**5. Etiology**

At least 44°C of heat is required for the skin to be burned. Besides, the duration of the heat is also important; transepidermal necrosis occurring with 70°C of heat in a second, occurs in 45 minutes with 47°C of heat [4].

Burns can be grouped according to thermal, chemical, electricity, and radiation [12]. The causative of burns should be known since a different treatment protocol is applied in each case. Thermal burns that occur with direct effects of flames with high levels of heat, contact with hot objects, hot liquids, or hot vapors are commonly seen. The duration of the contact and the degree of the temperature determine the degree of cell damage [1]. Chemical burns due to acid or alkali salts and solutions may cause burns due to corrosive effects of these substances. Other than these, burns can also develop due to electrical current, radiation, ultraviolet, and laser rays [4]. Serious burns due to flames of weapons, explosives, and combustibles can occur during warfare [12].

#### **5.1. Thermal burns**

It develops in two different ways as hot water and flame burns. Thermal burns are skin injuries caused by excessive heat, typically from contact with hot surfaces, hot liquids, steam, or flame. Thermal damage to skin results in cellular death as a function of temperature and length of contact time. Thermal burns are the most common type of burn injuries, making up about 86% of the burned patients requiring burn center admission. About 70% of the burns in children develop due to hot water. It is most often caused by hot drinks or hot bath water. These burns are usually first-degree or superficial second-degree burns [13, 14]. Flame burns account for 50% of adult burns [14]. Inhalation burn may also develop together with it. It usually appears as a second or third-degree burn.

be many unwanted effects of absorbed phosphorus, delirium, psychosis, convulsions, coma; hepatomegaly, jaundice; proteinuria, acute tubular necrosis; thrombocytopenia, hypopro-

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Other than these, burns due to coal tar can also develop, especially in the treatment of psoriasis. Tar is an industrial material used in road cladding and roof isolation [17]. It is obtained by dry distillation from organic substances, has a liquid oil consistency and is a water-insoluble substance. The boiling point reaches up to 232°C. This may cause severe burns. In the literature, it has been shown that the majority of hot tar burns often occur in the workplace in male workers with accidents [18]. Continuation of the skin contact with tar causes the heat transfer to continue and leads the burn to progress. Therefore, the tar should be removed from the body in a short time. In the literature, successful cases have been reported in which unsterilized sunflower oil, olive oil, as well as lanolin and surfactant-containing creams and other antibiotic creams were used [19]. Again, in the tar adhered skin zone, the ice cubes were left for 10–20 minutes, and the tar was frozen and

Chemical burns due to mercury-containing substances can cause blistering (bullae). Blisters

Electric burns, which are most common in men between 20 and 40 years of age, constitute 20% of burn-related mortalities [15]. It occurs by electric current or lightning strike. Low-voltage electrical burns are considered to be less than 1000 volts and high-voltage electrical burns are considered to be more than 1000 volts; electrical burns between 250 and 1000 volts should be followed up just like high-voltage electrical burns since these patients may develop uncon-

In low-voltage accidents, burns are limited on the skin, however, go down into deeper tissues. In high-voltage accidents, there are traces just like stapler pierce, ulceration, and scarring. In the lightning strike, necrotic areas start from where the current entered and progress along the line [4]. As a result of direct contact with the electricity, systemic complications such as cardiac arrhythmia, necrotic areas in the soft tissues and bones may develop as well as ther-

It is caused by the uptake of radioactive material. The local radiation burns caused by high radiation doses (8–10 Gy) are similar to thermal burns except for several days to weeks of delayed latency. Taking high doses causes sudden cell death. The most sensitive tissues to radiation are lymphocytes and hematopoietic cells. The degree of radiation damage depends on the dose [20]. Erythema on the skin is the earliest finding. After weeks of exposure to high-

Although it is not dependent on excessive heat or flame, sunburns and frostbites should be

sciousness, compartment syndrome, and myoglobinuria/hemoglobinuria [15].

must be excised because mercury is found in the bullae liquid.

mal damage as the current passes through the whole body.

dose radiation, necrosis and ulceration of the skin may develop.

considered in the integrity of the burn etiology.

thrombinemia, ventricular arrhythmia, and myocarditis may develop [4, 14].

separated in the form of a crust.

**5.3. Electrical burns**

**5.4. Radiation burns**

#### **5.2. Chemical burns**

It is the cause of burns caused by cleaning materials that are used in daily life at home or by work accidents. While 3–6% of all burns constitute chemical burns, they constitute 14–30% of burn-related mortalities [15]. Generally, it is developed due to contact with strong acid or alkaline substances. Unlike thermal burns, there is longer contact with the agent. Inhalation or ingestion of the chemical material may result in systemic symptoms and injuries in the mouth, esophagus, and stomach where it contacts. Bleach, cement, plaster, and hydrofluoric acid used in glassware artwork, phenol, and petroleum-derived organic compounds, phosphorus used in the construction of various warfare materials are the most common reasons of chemical burn incidents [12].

Acid burns tend to limit themselves. Hydrofluoric acid is one of the most frequently used acids for construction of electrical circuits and for scraping paintings on glass and that causes burn most [16]. Hydrofluoric acid passes quickly through the skin and continues to damage tissue until it reaches a tissue rich in calcium, such as bone. Even small hydrofluoric acid burns may develop hypocalcemia, which is sufficient for cardiac effects to occur. More than 10% hydrofluoric acid may be fatal. The gels containing calcium gluconate can be administered topically, or IV calcium gluconate can be given in severe cases [16].

Bleach, oven cleaners, fertilizer, cement, plaster, and lime contact result in basic burns. Bases penetrate deep into the tissue, combine with cutaneous lipids to form soap, and continue to dissolve the skin until neutralized. Pain in the base burns occurs late, which delays first aid. Base burns are more dangerous than acid burns [16].

Phenol and petroleum-derived compounds are organic compounds. They break down proteins by direct reactions or production of heat [14].

Compounds containing sodium, phosphorus, lithium, and chlorine are inorganic compounds. They cause skin damage by direct bonding and salt formation [14].

Some modern bombs contain white phosphorus. When this element comes into contact with air, it burns and the oil-soluble phosphorus fragments are scattered across the wound and spread through the subcutaneous fat tissue. As long as phosphorus is in contact with oxygen, it continues to burn, and therefore phosphorus burns are deep and painful, may extend to the bone. Local treatment is more urgent than conventional burns. Phosphorus burns must be prevented from contacting with air; it should be isolated by wrapping the wound with wet dressings or by immersing the affected areas in water. It should not be allowed to remain dry at any times. Phosphorus can cause hypocalcemia and hyperphosphatemia. There may be many unwanted effects of absorbed phosphorus, delirium, psychosis, convulsions, coma; hepatomegaly, jaundice; proteinuria, acute tubular necrosis; thrombocytopenia, hypoprothrombinemia, ventricular arrhythmia, and myocarditis may develop [4, 14].

Other than these, burns due to coal tar can also develop, especially in the treatment of psoriasis. Tar is an industrial material used in road cladding and roof isolation [17]. It is obtained by dry distillation from organic substances, has a liquid oil consistency and is a water-insoluble substance. The boiling point reaches up to 232°C. This may cause severe burns. In the literature, it has been shown that the majority of hot tar burns often occur in the workplace in male workers with accidents [18]. Continuation of the skin contact with tar causes the heat transfer to continue and leads the burn to progress. Therefore, the tar should be removed from the body in a short time. In the literature, successful cases have been reported in which unsterilized sunflower oil, olive oil, as well as lanolin and surfactant-containing creams and other antibiotic creams were used [19]. Again, in the tar adhered skin zone, the ice cubes were left for 10–20 minutes, and the tar was frozen and separated in the form of a crust.

Chemical burns due to mercury-containing substances can cause blistering (bullae). Blisters must be excised because mercury is found in the bullae liquid.

#### **5.3. Electrical burns**

or flame. Thermal damage to skin results in cellular death as a function of temperature and length of contact time. Thermal burns are the most common type of burn injuries, making up about 86% of the burned patients requiring burn center admission. About 70% of the burns in children develop due to hot water. It is most often caused by hot drinks or hot bath water. These burns are usually first-degree or superficial second-degree burns [13, 14]. Flame burns account for 50% of adult burns [14]. Inhalation burn may also develop together with it. It usu-

It is the cause of burns caused by cleaning materials that are used in daily life at home or by work accidents. While 3–6% of all burns constitute chemical burns, they constitute 14–30% of burn-related mortalities [15]. Generally, it is developed due to contact with strong acid or alkaline substances. Unlike thermal burns, there is longer contact with the agent. Inhalation or ingestion of the chemical material may result in systemic symptoms and injuries in the mouth, esophagus, and stomach where it contacts. Bleach, cement, plaster, and hydrofluoric acid used in glassware artwork, phenol, and petroleum-derived organic compounds, phosphorus used in the construction of various warfare materials are the most common reasons of

Acid burns tend to limit themselves. Hydrofluoric acid is one of the most frequently used acids for construction of electrical circuits and for scraping paintings on glass and that causes burn most [16]. Hydrofluoric acid passes quickly through the skin and continues to damage tissue until it reaches a tissue rich in calcium, such as bone. Even small hydrofluoric acid burns may develop hypocalcemia, which is sufficient for cardiac effects to occur. More than 10% hydrofluoric acid may be fatal. The gels containing calcium gluconate can be adminis-

Bleach, oven cleaners, fertilizer, cement, plaster, and lime contact result in basic burns. Bases penetrate deep into the tissue, combine with cutaneous lipids to form soap, and continue to dissolve the skin until neutralized. Pain in the base burns occurs late, which delays first aid.

Phenol and petroleum-derived compounds are organic compounds. They break down pro-

Compounds containing sodium, phosphorus, lithium, and chlorine are inorganic compounds.

Some modern bombs contain white phosphorus. When this element comes into contact with air, it burns and the oil-soluble phosphorus fragments are scattered across the wound and spread through the subcutaneous fat tissue. As long as phosphorus is in contact with oxygen, it continues to burn, and therefore phosphorus burns are deep and painful, may extend to the bone. Local treatment is more urgent than conventional burns. Phosphorus burns must be prevented from contacting with air; it should be isolated by wrapping the wound with wet dressings or by immersing the affected areas in water. It should not be allowed to remain dry at any times. Phosphorus can cause hypocalcemia and hyperphosphatemia. There may

tered topically, or IV calcium gluconate can be given in severe cases [16].

They cause skin damage by direct bonding and salt formation [14].

Base burns are more dangerous than acid burns [16].

teins by direct reactions or production of heat [14].

ally appears as a second or third-degree burn.

**5.2. Chemical burns**

20 Hot Topics in Burn Injuries

chemical burn incidents [12].

Electric burns, which are most common in men between 20 and 40 years of age, constitute 20% of burn-related mortalities [15]. It occurs by electric current or lightning strike. Low-voltage electrical burns are considered to be less than 1000 volts and high-voltage electrical burns are considered to be more than 1000 volts; electrical burns between 250 and 1000 volts should be followed up just like high-voltage electrical burns since these patients may develop unconsciousness, compartment syndrome, and myoglobinuria/hemoglobinuria [15].

In low-voltage accidents, burns are limited on the skin, however, go down into deeper tissues. In high-voltage accidents, there are traces just like stapler pierce, ulceration, and scarring. In the lightning strike, necrotic areas start from where the current entered and progress along the line [4]. As a result of direct contact with the electricity, systemic complications such as cardiac arrhythmia, necrotic areas in the soft tissues and bones may develop as well as thermal damage as the current passes through the whole body.

#### **5.4. Radiation burns**

It is caused by the uptake of radioactive material. The local radiation burns caused by high radiation doses (8–10 Gy) are similar to thermal burns except for several days to weeks of delayed latency. Taking high doses causes sudden cell death. The most sensitive tissues to radiation are lymphocytes and hematopoietic cells. The degree of radiation damage depends on the dose [20]. Erythema on the skin is the earliest finding. After weeks of exposure to highdose radiation, necrosis and ulceration of the skin may develop.

Although it is not dependent on excessive heat or flame, sunburns and frostbites should be considered in the integrity of the burn etiology.

#### **5.5. Sunburns**

It develops due to uncontrolled and prolonged exposure to sun or light sources containing UVB. Sunburn is the contact dermatitis due to ultraviolet B rays (295–315 nm), which is the most erythematous wavelength. The formation of sunburn requires more ultraviolet light than the minimal erythematous dose (MED) [10]. While 20 minutes is enough to get a minimal erythematous dose (MED) in a clear summer day, 1 full day sunbathing is needed to reach 20 times the MED dose. People reaching this dose have sunburns with individual differences. The skin reaction starts at 4–6 hours and ends at 72 hours [4].

Burn injury causes both local and systemic changes. Vasodilatation and vascular permeability are also increased in the skin and subcutaneous tissues due to local reaction. As a systemic response, all internal organ systems are affected **(Figure 1).** In severe burns, cytokines and other inflammatory mediators are released in excess both in the burn area and in the unburned areas. These mediators cause vasoconstriction and vasodilatation, increase in capillary permeability, and development of edema both in the burn site and in remote organs. Pathological changes occur in metabolic, cardiovascular, renal, gastrointestinal, and coagulation systems. With burn shock, blood volume and cardiac output are decreased, renal blood flow and glomerular filtration rate decrease, gastrointestinal mucosal atrophy develops and intestinal permeability increases. Catabolism is accelerated and often results in widespread microthrombosis [14, 25]. When the burn occurs, three damage zones are described as local changes in the skin. These regions were first described by Jackson in 1947 [13]. It consists of coagulation (necrosis) zone, stasis (ischemia) zone and the outermost hyperthermia (inflammation) zone (**Figure 2**). The innermost region is the area closest to the heat source and the one with the greatest damage. Coagulation of structural proteins that develop in this region results in irreversible tissue injury. The area outside this region is called the stasis (ischemic) zone. In this area, tissue perfusion has reduced but is a layer of living tissue. Cells in this area can be saved if treatment is done to increase tissue perfusion. Otherwise, progressive ischemia and necrosis develop within 24–48 hours [13]. The third and outermost zone is hyperemia (inflammation) zone. Tissue perfusion is increased in this region and is characterized by vasodilation due to the

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**Figure 1.** Systemic changes that occur after a burn injury.

#### **5.6. Cold burn (frostbite)**

It is developed with cooling of the body. The skin is frozen at −2 to −10°C and irreversible changes occur under −22°C. Cold burn is different from thermal burns; trauma occurs at the cellular level and extracellular fluid directly, at the organ functions indirectly [21]. Electrolyte concentration increases with development of ice crystals in the intracellular and extracellular fluid, enzyme systems do not work and tissue destruction begins [4]. Vasoconstriction endothelial damage and thromboembolism increases ischemia and failure [21]. Prostoglandins are primarily responsible cytokines. In the first-degree frostbite, firstly, reflex erythema starts against cold, then vasoconstruction and paleness are seen. In the second-degree frostbite, erythema, edema, and subepidermal bullae, in the third-degree frostbite, blue-black color changes and hardening are observed [4]. It is usually seen at the outer regions such as ear, nose, and fingers [10]. Ischemia developed in the tissue and is spread to the body.

Besides these burn types, other rare burn traumas have been reported. There are also types of burns that are common in eastern societies and are associated with low socio-cultural level. As an alternative to modern medicine, particularly those commonly used in muscle joint disorders, include herbal applications and cupping therapy [22].
