Burns

Question 1

Classification of burns

Answer 1

• Superficial
  
  • Erythema
  • Painful
  • i.e. sunburn
• Partial thickness
  
  • Heal within 2-3 weeks if not complicated
  • Superficial
    
    • No loss of dermis
    • Painful
    • Blisters
  • Deep
    
    • Loss of dermis but adnexae remain
    • Healing from adnexae (i.e. follicles)
    • Very painful
• Full thickness
  
  • Complete loss of dermis
  • Charred, waxy, white skin
  • Anaesthetic
  • Heal from the edges - scarring

Question 2

Complications of burns

Answer 2

• Early
  
  • Infection (loss of barrier function, necrotic tissue, SIRS)
  • Hypovolaemia (loss of fluid in skin, increased capilliary permeability)
  • Metabolic disturbance (↑K, ↑myoglobin, ↑Hb leads to AKI)
  • Compartment syndrome (circumferential burns)
  • Peptic ulcers (Curling’s ulcers)
  • Pulmonary (CO poisoning, ARDS)
• Intermediate
  
  • VTE
  • Pressure sores
• Late
  
  • Scarring
  • Contractures
  • Psychological problems

Question 3

Wallace rule of 9s (% BSA burnt)

Answer 3

• Head and neck - 9%
• Arms - 9% each
• Torso - 36% including front and back
• Legs -18% each
• Perineum - 1%
• Palm - 1%

NB - Can also use Lund and Browder charts

Question 4

Management of burns

Answer 4

• Airway
  
  • Examine for respiratory burns
    
    • Soot in oral or nasal cavity
    • Burnt nasal hairs
    • Hoarse voice, stridor
  • Flexible laryngoscopy can be helpful
  • Consider early intubation + dexamethasone (↓ inflammation)
• Breathing
  
  • 100% O2
  • Exclude constricting burns
  • Signs of CO poisoning
    
    • Headache
    • N/V
    • Confusion
    • Cherry red appearance
  • ABG
    
    • COHb level
    • SpO2 unreliable if CO poisoning
• Circulation
  
  • Fluid losses may be huge
  • 2x large-bore cannulae in each ACF
  • Bloods: FBC, U+E, G+S/XM
  • Start 2L warmed Hartmann’s immediately

Question 5

Replacement of fluids

Answer 5

• Parkland Formula to guide replacement in 1st 24hrs
  
  • 4 x wt. (kg) x % burn = mL of Hartmann’s in 24h
  • Replace fluid from time of burn
  • Give half in 1st 8h
  • Best guide is UO: 30-50mL/h
• Muir and Barclay Formula to guide fluid replacement
  
  • (wt. x % burn)/2 = mL of Colloid per unit time
  • Time units: 4, 4, 4, 6, 6, 12 = 36hrs total
  • May need to use blood

Question 6

Treatment of burns

Answer 6

• Analgesia - morphine
• Dress partial thickness burns
  
  • Biological (i.e. cadaveric skin)
  • Synthetic
  • Cream (i.e. Flamazine + sterile film)
• Full thickness burns
  
  • Tangential ecision debridement
  • Split-thickness skin grafts
• Circumferential burns may require escharotomy to prevent compartment syndrome
• Anti-tetanus toxoid
• Consider prophylactic antibiotics