Thermal burn

A thermal burn is a type of burn resulting from making contact with heated objects, such as boiling water, steam, hot cooking oil, fire, and hot objects. Scalds are the most common type of thermal burn suffered by children, but for adults thermal burns are most commonly caused by fire.^[1] Burns are generally classified from first degree up to fourth degree, but the American Burn Association (ABA) has categorized thermal burns as minor, moderate, and major, based almost solely on the depth and size of the burn.^[2]

Pathophysiology

There are three (or sometimes four) degrees of burns, in ascending order of severity and depth. For more info, see Burn#Signs and symptoms.

According to Jackson's thermal wound theory, there are three zones of major burn injury, shaped usually like a bull's-eye.

• Zone of coagulation at the center of the wound, where all tissue is damaged.
• Zone of stasis surrounds the coagulation area, where some tissue is undamaged.
• Zone of hyperemia is the unburned area surrounding the zone of stasis, but it is red due to increased blood flow through inflammatory response.^[3]

Factors

The minimum temperature that can cause a burn in a finite amount of time is 44 °C (111 °F). From 44° to 51 °C (111° to 124 °F), the rate of burn increases by a factor of approximately four with each Celsius degree risen or twice per Fahrenheit degree risen, from six hours down to six seconds. The burn would develop in less than a second if the exposure temperature is at least 70 °C (160 °F).^[3]

Resistance

There are skin factors that offer resistance to burns. A person who is more burn resistant would require higher temperature and longer exposure to burn as badly than a less resistant person.

Thicker skin would offer more insulation from heat. External factors on the skin like hair, moisture or oils can also help ease and delay the burn. Another factor is skin circulation, which is used to dissipate heat imprinted on the skin.^[3]

Causes

Hot liquids and steam

Scalding is a type of thermal burn caused by boiling water and steam, commonly suffered by children. Scalds are commonly caused by accidental spilling of hot liquids, having water temperature too high for baths and showers, steam from boiling water or heated food, or getting splattered by hot cooking oil.^[4] Scalding is usually a first- or second-degree burn, and third-degree burn can sometimes result from prolonged contact.^[5] Nearly three quarters of all burn injuries suffered by young children is scalding.^[6]

Fire

Fire causes about 50% of all cases of thermal burns in the United States.^[7] The most frequent event where people get burned by fire is during house fires encountered by firefighters and trapped occupants,^[8] where 85% of all fire deaths take place.^[9] Fireworks are another notable cause of fire burns, especially by adolescent males on Independence Days.^[6] The most common cause of injury by fire or flame by children is touching candle flame. In some regions, such as the western United States, getting burned by wildfires are common, especially by firefighters who are trying to fight forest fires. Wildfires can suddenly shift due to changing wind directions, making it harder for firefighters and eyewitnesses to avoid getting burned.

If clothing the person wears catches fire, third-degree burn can develop in the matter of just few seconds,^[10] unless if the victim is wearing heavy clothes.

Hot objects

Solid objects that are hot can also cause contact burns, especially by children who intentionally touch things that they are unaware are too hot to touch.^[11] Such burns imprinted on the skin usually form a pattern that resembles the object. Sources of burns from solid objects include ashes and coal, irons, soldering equipment, frying pans and pots, oven containers, light bulbs, and exhaust pipes.^[12]

Prevention

Education is an important tool for children on how to prevent getting burned by fire or getting scalded. In that act, firefighters and community leaders are often employed in schools and clinics.^[9]

Smoke alarms installed in homes are used to reduce deaths resulting from fire by half. Homeowners should change batteries at least once a year and replace smoke alarms every decade. Before fire occurs, a family should practice evacuating home, and when fire occurs the family must leave the residence immediately (within two minutes). To prevent house fires, a family should keep flammable objects, like matches, out of children's reach, and they must not leave anything involving flames unattended while keeping objects that can catch fire away from it by at least 12 inches, like stove ovens, stovetops, space heaters, and candles. Fire extinguishers should be stored in the kitchen, where most house fires start.^[13]

To prevent children from getting burned, water temperature must not be set too high when taking baths or washing hands, nonflammable sleepwear should be worn, backburners should be used when cooking something on the stove, and hot foods, drinks, and irons should be kept away from the edge of counter and table.^[14] Oven mitts and potholders must be used in handling hot containers. People should be careful when taking hot foods out of microwave ovens, and covers should be opened gently to reduce the risk of steam burns.^[15]

Treatment

The household method of treating a minor burn is cooling the burn using cool water or applying antiseptic onto it. The pain or inflammation can effectively be treated using acetaminophen (paracetamol), or ibuprofen. Ice, butter, cream and ointment cannot be used since they can worsen the burn.^[16]

If person is on fire, he/she must be told to stop, drop, and roll, cover them with heavy blanket, wool, coat, or rug. Then water should be poured onto the victim to cool them down. Burned clothing stuck to the skin must not be removed. CPR can be performed and be sent to a hospital if the burn is severe enough.^[16] Severe burn patients are often treated through trauma resuscitation, airway management, fluid resuscitation, blood transfusion, wound management, and skin grafting, as well as the use of antibiotics.^[2][17]

Outcome

For people who are hospitalized for thermal burns, 95% of them survive. Survival rates increased steadily over the last half century due to advances in treating burns as well as more trustful burn centers. According to statistics from 1990 to 1994, the risks of death caused by burns are greater for: people older than 60 years of age, burns covering over 40% of the body, and patients suffering inhalation injury. According to the formula developed by authors, patients who has zero risk criteria would have 99.7% chance of survival, ones who have one criterion would have 97% chance of survival, patients having two would have 67% chance, and patients nursing all three would have 10% chance of survival.^[2]

Epidemiology

In the United States, over two million people required medical attention for thermal burns every year. About 1 in 30 of those victims (75,000) are hospitalized for thermal burns every year, with a third of those patients stay in the hospital for more than two months. About 14,000 Americans die each year from burns.^[18]

Children

Thermal burns are one of the most common mode of early childhood injury.^[11] In the United States, burns are the third most common cause of accidental death among children.^[19] Nearly 96,000 children around the world died as a result of thermal burns in 2004,^[6] and 61,400 died in 2008 from thermal injuries.^[9] Deaths from burns dropped by 55% from 1999 to 2011.^[20] Burns are the only mode of unintentional injury where more girls are suffered from it than boys worldwide, including by fire.^[6]

References

External Links

• Burns at MedlinePlus