Burn depth difficult to determine with the naked eye

January 10, 2017

Visual assessment of a burn injury is insufficient to judge the depth of a burn; hypertrophic scars left by burn injuries are increasingly being treated with lasers with impressive results.

Clinicians should not attempt to estimate the depth of a burn injury using only clinical judgment because that judgment may be incorrect, says the Medical Director of the Burn Program at the Hospital for Sick Children in Toronto, Canada, speaking at the annual meeting of the Canadian Association of Wound Care (CAWC) about burn injuries and burn scars.

"Keep in mind that emergency room clinical accuracy is only 30% among expert staff," says Joel Fish M.D., F.R.C.S.C., a plastic surgeon. "Burn depth is diagnosed incorrectly in emergency rooms because of a lack of understanding of the pathophysiology of burns. You cannot say a burn injury does not look too bad because you really don't know."

The pathophysiology of a burn involves hyperaemia, coagulation, and stasis, and the clinical appearance may be misleading in terms of representing the severity of the burn injury. Indeed, the appearance of a burn can change drastically in the first 48 to 72 hours after a burn is sustained.

"The ultimate depth of the wound can take more than two weeks until it is certain," Dr. Fish says.

The depth of the problem

Near-infrared spectroscopy (NIR) has been shown to be effective in classifying burn injuries. A study involving 16 patients with acute superficial and full-thickness burns showed that the use of NIR was able to differentiate between superficial and full-thickness burn injuries.1

NIR is available commercially in Canada through the Multispectral MOBile tiSsue Assessment device, referred to as MIMOSA. The device is a non-invasive technology that can photograph wounds using near-infrared light that, apart from classifying burn injuries, can also be used to predict when a diabetic foot ulcer will develop before it is apparent to the human eye.

For the time being, ERs will continue to rely on visual assessment in daily clinical practice to evaluate burn depth, and that assessment will not offer a high degree of accuracy.

"What is perceived as (a) minor (burn) is often not,” Dr. Fish says, “especially taking into consideration the point of view of parents (of a child). Even contact with a hot latte drink for two seconds can result in a full-thickness burn.

NEXT: Children and burns

 

 

Children and burns

Clinicians need to take the time to get a complete history to identify any burns in children that have been a result of neglect or abuse.

"It is a question of whether the clinical characteristics of the burn wound fit the story," says Dr. Fish. "You should note if the clinical characteristics do not fit the story."

Fortunately, the vast majority of burns that are seen in the pediatric setting are minor.

"Major burns in children are a rarity," Dr. Fish says. Most of the burns that children do experience are the result of contact with scalding hot liquids or hot surfaces.

"Children are a bundle of curiosity under the age of five and they are attracted to things that glow or give off heat," explains Dr. Fish. "The most common locations for the injuries are in the bathroom and the kitchen."

Dr. Fish also stresses that there is "a lot of room in pediatric burns for prevention," and he notes an ongoing issue of glass-fronted, gas fireplaces as a particular risk to children under age two. Data from both the U.S. and Canada demonstrate that young children sustain burn injuries from contact with the glass front of the fireplaces, and that these injuries can be severe.

The American Burn Association Prevention Committee has been involved in an active campaign to increase public awareness about glass-fronted fireplaces and pediatric burns.2

"Industry has not taken an interest in this issue," notes Dr. Fish.  

Burns in adults

In terms of the management of burns in the adult setting, Karen Cross M.D., Ph.D., F.R.C.S.C., a surgeon in the division of plastic and reconstructive surgery at St. Michael's Hospital in Toronto and co-chair of the CAWC 2016 conference, says that advanced dressings do not need to be routinely applied to burn injuries in the early triage period, particularly if patients will be referred to a burn specialist for treatment.

Dr. Cross"If a patient will be seen in a couple of days, you can apply an ointment like Polysporin™ and a non-stick dressing (to the burn)," says Dr. Cross in a recent talk with Dermatology Times. "There is a shift away from using silver sulfadiazine cream (Flamazine™) in the treatment of burns to advanced silver dressings that can stay in place for longer than 24 hours. This is appropriate as well for patients who may be treated as outpatients and utilizing home care services."

Larger burns, those affecting more than 10 per cent of total body surface area, should be referred for management to a burn center, according to Dr. Cross, citing criteria from the American Burn Association.

"These burns require multidisciplinary care in order to optimize morbidity and mortality," says Dr. Cross.

Lasers remedy scarring

A major advance in the treatment of hypertrophic scars that develop as a result of burns has been the use of fractional lasers, which are of benefit in both the adult and pediatric settings.

"Lasers are novel in treating scars," Dr. Cross explains. "They are an alternative to using steroid injections, silicone sheets, pressure and other topical therapies."

The use of ablative carbon dioxide fractional lasers has resulted in clinical and histologic changes in burn scars, with new collagen fibers forming in the upper dermis as a result of the treatment.3 Another investigation demonstrated decreases in the Vancouver Scar Scale with the use of photothermolysis to treat hypertrophic scarring subsequent to burn injuries.4

In combination, lasers with non-invasive techniques can replace the need for further surgery, according to Dr. Cross.

"These technologies, however, are not available frequently to patients as they are considered cosmetic procedures which means out-of-pocket pay for the patient," says Dr. Cross.          

Currently, the Hospital for Sick Children has the largest pediatric burn laser program in Canada and has treated more than 150 patients, Dr. Fish reports.

"Objective data have shown great improvements in itch, softness and thickness of the scars," Dr. Fish says. "Lasers have added a valuable instrument for treating burn/traumatic scars and will undoubtedly change the way we treat burns in children during the acute phase as we now have the ability to modulate the scar effectively and in some cases eliminate the need for grafting."

Disclosure:

Dr. Fish has no relevant disclosures.

Dr. Cross is the CEO and Co-Founder of Mimosa Diagnostics in Toronto

 

References:

1Cross KM, Leonardi L, Payette JR, et al. Clinical utilization of near-infrared spectroscopy devices for burn depth assessment. Wound Repair Regen. 2007;15(3):332-40.

2Toor J, Crain J, Kelly C, Verchere C, Fish J. Pediatric Burns from Glass-Fronted Fireplaces in Canada: A Growing Issue Over the Past 20 Years. J Burn Care Res. 2016;37(5):e483-8.

3Lee SJ, Suh DH, Lee JM, Song KY, Ryu HJ. Dermal Remodeling of Burn Scar by Fractional CO2 Laser. Aesthetic Plast Surg. 2016;40(5):761-8.

4Khandelwal A, Yelvington M, Tang X, Brown S. Ablative fractional photothermolysis for the treatment of hypertrophic burn scars in adult and pediatric patients: a single surgeon's experience. J Burn Care Res.      2014;35(5):455-63.