Burns

Burns

Dr Abhijeet DeshmukhDNB PediatricsFellow in PICU & NICU

50% of burns - pediatric population, 17% - < 5 yearsInfants and children increased susceptibility to death- as they have limited physiologic reserves & the patterns of injury are very different from adults.

Types of Burn Injuries Scald Burns More likely child abuse< 5 years Thorough history should include the type and consistency of the causative liquid. oil and thick soups - higher heat capacity and more viscouscause longer contact at higher temperatures more damagewater of 140 C deep burns in 3 seconds of contact & 160 C - 1 second

Abuse - glove or stocking like, and/or symmetric burns to the buttocks, legs, or perineum. Concomitant fractures and retinal hemorrhages, delays in seeking treatment or inconsistencies in the patient history. full evaluation by social services with referral to appropriate state or government agencies regardless of the depth or extent of burn.

Thermal Burns > 5 years.~ 50% of all burn admissions. flame or contact with hot objects 90% - minor and outpatient management with good outcomes.larger burns - mortality influenced by - size, age , +/-inhalation injury.extent of soft tissue injury duration of exposure , presence and type of clothing material

Electrical Burns Rare (2% - 3%) but devastating Mejority - electrical cords and outlets, Minority - lightening. AC > DCAC -cyclic flow of electricity tetanic contractions increased tissue damage Children propensity to chew on cords or insert objects into outlets.

Wet or moist skin, including the mucous membranes around the mouth, has negligible resistanceconsiderable soft tissue trauma. Nerves, blood vessels, and muscles - least resistance, as compared to bone, fat, and tendons.lack of overt skin damage may mask more significant underlying soft-tissue damage.

Chemical Burns Most common - strong bases in common household products. Alkali drain cleaners (sodium hydroxide) denature cutaneous lipids.Severity - type and concentration & duration of exposure. Initial treatment - copious irrigation with tepid water for > 15 minutes. Never neutralize the acid or base as exothermic reaction worsens tissue injury.

Depth & Extent of Burn injurySuperficial Burns/First degree burns :significant pain, erythematous changes, lack of blistering.Damage to epidermis only, sparing the dermis and dermal structures. blanch on examination & heal within 2 to 3 days after the damaged epidermis desquamates. eg. - sun burns. Scarring is rare

Superficial Partial-Thickness Burns / 2nd degree burnsentire epidermis and superficial dermis. fluid-containing blisters at the dermal-epidermal junction. After debridement, the underlying dermis is erythematous, wet-appearing, painful, and blanches with pressure. deeper dermis is left undamaged - heal within 2 weeks without hypertrophic scarring.No need for skin grafting

Deep Partial-Thickness Burns / 2nd degree burnsclinically similar to third-degree burns. As blood vessels of the dermis are partially damaged blister base - mottled pink and white appearancedo not easily blanch , less painful than superficial burns due to nerve injury. Treatment - excision and grafting. Need surgical intervention,May develop hypertrophic scars and/ or contractures.

Full-Thickness Burns /3rd degree burnscomplete involvement of all skin layers and require definitive surgical management. white, cherry red, brown, or black in color, and do not blanch with pressure. dry and often leathery typically insensate because of superficial nerve injury.

Fourth-degree burns - full-thickness + the underlying subcutaneous fat, muscle, and tendons. May need amputation and/or extensive reconstruction with grafting.

Zones of Injury

Burn wounds continue to evolve for days and the inflammatory process may last for several months. Divided into : 1) zone of coagulation : necrotic tissues closest to the injury site2) zone of stasis : area of ongoing injury, located between the zones of coagulation and hyperemia, Poor perfusion of this zone initially viable tissue in this area to further necrosis and deeper wounds. 3) zone of hyperemia : normal, uninjured skin with a physiologic increase of blood flow in response to local tissue injury.

ManagementEstimating the Extent of the Burn An accurate assessment & Total body surface area (TBSA) of burn minimize morbidity and mortality. Overestimation cause over resuscitation with resultant complications, inappropriate transfer to burn centers, Newer methods for (TBSA) are being researched -computerized imaging, two- and three-dimensional graphics, and body contour reproductions.

Current methods for (TBSA)1) Adults : rule of nines, by Palaski and Tennison (palm and fingers of one hand account for 1% of the normal body surface area). This calculation often overestimates, especially in children.BSA is distributed differently in children and infants due to proportionally larger heads and smaller extremities.

2) Infants & Children : Lund Browder diagram

Early Management of Burn Injuries After removing or extinguishing the source washed with tepid water. Chemical burns - flushed copiously to remove the inciting agent and prevent further tissue damage. Ice or iced water- increase tissue damage , hypothermia & mortality, in patients with more extensive burns.Approximately 10% of all burn patients present with additional traumatic injuries severe burn shock or trauma loss of airway due to altered mental status or supraglottic obstruction from edema formation.

Signs of inhalation injury : facial burns, singed nasal hairs, carbonaceous sputum, hypoxia, and history of entrapment in an enclosed space. Evaluation of circulation and resuscitation in greater than 10% TBSA because these injuries are characterized by a systemic inflammatory response that may lead to hemodynamic lability.Electrical injuries compartment syndromes , multiorgan system involvement, Cardiac dysrhythmias , direct muscle necrosis , Seizures and spinal cord transections & respiratory arrest secondary to injury of the brainstem or tetany of the respiratory musculature.

The majority of these burns can safely be treated with minor debridement, oral hydration, topical wound care, and outpatient follow-up. Those patients requiring supplemental nutrition or hydration, or who fail outpatient treatment, may need continued care in an inpatient setting if there is a suspicion for inhalation injury, inpatient treatment with intravenous resuscitation and potential transfer to a burn center should be considered.

Before transfer : -wounds covered with clean, dry material or nonadherent gauze.wet dressings - avoided to prevent hypothermia and subsequent complications in patients with large burn wounds. Tetanus prophylaxis with appropriate pain control before transport. In extensive burns, a Foley catheter should be inserted to help guide fluid management.

Resuscitation General Principles>10% total BSA - IV fluid resuscitation & urinary catheter. In major injury - nasogastric tube to decompress the stomach. During transport - maintain body temperature.

Fluid ResuscitationBurn leads to intravascular volume depletion Major losses occur during the first 24 hrs crystalloids used. Myocardial depression - 24-36 hrs after injury. The goal of resuscitation is to maintain adequate intravascular volume to support tissue perfusion and thereby preserve organ function. The adequacy of resuscitation - based on observation of blood pressure, heart rate, and urine output. Fluid to maintain normal blood pressure, heart rate, and hourly urine output of 1 mL/kg/hr in the infant and young child and 0.5 mL/kg/hr in the child >12 years of age or >50 kg in weight.

Parkland formula - crystalloid-based formula - with RL - based on the BSA of burn and the patient's body weight. Maintenance fluids (5% dextrose in lactated Ringer solution) = (4ml/kg+ BSA of burn) + Maintainance fluids(For adults and children who weigh >40 kg, maintenance fluids are not included in the estimate of fluid requirements.) Half of this - in the first 8 hrs after injury, and other half is given in the following 16 hrs.

After the first 24 hrs, - maintenance requirements + to replace ongoing losses. The hourly evaporative fluid loss from wounds can be estimated as: = ( 25 + Burn surface area) x total BSAThe evaporative losses are primarily free water. However, to avoid rapid changes in sodium concentration in children, this loss is replaced with - 5% dextrose in 0.2% normal saline. loss of serum protein occurs in > 40% BSA burns. When the injury is larger, the loss is replaced in the second 24 hrs after injury with 5% albumin.

ultimate goal to maintain normal blood pressure, heart rate, urine output, and serum sodium

Hypoalbuminemia- Causes : Increased losses of albumin : d/t drainage from burn wounds, and inflammatory mediators triggered capillary leakageReduced Albumin production in critical illness due to an increase in the production of acute phase proteins. Dilutional hypoalbuminemia in the immediate postresuscitation phase d/t increased intravascular vol.Albumin is given - to avoid exacerbating acute lung injury, diarrhea, feeding intolerance, impaired wound healing, and the resultant complications.

in critically ill patients- 25% albumin should be added if the serum level is below 3 mg/dL.

Management of Inhalation Injury : aggressive pulmonary toilet, mucolytics, early identification and treatment of infection and supportive care. nebulized heparin to reduce atelectasis and improved pulmonary function, Prophylactic antibiotics & corticosteroids are not usedsupplemental oxygen & advanced modes of assisted ventilation and hyperbaric oxygen therapy. Stridor - racemic epinephrine neb

12% - require intubation70% of those intubated have sustained inhalation injury .

Wound Care

General PrinciplesObjective - to avoid infection and protect the wound from further injury. Small (