Fiser Chapter 17 BURNS Flashcards
1st degree burn
Epidermis (sunburn)
2nd degree burn
Superficial dermis (papillary): Painful to touch, blebs/blisters, hair follicles intact, blanches, do NOT need skin graft
Deep dermis (reticular): decreased sensation, LOSS OF HAIR FOLLICLES, need skin graft
3rd degree burn
Leathery (charred parchment); down to subcutaneous fat
4th degree burn
Down to bone; into adjacent adipose or muscle tissue
Which burns heal?
1st and superficial 2nd degree burns: epithelialization from hair follicles
Complications of burns
Compartment syndrome
Rhabdomyolysis with myoglobinuria
Tx: hydration, alkalinize urine
Who gets admitted to a burn center?
No 1st degree burns
2nd and 3rd degree:
>20% (>10% if <10 or >50)
Or if significant hand/face/feet/genital/perineal/joint skin burns
3rd degree: >5% any age group
Electrical and chemical burns
Concomitant inhalational injury
Mechanical trauma, preexisting medical conditions, patients with special needs, child abuse/neglect
TBSA assessment
Rule of 9s
Head 9 Arms 9 each Chest 18 Back 18 Legs 18 each Perineum 1
Or palm = 1%
Parkland formula
Use for burns >/= 20%
Volume LR = 4 cc/kg x kg x % TBSA
Give 1/2 in first 8 hours, second half in second 16 hours
UOP best measure: goal 0.5-1.0 cc/kg/h in adults, 2-4 cc/kg/h in <6mo
When can Parkland formula grossly underestimate volume requirement?
inhalational injury
EtOH
electrical injury
post-escharatomy
What do you use in burn resuscitation?
LR in first 24 hr
Albumin in first day can cause increased pulmonary complications. Can use after 24hr
Escharotomy indications
- Circumferential deep burns
- Low temp
- Weak pulse
- Decreased capillary refill
- Decreased pain sensation
- Decreased neurological function in extremitiy
- Problems ventilating patient with chest torso burns
Perform within 4-6 hours
Fasciotomy indication in burn patient
If compartment syndrome suspected after escharotomy
Risk factors for burn injuries
EtOH Drugs Age (very young or very old) Smoking Low socioeconomic status Violence Epilepsy
H&P signs that suggest abuse
- Delayed presentation for care
- Conflicting histories
- Previous injuries
- Sharply demarcated margins
- Uniform depth
- Absence of splash marks
- Stocking or glove patterns
- Flexor sparing
- Dorsal location on hands
- Very deep localized contact injury
Child abuse accounts for 15% of burn injuries in children
Lung injury MoA
Carbonaceous materials and smoke (not heat)
Risk factors for airway injury in burn
- EtOH
- Trauma
- Closed space
- Rapid combustion
- Extremes of age
- Delayed extrication
Signs and symptoms of possible airway injury
- Facial burns
- Wheezing
- Carbonaceous sputum
Indications for intubation
- Upper airway stridor or obstruction
- Worsening hypoxemia
- Massive volume resuscitation can worsen symptoms
Most common infection in patients with >30% BSA burns
Pneumonia
Also MCC death after >30% BSA burns
MCC death after 30% BSA burns
Pneumonia
Acid and alkali burns tx
Copious water irrigation
Alkalis produce deeper burns due to liquefaction necrosis
Acid burns produced coagulation necrosis
Hydrofluoric acid burns tx
Calcium
Powder burns tx
Wipe away before irrigation
Tar burns tx
Cool, then wipe away with lipophilic solvent (adhesive remover)
Electrical burns tx and complications
Cardiac monitoring
Monitor for rhabdo and compartment syndrome
Watch for polyneuritis, quadriplegia, transverse myelitis, cataracts, liver necrosis, intestinal perforation, gallbladder perforation, pancreatic necrosis
Lightning burn complication
Cardiopulmonary arrest 2/2 electrical paralysis of brainstem
Caloric need in burns
25 kcal/kg/day + (30 kcal x % burn)
Protein need in burns
1 g/kg/day + (3 g x % burn)
Glucose need in burns
Best source of nonprotein calories in patients with burns
Burn wounds use glucose in an obligatory fashion
Burn wound excision
- Perform AFTER fluid resusc but <72h
- Used for deep 2nd, 3rd, 4th degree burns
- For each burn wound excision, want <1 L blood loss, <20% skin excised, and <2 hr in OR. Patient can otherwise get very sick.
- Viability based on color/texture/punctate bleeding after removal
-Wounds to face, palms, soles, genitals deferred for 1 week
Skin graft contraindications
Positive beta-hemolytic strep or bacteria > 10^5 in culture
Autografts
- Decrease infection, desiccation, protein loss, pain, water loss, heat loss, RBC loss compared to dermal subtitutes
- Donor skin site regenerated from hair follicles and skin edges on STSGs
Imbibition
Osmotic blood supply to skin graft for days 0-3
Neovascularization
Starts day 3
Poor vascularized beds unlikely to support skin grafting
Tendon, bone without periosteum, XRT areas
STSG thickness
12-15 mm (epidermis and part of dermis)
Homograft use
(Allografts from cadaveric skin)
- Can be a good temporizing material, last 2-4 weeks
- Vascularize and are eventually rejected, then must be replaced
Xenografts (porcine)
- Not as good as autografts or homografts
- Last 2 weeks
- Do NOT vascularize
Dermal substitutes
worst
Meshed grafts
-Use for back, flank, trunk, arms, legs
Most common reason for skin graft loss
- Seroma or hematoma
- Need to apply pressure dressing (cotton balls) to skin graft to prevent this
STSG versus FTSG
STSG: more likely to survive, graft not as thick so easier for imbibition and revascularization
FTSG: less wound contraction, good for hands
Burn scar hypopigmentation and irregularities prevention
Dermabrasion thin split-thickness grafts
Face burn care
Topical antibiotics for 11st week
FTSG for unhealed areas (nonmeshed)
Hand burn care
Superficial: ROM exercises, splint in extension if too much edema
Deep: FTSG, immobilize in extension for 7 days after, then PT, may need wire fixation of joints if unstable or open
Palm burn care
Try to preserve specialized palmar attachments
FTSG, then splint hand in extension for 7 days
Genitals burn care
STSG meshed is ok
Burn wound infection prevention
Bacitracin or Neosporin immediately
No role for IV abx ppx
Need 10^5 organisms for infection
Burn wound infection organism
MCC is pseudomonas (burn wound sepsis) > staph, e coli, enterobacter
Candida increased 2/2 topical antimicrobials
HSV most common viral
Burn wound infection risk factors
> 30% BSA
Burn wound infection pathophysiology
Impaired granulocyte chemotaxis and cell-mediated immunity
Silver sulfadiazine side effects
Neutropenia Thrombocytopenia Sulfa allergy reaction Limited eschar penetration Can inhibit epithelialization Ineffective against some pseudomonas (but effective for candida)
Silver nitrate side effects
Electrolyte imbalances Discoloration Limited eschar penetration Ineffective against some pseudomonas and GPCs Methemoglobinemia (in G6PD deficiency)
Mafenide sodium (sulfamylon) characteristics
Painful application
Metabolic acidosis d/t carbonic anhydrase inhibition (decreased renal conversion of H2CO3 -> H2O and CO2)
Good eschar penetration, good for burns overlying cartilage
Broadest spectrum against pseudomonas and GNRs
Mupirocin
Good for MRSA, but very expensive
Signs of burn wound infection
- Peripheral edema
- 2nd to 3rd degree burn conversion
- Hemorrhage into scar
- Erythema gangrenosum
- Green fat
- Black skin around wound
- Rapid eschar separation
- Focal discoloration
Best way to detect burn wound infection (and differentiate from colonization)
Biopsy of burn wound
Complications after burns
- Seizures
- Peripheral neuropathy (small vessel injury and demyelination)
- Ectopia (burned adnexa contraction, tx eyelid release)
- Eye injury (fluorescein stain, tx topical fluoroquinolone or gentamicin)
- Coreneal abrasion (tx topical abx)
- Symblepharon (eyelid stuck to conjunctiva, tx release with glass rod)
- Heterotopic ossification of tendons (tx PT, may need surgery)
- Fractures (Tx external fixation to allow for burn tx)
- Curling’s ulcer
- Marjolin’s ulcer
- Hypertrophic scar
Curling’s ulcer
Gastric ulcer that occurs with burns
Marjolin’s ulcer
Highly malignant squamous cell CA that arises in chronic non-healing burn wounds or unstable scars
Hypertrophic scar
- Usually occurs 3-4 months after injury 2/2 increased neovascularity
- More likely to be deep thermal injuries that take >3 weeks to heal, heal by contraction and epithelial spread, or heal across flexor surfaces
-Tx: steroid injection into lesion (best), silicone, compression; wait 1-2 yr before scar modification surgery
Erythema multiforme
least severe, self-limited, target lesions
SJS
more serious
<10% BSA
TEN
most severe form
Staph scalded skin syndrome
Caused by staphylococcus aureus
Skin epidermal-dermal separation
Seen in EM, SJS, TEN
TEN causes
Dilantin
Bactrim
PCN
Viruses
TEN tx
- Fluid resuscitation
- Supportive
- Prevent wound desiccation with homografts/xenografts wraps
- Topical abx
- IV abx if due to staphylococcus
- NO Steroids
