Burns

Reviewed and revised 2 September 2014

OVERVIEW

Burns are injuries to tissues caused by heat, friction, electricity, radiation, or chemicals

• Burn injury is characterised by a hypermetabolic response with physiologic, catabolic and immune effects
• extent of burns and fluid resuscitation is often over-estimated in the ED

EPIDEMIOLOGY

• In adults the usual mechanism is exposure to fire, in child scalding is most common
• maybe associated with alcohol, abuse, epilepsy or psychiatric problem
• mortality is related to age (>50yrs), TBSA (40%) burnt and burn depth
• increased mortality if post-burn resuscitation is delayed >2h

CLASSIFICATION OF BURNS

• Superficial – epidermis only
• Partial – superficial (epidermis and upper layer of dermis), deep (extends to deeper layer of dermis)
• Full – all layers of dermis and may involve underlying tissue

ASSESSING EXTENT OF BURNS

Methods

• Rules of 9’s
• Palm of patient = 1% TBSA burn
• Lund-Browder Chart

OTHER IMPORTANT ASPECTS

• Resuscitation – airway patency, breathing, circulation, LOC
• Adequacy of resuscitation to date – HR, BP, urine output, fluid received
• Associated trauma
• Airway burn or inhalational injury – stridor, burns to face, nose and mouth, carbonaceous sputum
• Facial and/or corneal burns, perineal burns
• Circumferential burns – extremities -> compartment syndrome, ventilator inadequacy -> escharotomy
• Rhabdomyolysis
• Inhalation of toxic gases – CO
• Temperature
• Adequacy of analgesia
• Problems with vascular access
• Evidence of drug/alcohol ingestion
• Co-morbid conditions

MANAGEMENT

Key points

• EMST/ATLS protocol – primary and secondary survey
• Burn assessment and management – debridement by 48 hours
• Transfer to definitive care facility

PRIMARY SURVEY

Airway with C-spine control

• may need ETT urgently (use an uncut tube + wire to maxilla)
• warning signs include = singed nasal hairs, horse voice, productive brassy cough, soot in sputum, stridor, facial burns, breathed fire, voice change
• maximum wound oedema takes place at 12-36hrs after injury
• FOB or nasoendoscopy
• Bronchoscopy – soot, charring, mucosal erythema, necrosis, airway oedema
• RSI
• sux ok for 24-48h then none for 2 days -> 2 yrs
• may need AFOI or surgical airway

Breathing with O2

• 15L/min + reservior bag
• may require ETT + IPPV because of other injuries, major resusication, sedation, ARDS & analgesia, decreased pulmonary compliance
• protective lung injury
• NAC & heparin nebulisers used in some centers
• suction

Circulation with haemorrhage control

• >25% -> SIRS with oedema
• IV access through intact skin where possible
• IVF for >15% in adults & >10% in children
• Hartmans is preferred
• x-match units
• may have to stop surgery to catch up
• aim for PCV 0.3

Disability with assessment of neurological function

• CHI
• CO poisoning
• ETOH poisoning
• analgesia

Exposure with temperature control

• remove all clothes
• if stuck to patient, cut around adherent areas
• keep warm
• assess %TBSA and depth
• warm theatre (32 C)
• humidify (70-80%)

SECONDARY SURVEY

• cool with running cold water (20min)
• bronchoscopy for evidence of an inhalational injury (nebulized heparin and NAC)
• watch for hypothermia
• cover with clingfilm (limits evaporation, heats loss & pain)
• IV morphine
• escharotomy – limbs & chest wall
• have lots of blood ready
• watch for COHb -> will need 100% O2 or hyperbaric O2

ICU MANAGEMENT

Fluid replacement

• required in adult > 15%, children >10%
• Modified Parklands Formula (original Parkland’s formula included colloids)

-> Adults – 4mL/kg/%
-> Children – 3-4mL/kg/%

• give 1/2 in first 8h since the time of injury
• give 1/2 in next 16h
• + maintenance fluid for children <30 kg

• aim for urine output of 0.5mL/kg/hr and normal cardiovascular parameters (HR, BP)
• then albumin after first 24 hours (keep albumin > 20)
• more fluid is typically required if: inhalational injury, electrical burns or delayed resuscitation
• permissive hypovolaemia with non-invasive haemodynamic monitoring is a promising approach
• test for myoglobinuria -> if +ve then rhabdomyolysis is present:

(1) aim 2-3mL/kg/hr
(2) consider: alkalinise urine with 25mmol of HCO3- for each litre of Hartmans
(3) consider: promote diuresis with 12.5g mannitol to each litre of Hartmans

Dressings

• biobrane: superficial
• acticoat: partial
• subcut infusions: hypertonic saline + acetic acid (anti-pseudomonal)

Other issues

• NJ tube -> feed
• strict asepsis
• vigilance for nosocomial infections: line changes every 7 days
• tetanus
• antibiotics in initial period if dirty (frequently cooled at scene with dirty water)
• family discussion
• prognosis: age + TBSA burn should be less than 100.
• monitor for post burn leukopenia (cease silver sulfadiazine and use mafenide acetate, stop cimetidine, consider G-CSF if doesn’t improve in 3 days)

Chemical Burns

• protect self with gloves, apron & facemask
• remove contaminated clothing
• neutralize or dilute with H2O (1hr)

• Hydrofluoric acid – topical calcium gluconate burn gel + Biers block with 10-15mL of 10% calcium gluconate + 5000U of heparin in 40mL 5 % dextrose
• Phosphorus – copper sulphate solution
• Bitumen – cool with H2O, remove with vegetable or paraffin oil

Electrical Burns

• low voltage (<1000V) -> local contact burn
• high voltage (>1000V) -> entrance & exit wound -> may require fasciotomy
  -> side flash = nearby lightening strike -> superficial burns, entry & exit burns +/- respiratory arrest
• direct lightning strike -> often fatal

INDICATIONS FOR REFERRAL TO BURNS CENTRE

Early discussion with your regional burns centre is advised if there is any doubt/concern regarding the management of any burns patient.

• Burns > 10 % TBSA in an Adult
• Burns > 5 % TBSA in a Child
• Full thickness burns > 5% TBSA
• Burns of face, hands, feet, perineum, genitalia, and major joints
• Circumferential burns
• Chemical or electrical burns
• Burns in the presence of major trauma or significant co-morbidity
• Burns in the very young patient, or the elderly patient
• Burns in a pregnant patient
• Suspicion of Non-Accidental Injury

FLUID CREEP

• excess fluid loading is also termed ‘fluid creep’
• fluid creep is common in burns patients
• possible reasons for fluid creep:
  • inaccurate fluid requirement calculations
  • lack of vigilance in reducing unnecessary fluid infusions
  • increased use of sedation and analgesic agents
  • excess crystalloid over colloid replacement
  • inappropriate use of parameters for monitoring adequacy of fluid replacement

References and links

LITFL

• Trauma Tribulation 032 – Trauma! Major Burns
• Toxicology Conundrum 038 — Smoke inhalation with Carbon Monoxide and Cyanide Toxicity
• Trauma Tribulation 005 — Escharotomy

Journals and Textbooks

• Benson A, Dickson WA, Boyce DE. Burns. BMJ. 2006 Mar 18;332(7542):649-52. Review. Erratum in: BMJ. 2006 Apr 1;332(7544):755. PMID: 16543335; PMCID: PMC1403274.
• Coban YK. Infection control in severely burned patients. World J Crit Care Med. 2012 Aug 4;1(4):94-101. PMC3953869.
• Hall KL, Shahrokhi S, Jeschke MG. Enteral nutrition support in burn care: a review of current recommendations as instituted in the Ross Tilley Burn Centre. Nutrients. 2012 Oct 29;4(11):1554-65. PMC3509506.
• Hettiaratchy S, Dziewulski P. ABC of burns: pathophysiology and types of burns. BMJ. 2004 Jun 12;328(7453):1427-9. Review. Erratum in: BMJ. 2004 Jul 17;329(7458):148. PMC421790.
• Norman AT, Judkins KC. Pain in the patient with burns. Contin Educ Anaesth Crit Care Pain 2004;4(2):57-61 [Free Full Text]
• Peck M. Respiratory burn injuries: An overview. Indian J Burns [serial online] 2013 [cited 2014 Sep 2];21:17-23. Available from: http://www.ijburns.com/text.asp?2013/21/1/17/121876
• Snell JA, Loh NH, Mahambrey T, Shokrollahi K. Clinical review: the critical care management of the burn patient. Crit Care. 2013 Oct 7;17(5):241. PMC4057496.
• Williams FN, Branski LK, Jeschke MG, Herndon DN. What, how, and how much should patients with burns be fed? Surg Clin North Am. 2011 Jun;91(3):609-29. PMC3255093.

FOAM and web resources

• DirtMed — Burn Resuscitation Part 1 and Part 2 (2012)
• ICN — Burns and Fluids by Lewis Macken (smaccGOLD, 2014)
• ICU Rounds Podcast 12 — Burns: Fluid Creep (2007)
• ICU Rounds Podcast 28 — Pediatric Burns (2008)
• Maryland CCP — N-acetylcysteine for Inhalational Burn Injury (2014)
• Maryland CCP — Managing the Burn Patient in the ICU (2013)
• Victoria Burn Management Guidelines (a comprehensive resource covering all aspects of burns assessment and management and a great place to download Burns Surface Area charts and Information Posters for clinical areas)