Infectious Diseases in Critical Care Medicine

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of evidence-based clinical guidelines and quality improvement programs, which are becoming
the standard in intensive care units around the world. The last is the most common cause of
death for those who are treated at a burn center, and it is that which is linked to the
development of infection to the burn wound.


PREVENTION OF BURN WOUND INFECTION
Two practices have revolutionized burn care to improve outcomes by decreasing invasive
wound infections. Early excision and closure of the burn wound prevents infection by
eliminating the eschar that harbors microorganisms and providing a barrier to microorganism
growth and invasion. The other is the timely and effective use of antimicrobials both topical
and systemic. The infected burn wound filled with invasive organisms is uncommon in most
burn units due to wound care techniques and the effective use of antibiotics.
Early excision and an aggressive surgical approach to deep wounds have achieved
mortality reduction in patients with extensive burns. Early removal of devitalized tissue
prevents wound infections and decreases inflammation associated with the wound. In
addition, it eliminates foci of microbial proliferation, which may be a source of transient
bacteremia. Those transient bacteremias, most common during surgical manipulations, may
prime immune cells to react in an exaggerated fashion to subsequent insults leading to whole
body inflammation—the systemic inflammatory response syndrome (SIRS), and remote organ
damage (multisystem organ failure). We recommend complete early excision of clearly full-
thickness wounds within 48 hours of the injury, and coverage of the wound with autograft or
allograft skin when autograft skin is not available. Within days, this treatment will provide a
stable antimicrobial barrier to the development of wound infections. Barret and Herndon
described a study in which they enrolled 20 subjects, 12 of whom underwent early excision
(within 48 hours of injury) and 8 of whom underwent delayed excision (>6 days after injury).
Quantitative cultures from the wound excision showed that early excision subjects had less
than 10 bacteria/g of tissue, while those who underwent delayed excision had greater than 10^5
organisms, and three of these patients (37.5%) developed histologically proven burn wound
infection compared to none in the early excision group (11). In another study from the same
center, it was found that delayed excision was associated with a higher incidence of wound
contamination, invasive wound infection, and sepsis with bacteremia compared with the early
group when the rest of the hospitalization was considered (12). These two studies show that
the best control of the burn wound is obtained with early excision.
Before or after excision, control of microorganism growth is obtained by the use of topical
antibiotics. Available topical antibiotics can be divided into two classes, salves and soaks.
Salves are generally applied directly to the wound and left exposed or covered with cotton
dressings, and soaks are generally poured into cotton dressings on the wound. Each of these
classes of antimicrobials has advantages and disadvantages. Salves may be applied once or
twice a day, but may lose effectiveness between dressing changes. More frequent dressing


Figure 1 Per capita mortality from
burns in the United States. The rate
has been decreasing yearly at
approximately 124 deaths/100,000
persons per year (r= 0.99).

360 Wolf et al.

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