.