burn on a single examination and repeated examinations over a few days may be necessary. in those who have a headache or are dizzy and have a fire-related burn, carbon monoxide poisoning should be considered. cyanide poisoning should also be considered. size burn severity is determined through, among other things, the size of the skin affected. the image shows the makeup of different body parts, to help assess burn size. the size of a burn is measured as a percentage of total body surface area (tbsa) affected by partial thickness or full thickness burns. first-degree burns that are only red in color and are not blistering are not included in this estimation. most burns (70%) involve less than 10% of the tbsa. there are a number of methods to determine the tbsa, including the wallace rule of nines, lund and browder chart, and estimations based on a person's palm size. the rule of nines is easy to remember but only accurate in people over 16 years of age. more accurate estimates can be made using lund and browder charts, which take into account the different proportions of body parts in adults and children. the size of a person's handprint (including the palm and fingers) is approximately 1% of their tbsa. severity american burn association severity classification minormoderatemajor adult <10% tbsaadult 10–20% tbsaadult >20% tbsa young or old < 5% tbsayoung or old 5–10% tbsayoung or old >10% tbsa <2% full thickness burn2–5% full thickness burn>5% full thickness burn high voltage injuryhigh voltage burn possible inhalation injuryknown inhalation injury circumferential burnsignificant burn to face, joints, hands, or feet other health problemsassociated injuries to determine the need for referral to a specialized burn unit, the american burn association devised a classification system. under this system, burns can be classified as major, moderate, and minor. this is assessed based on a number of factors, including total body surface area affected, the involvement of specific anatomical zones, the age of the person, and associated injuries. minor burns can typically be managed at home, moderate burns are often managed in a hospital, and major burns are managed by a burn center. severe burn injury represents one of the most devastating forms of trauma. despite improvements in burn care, patients can be left to suffer for as many as three years post-injury. signs of smoke inhalation signs of smoke inhalation includes hoarse voice, dyspnea, facial burns, singed nasal hairs, sputum which contains carbonaceous materials, stridor and wheezing may be present in later stages. prevention historically, about half of all burns were deemed preventable. burn prevention programs have significantly decreased rates of serious burns. preventive measures include: limiting hot water temperatures, smoke alarms, sprinkler systems, proper construction of buildings, and fire-resistant clothing. experts recommend setting water heaters below 48.8 °c (119.8 °f). other measures to prevent scalds include using a thermometer to measure bath water temperatures, and splash guards on stoves. while the effect of the regulation of fireworks is unclear, there is tentative evidence of benefit with recommendations including the limitation of the sale of fireworks to children. management resuscitation begins with the assessment and stabilization of the person's airway, breathing and circulation. if inhalation injury is suspected, early intubation may be required. this is followed by care of the burn wound itself. people with extensive burns may be wrapped in clean sheets until they arrive at a hospital. as burn wounds are prone to infection, a tetanus booster shot should be given if an individual has not been immunized within the last five years. in the united states, 95% of burns that present to the emergency department are treated and discharged; 5% require hospital admission. with major burns, early feeding is important. protein intake should also be increased, and trace elements and vitamins are often required. hyperbaric oxygenation may be useful in addition to traditional treatments. intravenous fluids in those with poor tissue perfusion, boluses of isotonic crystalloid solution should be given. in children with more than 10–20% tbsa (total body surface area) burns, and adults with more than 15% tbsa burns, formal fluid resuscitation and monitoring should follow. this should be begun pre-hospital if possible in those with burns greater than 25% tbsa. the parkland formula can help determine the volume of intravenous fluids required over the first 24 hours. the formula is based on the affected individual's tbsa and weight. half of the fluid is administered over the first 8 hours, and the remainder over the following 16 hours. the time is calculated from when the burn occurred, and not from the time that fluid resuscitation began. children require additional maintenance fluid that includes glucose. additionally, those with inhalation injuries require more fluid. while inadequate fluid resuscitation may cause problems, over-resuscitation can also be detrimental. the formulas are only a guide, with infusions ideally tailored to a urinary output of >30 ml/h in adults or >1ml/kg in children and mean arterial pressure greater than 60 mmhg. while lactated ringer's solution is often used, there is no evidence that it is superior to normal saline. crystalloid fluids appear just as good as colloid fluids, and as colloids are more expensive they are not recommended. blood transfusions are rarely required. they are typically only recommended when the hemoglobin level falls below 60-80 g/l (6-8 g/dl) due to the associated risk of complications. intravenous catheters may be placed through burned skin if needed or intraosseous infusions may be used. wound care early cooling (within 30 minutes of the burn) reduces burn depth and pain, but care must be taken as over-cooling can result in hypothermia. it should be performed with cool water 10–25 °c (50.0–77.0 °f) and not ice water as the latter can cause further injury. chemical burns may require extensive irrigation. cleaning with soap and water, removal of dead tissue, and application of dressings are important aspects of wound care. if intact blisters are present, it is not clear what should be done with them. some tentative evidence supports leaving them intact. second-degree burns should be re-evaluated after two days. in the management of first and second-degree burns, little quality evidence exists to determine which dressing type to use. it is reasonable to manage first-degree burns without dressings. while topical antibiotics are often recommended, there is little evidence to support their use. silver sulfadiazine (a type of antibiotic) is not recommended as it potentially prolongs healing time. there is insufficient evidence to support the use of dressings containing silver or negative-pressure wound therapy. silver sulfadiazine does not appear to differ from silver containing foam dressings with respect to healing. medications burns can be very painful and a number of different options may be used for pain management. these include simple analgesics (such as ibuprofen and acetaminophen) and opioids such as morphine. benzodiazepines may be used in addition to analgesics to help with anxiety. during the healing process, antihistamines, massage, or transcutaneous nerve stimulation may be used to aid with itching. antihistamines, however, are only effective for this purpose in 20% of people. there is tentative evidence supporting the use of gabapentin and its use may be reasonable in those who do not improve with antihistamines. intravenous lidocaine requires more study before it can be recommended for pain. intravenous antibiotics are recommended before surgery for those with extensive burns (>60% tbsa). as of 2008, guidelines do not recommend their general use due to concerns regarding antibiotic resistance and the increased risk of fungal infections. tentative evidence, however, shows that they may improve survival rates in those with large and severe burns. erythropoietin has not been found effective to prevent or treat anemia in burn cases. in burns caused by hydrofluoric acid, calcium gluconate is a specific antidote and may be used intravenously and/or topically. recombinant human growth hormone (rhgh) in those with burns that involve more than 40% of their body appears to speed healing without affecting the risk of death. the use of steroids is of unclear evidence. allogeneic cultured keratinocytes and dermal fibroblasts in murine collagen (stratagraft) was approved for medical use in the united states in june 2021. surgery wounds requiring surgical closure with skin grafts or flaps (typically anything more than a small full thickness burn) should be dealt with as early as possible. circumferential burns of the limbs or chest may need urgent surgical release of the skin, known as an escharotomy. this is done to treat or prevent problems with distal circulation, or ventilation. it is uncertain if it is useful for neck or digit burns. fasciotomies may be required for electrical burns. skin grafts can involve temporary skin substitutes, derived from animal (human donor or pig) skin or synthesized. they are used to cover the wound as a dressing, preventing infection and fluid loss, but will eventually need to be removed. alternatively, human skin can be treated to be left on permanently without rejection. there is no evidence that the use of copper sulphate to visualise phosphorus particles for removal can help with wound healing due to phosphorus burns. meanwhile, absorption of copper sulphate into the blood circulation can be harmful. alternative medicine honey has been used since ancient times to aid wound healing and may be beneficial in first- and second-degree burns. there is moderate evidence that honey helps heal partial thickness burns. the evidence for aloe vera is of poor quality. while it might be beneficial in reducing pain, and a review from 2007 found tentative evidence of improved healing times, a subsequent review from 2012 did not find improved healing over silver sulfadiazine. there were only three randomized controlled trials for the use of plants for burns, two for aloe vera and one for oatmeal. there is little evidence that vitamin e helps with keloids or scarring. butter is not recommended. in low income countries, burns are treated up to one-third of the time with traditional medicine, which may include applications of eggs, mud, leaves or cow dung. surgical management is limited in some cases due to insufficient financial resources and availability. there are a number of other methods that may be used in addition to medications to reduce procedural pain and anxiety including: virtual reality therapy, hypnosis, and behavioral approaches such as distraction techniques. patient support burn patients require support and care – both physiological and psychological. respiratory failure, sepsis, and multi-organ system failure are common in hospitalized burn patients. to prevent hypothermia and maintain normal body temperature, burn patients with over 20% of burn injuries should be kept in an environment with the temperature at or above 30 degree celsius. metabolism in burn patients proceeds at a higher than normal speed due to the whole-body process and rapid fatty acid substrate cycles, which can be countered with an adequate supply of energy, nutrients, and antioxidants. enteral feeding a day after resuscitation is required to reduce risk of infection, recovery time, non-infectious complications, hospital stay, long-term damage, and mortality. controlling blood glucose levels can have an impact on liver function and survival. risk of thromboembolism is high and acute respiratory distress syndrome (ards) that does not resolve with maximal ventilator use is also a common complication. scars are long-term after-effects of a burn injury. psychological support is required to cope with the aftermath of a fire accident, while to prevent scars and long-term damage to the skin and other body structures consulting with burn specialists, preventing infections, consuming nutritious foods, early and aggressive rehabilitation, and using compressive clothing are recommended. prognosis prognosis in the usa tbsamortality 0–9%0.6% 10–19%2.9% 20–29%8.6% 30–39%16% 40–49%25% 50–59%37% 60–69%43% 70–79%57% 80–89%73% 90–100%85% inhalation23% the prognosis is worse in those with larger burns, those who are older, and females. the presence of a smoke inhalation injury, other significant injuries such as long bone fractures, and serious co-morbidities (e.g. heart disease, diabetes, psychiatric illness, and suicidal intent) also influence prognosis. on average, of those admitted to the united states burn centers, 4% die, with the outcome for individuals dependent on the extent of the burn injury. for example, admittees with burn areas less than 10% tbsa had a mortality rate of less than 1%, while admittees with over 90% tbsa had a mortality rate of 85%. in afghanistan, people with more than 60% tbsa burns rarely survive. the baux score has historically been used to determine prognosis of major burns.