Burns Flashcards
1st degree
sunburn (epidermis)
2nd degree
superficial dermis (papillary): painful to touch; blebs and blisters; hair follicles intact; blanches deep dermis (reticular): decreased sensation; loss of hair follicles (need skin grafts)
3rd degree
leathery feeling (charred parchment); down to subcutaneous fat
4th degree
down to bone, into adjacent adipose or muscle tissue
Scald burns
most common
Body surface burned
head 9 arms 18 (9 and 9) chest 18 back 18 legs 36 (18 and 18) palm = 1%
Parkland formula
give 4cc/kg x % burn in first 24 hours; give 1/2 in first 8 hours
use LR in first 24 hours
*can grossly underestimate volume requirements with inhalational injury, ETOH, electrical injury, postescharotomy
Escharotomy
perform within 4-6 hours
- circumferential burns
- low temperature; weak pulse; decrease cap refill, decrease pain sensation, and decrease neurologic function in extremity; may need fasciotomy if compartment syndrome suspected
child abuse
accounts for 15% of burn injuries in children
Lung injury
caused by carbonaceous materials and smoke, not heat
*risk factors for airway injury - ETOH, trauma, closed space, rapid combustion, extremes of age, delayed extrication
Pneumonia
most common infection in burn wound patients; also most common cause of death after inhalation injury
Acid and alkali burns
copious water irrigation
- alkalis produce deeper burns than acid due to liquefaction necrosis
- acid burns produce coagulation necrosis
Hydrofluoric acid burns
spread calcium on wound
Powder burns
wipe away before irrigation
Tar burns
cool, then wipe away with lipophilic solvent
Electrical burns
caridac monitoring
*can cause rhabdomyolysis and compartment syndrome
Lightning
cardiopulmonary arrest secondary to electrical paralysis of brainstem
1st week - early excision of burned areas
try to excise burn wounds in < 72 hours
*skin grafts are contraindicated if culture is positive for beta-hemolytic strep or bacteria > 10^5
Cardiac output 1st week
first have decrease CO for 24-48 hours then have increase CO (ebb and flow phases following burn)
Burn caloric needs
25 kcal/kg/day + (30 x % burn)
Burn protein need
1 g / kg / day + (3 g x % burn)
Glucose in burn patients
best source of nonprotein calories in patients with burns; burn wounds use glucose in an obligatory fashion
Autografts
best; full thickness or split thickness grafts (should be 12-15 mm, include epidermis and part of dermis); decrease infection, desiccation, protein loss, pain, water loss, heat loss, and RBC loss; increase granulation tissue and improve survival
Homografts
allografts; cadaveric skin; not as good as autografts; can be good temporizing material; last 2-4 weeks; allografts vascularize and are eventually rejected at which time they must be replaced
xenografts
porcine; not as good as homografts; last 2 weeks; these do not vascularize
wounds to face, palms, soles, genitals
deferred for 1st week
most common reason for skin graft loss
seroma or hematoma formation under graft
*need to apply pressure dressing (cotton balls)
STSGs
more likely to survive; graft not as thick so easier for imbibition and subsequent revascularization to occur
FTSGs
have less wound contraction; good for areas such as palms and back of hands
burn wound infections
usually apply bactracin or neosporin immediately after burns
- no role for prophylactic IV antibiotics
- pseudomonas is most common organism in burn wound infection, followed by staph, e. coli, enterobacter
- more common in burns > 30% BSA
- topical agents have decreased incidence of burn wound bacterial infections
Silvadene (silver sulfadiazine)
can cause neutropenia and thrombocytopenia; dont use in pts with sulfa allergy; limited eschar penetration; effective for Candida
Silver nitrate
can cause electrolyte imbalances; hyponatremia, hypochloremia, hypocalcemia, hypokalemia; discoloration; limited eschar penetration
Sulfamylon (mafenide sodium)
painful application
- metabolic acidosis due to carbonic anhydrase inhibition (decrease renal conversion of H2CO3 –> H20 + CO2) can cause hypersensitivity reactions
- good eschar penetration
- good for burns overlying cartilage
- broadest spectrum against Pseudomonas and GNRs
Burn wound sepsis
usually from Pseudomonas
HSV
most common viral infection in burn wounds
< 10^5 organisms
not a burn wound infection
best way to detect burn wound infection
biopsy of wound
Complications after burns
- seizures - usually iatrogenic and related to Na concentration; can also be benzo withdrawal
- peripheral neuropathy - 2/2 small vessel injury and demyelination
- ectopia - from contraction of burned adnexa; tx: eyelid release
- eyes - fluorescein staining to find injury; tx: topical fluoroquinolone or gentamycin
- corneal abrasion - tx: topical abx
- symblepharon - eyelid stuck to conjunctiva; tx: release with glass rod
- heterotopic ossification of tendons - tx: PT; may need surgery
Curling’s ulcer
gastric ulcer that occurs with burns
Marjolin’s ulcer
highly malignant squamous cell CA that arises in chronic nonhealing burn wounds or unstable scars
Hypertrophic scar
usually occurs 3-4 months after injury 2/2 increase 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
- wait 1-2 years before scar modification
- tx: grafting, steroids, silicone, compression
Toxic epidermal necrolysis (TEN) and staphylococcal scalded skin syndrome
epidermal-dermal separation seen
- caused by variety of drugs (dilantin, bactrim, PCN) and viruses
- tx: supportive, need to prevent wound desiccation with topical antimicrobials and xenografts
- abx if due to staph aureus
- no steroids
Steven Johnson syndrome (erythema multiforme)
less severe form of TEN
- hypersensitivity reaction - subepidermal bullae, epidermal cell necrosis, dermal edema
- caused by variety of drugs (dilantin, bactrim, PCN) and viruses
tx: supportive; need to prevent wound desiccation with topical antimicrobials and xenografts - no steroids
