Burn injuries are underappreciated injuries that cause significant morbidity and death. Burn injuries, particularly severe burns, are associated with an immunological and inflammatory response, metabolic abnormalities, and distributive shock, all of which can be difficult to control and can lead to multiple organ failure.
Despite a significant drop in their global frequency, burn injuries remain one of the most prevalent types of trauma and account for a significant number of trauma patients in health-care crises across the world.
What is Burn injuries?
Burns are tissue injury caused by heat, overexposure to sunlight or other forms of radiation, or chemical or electrical contact. Burns can cause minor medical issues as well as life-threatening crises. The treatment of burns is determined on the location and degree of the injury.
Burn injuries cause physical and psychological scars for the rest of one's life, causing pain and altering mental health, quality of life, capacity to return to employment, and future death. Although data on burn epidemiology is critical for resource allocation and prevention, the data that is available is varied and inconsistent.
The majority of the data originate from high-income nations and are directly connected to access to health-care resources, environmental variances, and the resources of diverse health-care systems. Fewer resources, geographical limits, and cost all limit data collecting and access to health care in low-income nations. Regional diversity is also influenced by cultural variables such as open-air cooking areas and loose clothes, domestic abuse, and dowry deaths.
Although burn injuries are decreasing in high-income nations, the frequency of burn injuries remains high elsewhere, with low- and middle-income areas accounting for 90 percent of all burns. According to the WHO, 11 million burn injuries of all varieties occur globally each year, 180,000 of which are fatal. The occurrence of burn injuries varies greatly. The majority of injuries are sustained by young children (1–15.9 years old) and those of working age (20–59 years old).
According to the American Burn Association (ABA) National Burn Repository 2019, flame burns continue to account for the bulk of injuries in the United States (41 percent), with scalds coming in second at 31 percent. Chemical (3.5%) and electrical burn injuries (3.6%) are substantially less prevalent. Burns in children under the age of five are often scald injuries, with flame-related burns increasing with age. Burns among the older population are on the rise all over the world, and the majority of them are caused by fire. Scald injuries, on the other hand, are on the rise. Finally, burn injuries are more common in particular vulnerable populations, such as those with epilepsy, depending on the surroundings.
Skin Anatomy and Function
Skin is the largest organ of the body. It has 3 major tissue layers.
The epidermis, the outermost layer, is made up of stratified epithelium. The epidermis consists of two layers: an exterior layer of anucleate cornified cells (stratum corneum) that covers inner layers of viable cells from which the cornified surface cells differentiate.
The dermis lies under the epidermis and is made up of a thick fibroelastic connective-tissue stroma comprising collagen and elastic fibers, as well as an extracellular matrix known as ground material. This amorphous matrix is composed of an acid mucopolysaccharide protein, salts, water, and glycoproteins; it may contribute to salt and water balance, act as a support for other dermal and subcutaneous tissue components, and engage in collagen creation.
- Subcutaneous tissue
Subcutaneous tissue, the third layer of skin, is mostly made up of areolar and fatty connective tissue. This layer's thickness and adipose content vary greatly throughout the country. Skin appendages, glands, and hair follicles are all present.
External causes of burns include thermal (heat-related), chemical, electrical, and radiation sources. The following are the most prevalent causes of burns in the United States:
- Fire or flame (44%),
- Scalds (33%),
- Hot objects (9%),
- Electricity (4%), and
- Chemicals (3%).
The majority of burn injuries (69 %) occur at home or at work (9 %), and the majority are unintentional, with 2 percent caused by another's attack and 1–2 percent caused by a suicide attempt. In roughly 6% of cases, these sources can cause inhalation damage to the airway and/or lungs.
Burn injuries are more prevalent in the impoverished. Other risk factors include smoking and drunkenness. Colder climates have a higher rate of fire-related burns. Cooking over open flames or on the floor, as well as developmental problems in children and chronic illnesses in adults, are specific risk factors in the poor world.
Within a few hours of damage, severe burns (regardless of origin) result in the establishment of a severely dysregulated inflammatory host response. The inflammatory and stress reactions are distinguished by increased amounts of cytokines, chemokines, and acute phase proteins, as well as a hypermetabolic state caused by a prolonged sympathetic tone that can last beyond the acute phase of treatment.
Depending on the severity of the damage, the first host response following severe burn injury is comparable to that following many other inflammatory illnesses induced by tissue loss, such as trauma or major surgery, which aids in the initiation of tissue repair and overall wound healing.
However, with severe burns, the inflammatory cascade may be activated numerous times during clinical treatment after initial resuscitation, such as during burn surgery or later infection problems. When the inflammatory cascade happens frequently or goes unchecked, it has the potential to harm host tissue and contribute to organ failure and death. Although numerous components of the complicated response to burn injury have been discovered, how and in what order these components interact has not been determined.
Evaluation of the Burn Wound
After the patient has been thoroughly examined and stable hemodynamics and gas exchange have been established, thoroughly examine the burn site. Assess burn wounds for extent, depth, and circumferential components first. This information is used to make decisions about the kind of monitoring, wound care, hospitalization, and transfer. The following are the American Burn Association's burn center transfer criteria:
- Second- or third-degree burns greater than 10% total body surface area (TBSA) in patients younger than 10 years or older than 50 years
- Second- or third-degree burns greater than 20% TBSA in persons of other age groups
- Second- or third-degree burns that involve the face, hands, feet, genitalia, perineum, or major joints
- Third-degree burns greater than 5% TBSA in persons of any age group
- Electrical burns, including lightening injury
- Chemical burns
- Inhalational injury
- Burn injury in patients with preexisting medical disorders that could complicate management, prolong recovery, or affect mortality
Extent of burn
A precise estimation of burn size is required for treatment and transfer decisions. There are several methods for estimating the size or scope of a fire. The age-specific chart based on the Lund-Browder diagram, which accounts for variations in body proportions with growing, is perhaps the most accurate. A burn is painted on a cartoon character, and the body surface area affected is calculated using an age-specific chart.
Adults can use the "rule of nines" as an alternative. Because children's body proportions differ from those of adults, this is less accurate. The palmar surface of the patient's hand can be utilized to treat regions with uneven or nonconfluent burns. The region of the palm without fingers accounts for 0.5 % of the body surface throughout a wide age range.
During the initial assessment, burn depths are frequently underestimated. Devitalized tissue may look alive for some time after damage, and in the wound perimeter, some degree of progressive microvascular thrombosis is frequently detected. As a result, the appearance of the wound alters in the days following damage. Serial evaluation of burn wounds can be quite beneficial.
Burn depth is classified as first, second, third, or fourth degree, as follows:
- Burns in the first degree are typically red, dry, and painful. Burns that are first labeled as first-degree are frequently superficial second-degree burns that peel the next day.
- Second-degree burns are frequently red, moist, and excruciatingly painful. Their depth, capacity to heal, and proclivity to create hypertrophic scars all vary greatly.
- Third-degree burns have a leathery consistency, are dry, insensate, and waxy. These wounds will not heal until they are contracted and limited epithelial migration occurs, resulting in a hypertrophic and unstable cover. Both second- and third-degree burns can be covered up by burn blisters. The treatment of burn blisters is still debatable, however undamaged blisters aid significantly with pain relief. If an infection develops, debride the blisters. Please see the photographs below.
- Fourth-degree burns affect the subcutaneous tissue, tendon, or bone beneath the skin. During the early stages of an examination, even an experienced examiner may have difficulties precisely determining burn depth. In general, burn depth is overestimated during the initial assessment.
Complications of Burn
- Inhalation injury
A history of closed-space exposure, face burns, singed nose hairs, and carbonaceous material in the mouth, throat, or sputum are used to make the clinical diagnosis of inhalation damage. Until problems (typically infection) emerge, chest radiograph results are normally normal. Carbonaceous material, ulceration, or erythema may be discovered during a bronchoscopy, although these changes are not always visible.
Upper airway edema, bronchospasm, small airway blockage, increased dead space and intrapulmonary shunting, reduced lung and chest wall compliance, and infection are among clinical outcomes of inhalation damage. Management is only supportive.
- Electrical burns
Compartment syndrome, cardiac arrhythmia, or myoglobinuria are uncommon in individuals exposed to fewer than 500 volts, however patients suffering medium injuries (200-1000 V) can incur catastrophic local damage. Loss of consciousness, falls, fractures, myoglobinuria, compartment syndrome, and arrhythmia are all frequent symptoms of high-voltage injuries, and these people should be treated as trauma patients.
- Chemical burns
The treatment of chemical exposures should begin with the removal of all clothing and chemicals as soon as possible. First responders must take precautions to avoid injuries. After that, a thorough irrigation with tap water should be conducted for at least 30 minutes. Alkaline compounds take longer to remove because they are less soluble in water. Consultation with poison control center experts should be considered when examining anyone with a chemical burn. Topical ocular anesthetics can help with adequate ocular irrigation. Fluid resuscitation may be necessary in the case of severe injuries. Some agents are linked with unpleasant vapors, which might impair the airways.
- Facial burns
The deep sweat and sebaceous glands of the central face, particularly in teenagers and adults, make it likely that most second-degree burns will heal successfully with sufficient topical wound care. There are several suitable treatment alternatives available, such as topical silver sulfadiazine or bland antibiotic ointments. Topical ophthalmic antibiotic ointments can be used to treat burns around the eyes. If grafting is an option, save thick donor skin with a good color match for face resurfacing. The "blush" regions, such as the upper back and shoulders, are frequently suitable face donor locations.
The most critical aspect of treating seriously burnt ears early is avoiding auricular chondritis. This is a severe complication in which the cartilage becomes inflamed and liquefies fast. Twice-daily washing and the use of topical mafenide acetate, which penetrates the eschar, can help to alleviate the problem. The extent of damage determines subsequent ear care.
- Hand burns
Hand burns are given top consideration from the start of treatment. Adequate blood flow must be maintained throughout the first 24-48 hours. Monitor consistency, temperature, and the presence of pulsatile flow on a regular basis (detectable using Doppler studies of the digital pulp). If blood flow is suspect, escharotomy or fasciotomy should be performed.
Splint the hands in a functional posture, with the metatarsophalangeal joints at 70-90°, the interphalangeal joints in extension, the first web space open, and the wrist at 20° of extension. Elevate the hands to reduce edema, and have the patient do range-of-motion exercises twice daily with a therapist. Deep dermal and full-thickness burns should be excised early and closed with a sheet autograft. Hand treatment should be continued throughout the healing period, with the exception of the few days following grafting. If this is not done, the long-term function will be suboptimal.
Before treatment of the burn wound can begin, the patient must be thoroughly examined. This is frequently a quick endeavor, especially in individuals with little, simple wounds. Evaluation of the wound is generally secondary in patients with bigger burns. The American College of Surgeons Committee on Trauma categorizes evaluation of the burn patient as a main and secondary survey.
- Primary survey
The technique of the American College of Surgeons Advanced Trauma Life Support course should be used to examine burn patients in a methodical manner. The major survey describes this examination, with an emphasis on airway support, gas exchange, and circulatory stability. First, assess the airway; this is especially important in burn victims. Early detection of impending airway compromise, followed by quick intubation, can save a patient's life. After obtaining suitable vascular access and implanting monitoring devices, do a thorough trauma survey that includes the required radiographs and laboratory testing.
- Secondary survey
Following that, burn patients should undergo a burn-specific secondary survey, which should include determining the mechanism of injury, assessing the presence or absence of inhalation injury and carbon monoxide intoxication, examining for corneal burns, considering the possibility of abuse, and performing a detailed assessment of the burn wound.
It is especially important to obtain a complete history at the initial evaluation and to transfer this information with the patient to the next level of care. A history of closed-space exposure and soot in the nares and mouth is used to diagnose inhalation damage. Carbon monoxide poisoning is likely among people injured in building fires, especially if they are obtunded; carboxyhemoglobin values in those ventilated with oxygen might be deceiving.
Persons with face burns should have their corneas examined carefully before developing lid swelling, which can make inspection difficult. Begin fluid resuscitation after evaluating the burn site and making decisions about outpatient or inpatient care or transfer to a burn center.
- Fluid resuscitation
For the first 18-24 hours following injury, burn patients have a graded capillary leak that rises with damage size, a delay in initiating resuscitation, and the existence of inhalation injury. Fluid resuscitation can only be loosely guided by formulae since the alterations in each patient are unique. Due to the inherent inaccuracy of formulae, infusions based on resuscitation objectives must be reevaluated and adjusted on a constant basis.
During the first 24 hours, most formulas prescribe that all crystalloids be isotonic, typically Ringer lactate solution. Although hypertonic saline has been advocated for resuscitation, this practice has mostly been abandoned due to technical difficulties and a lack of improved clinical results. Hypoglycemia is a risk in smaller children, whose gluconeogenetic capability is undeveloped, and Ringer lactate solution with 5% dextrose should be supplied at a maintenance rate.
The modified Brooke or Parkland formulae are acceptable consensus formulas for determining the starting volume of infusion. In the first 8 hours after an injury, half of the entire estimated 24-hour volume is provided. If the resuscitation is delayed, this amount is given such that the infusion is finished by the end of the eighth hour after the accident. Following resuscitation objectives, capillary integrity normally restores after 18-24 hours, and fluid delivery should be reduced. Colloid administration, typically 5% albumin in Ringer lactate solution, is helpful at this time. In patients with significant deep burns, physicians are increasingly supplementing a portion of the predicted crystalloid with 5% albumin.
As a general rule, burns that cover less than 15% of the body surface area are not linked with a large capillary leak, and children with these burns can be managed with fluid delivered at 150 percent of a predicted maintenance rate and regular monitoring of their hydration status. Those who are able and willing to take fluid orally may be given fluid orally, with extra fluid supplied intravenously at a maintenance rate.
- Burn Wound Management
Because glove powders have been shown to be hazardous to tissue, the burn team performs all wound treatment with powder-free gloves. The first step in treating a burn wound is to clean it with saline or one of many commercially available detergents. Blisters that have ruptured are cut out using scissors. After washing the wound, apply a topical antimicrobial treatment.
Topical antibiotics inhibit microbial development and hence prevent invasive infection. Systemic antibiotics are not advised as a preventive measure since they do not prevent wound sepsis. When cellulitis is seen in adjacent unburned tissue, systemic antibiotics may be recommended.
- Burn pain management
Controlling pain is critical to the healing of burn victims. Inadequate pain control slows the healing process because fear and worry cause an increase in stress hormones (such as glucocorticoids). As a result of the absence of pain control, the physical and psychological consequences, as well as the hospital stay, endure longer.
Burn pain has three basic mechanisms: nociceptive, neuropathic, and inflammatory. Intravenous morphine remains the cornerstone of pain therapy; yet, shorter half-life opioids and nerve blocks remain viable alternatives. Wound debridement, physiotherapy, and dressing changes all significantly raise pain levels throughout the healing process. Scar maturation and ongoing physical treatment reduce nociceptive discomfort. Pregabalin and gabapentin are commonly used to treat neuropathic pain.
Remove the fine mesh gauze and clean the burn wound with saline or poloxamer 188 if the burn wound has a purulent discharge. One approach is to apply silver sulfadiazine cream to the burn site twice daily and cover it with sterile roller gauze covering. Instruct the patient to gently wash the burn wound with clean water to remove the cream before adding more cream.
Multiple layers of topical cream develop on the burnt skin and predispose the area to infection if the cream is not thoroughly removed at each dressing change. In the absence of surrounding cellulitis, the wounds can be managed with wet-to-dry dressings on a regular basis. Wounds with moderate cellulitis around them should be treated similarly, with the addition of oral antibiotics.
Rehabilitation and rebuilding are the ultimate stages of burn therapy. This discipline has grown swiftly, becoming increasingly specialized as survival has improved. Therapy should begin in the critical care situation, with range, splinting, and antideformity placement as top objectives. Ranging should be done twice a day, with the therapist moving all joints through a passive range of motion.
These activities aid in the prevention of several common contractures. Priorities for the severely burnt patient as he or she begins to heal include maintaining passive ranging, increasing active ranging and strengthening, reducing edema, pursuing activities of daily living, and preparing for employment, play, and school.
Following discharge, important parts of rehabilitation are continuous and gradual range and strengthening, postoperative treatment following reconstructive surgery, and scar maintenance. Deep dermal burns that heal spontaneously in less than 3 weeks have the most problematic hypertrophic scarring. Scar massage, compression garments, topical silicone, steroid injections, and pruritus control are all used to reduce hypertrophic scarring after burns have healed completely.
Most patients have positive long-term results if they participate in a coordinated multidisciplinary burn aftercare program. According to the Life Impact Burn Recovery Evaluation (LIBRE) research, survivors who were burnt as children had long-term social involvement results similar to those of survivors who were burned as adults.
Burns can be avoided. High-income nations have made significant progress in decreasing burn fatality rates through a mix of preventative efforts and advancements in burn treatment. The majority of these breakthroughs in prevention and care have only been partially implemented in low- and middle-income nations. Increased efforts in this area would very certainly result in considerable decreases in rates of burn-related mortality and disability.
Prevention initiatives should target the risks of specific burn injuries, as well as education for vulnerable populations and community training in first aid. A multi-sectoral burn prevention strategy should involve extensive initiatives to:
- Improve awareness
- Develop and enforce effective policy
- Describe burden and identify risk factors
- Set research priorities with promotion of promising interventions
- Provide burn prevention programs
- Strengthen burn care
- Strengthen capacities to carry out all of the above.
A burn is a form of tissue injury produced by heat, cold, electricity, chemicals, friction, or UV radiation (like sunburn). The majority of burns are caused by heat from hot liquids (known as scalding), solids, or fire. While male and female rates are comparable, the underlying factors frequently differ. In certain locations, open cooking flames or faulty cook stoves pose a risk to women. Risk is associated with work situations among males. Other risk factors include alcoholism and smoking. Burns can also arise as a result of self-harm or interpersonal aggression (assault).
Burns are almost always avoidable. Treatment is determined on the degree of the burn. Superficial burns may require little more than pain medicine, but serious burns may necessitate extended treatment in specialist burn clinics. Chilling with tap water may alleviate discomfort and reduce damage; but extended cooling may result in a drop in body temperature.
Cleaning partial-thickness burns with soap and water, followed by dressings, may be necessary. It is unclear how to treat blisters, although it is generally safe to let them alone if they are little and drain them if they are large. Full-thickness burns frequently necessitate surgical procedures such as skin grafting. Due to capillary fluid leaks and tissue swelling, extensive burns frequently need substantial quantities of intravenous fluid. Infection is the most prevalent consequence of burns. If not up to date, tetanus toxoid should be administered.