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Infections in Burns in Critical Care
Steven E. Wolf and Basil A. Pruitt, Jr.
Division of Trauma and Emergency Surgery, Department of Surgery, University of Texas Health Science
Center, San Antonio, and Burn Center, United States Army Institute of Surgical Research,
San Antonio, Texas, U.S.A.Seung H. Kim
Burn Center, United States Army Institute of Surgical Research, San Antonio, Texas, U.S.A.INTRODUCTION
Over one million people are burned in the United States every year, most of whom have minor
injuries and are treated as outpatients. However, approximately 60,000 per year have burns
severe enough to require hospitalization. Roughly 3000 of these die (1). Burns requiring
hospitalization typically include burns of greater than 10% of the total body surface area
(TBSA), and significant burns of the hands, face, perineum, or feet.
Between 1971 and 1991, burn deaths from all causes decreased by 40%, with a
concomitant 12% decrease in deaths associated with inhalation injury (2). Since 1991, burn
deaths per capita have decreased another 25% according to the Centers for Disease Control
(Fig. 1) (3). The graph shows burn deaths have been decreasing by approximately 124 per
100,000 population per year on a linear basis for the last 20 years (r
2
= 0.99), which has been
most pronounced in the African-American population. These improvements were likely due to
effective prevention strategies resulting in fewer burns and burns of lesser severity, as well as
significant progress in treatment techniques.
Improved patient care of the severely burned has undoubtedly improved survival. Bull
and Fisher first reported in 1949 the expected 50% mortality rate for burn sizes in several age
groups (LA 50 ). They reported that the LA 50 burn was 49% TBSA for children aged 0 to 14, 46%
TBSA for patients aged 15 to 44, 27% TBSA for patients aged 45 and 64, and 10% TBSA for
patients 65 years and older (4). These dismal statistics have dramatically improved, with the
latest reports indicating 50% mortality for 98% TBSA burns in children 14 and under, and 75%
TBSA burns in other young age groups (5,6). Therefore, a healthy young patient with any
size burn might be expected to survive (7). The same cannot be said, however, for those aged
45 years or more, where improvements have been much more modest, especially in the
elderly (8).
Reasons for these dramatic improvements in mortality after massive burn that are related
to treatment generally include better understanding of resuscitation, improvements in wound
coverage, improved support of the hypermetabolic response to injury, enhanced treatment of
inhalation injuries, and perhaps most importantly, control of infection.
Burn mortality can generally be divided into four causes:
- Immolation and overwhelming damage at the site of injury, with relatively
immediate death - Death in the first few hours/days due to overwhelming organ dysfunction associated
with burn shock - Death due to medical error at some time during the hospital course
- Development of progressive multiple organ failure with or without overwhelming
infectious sepsis, highlighted by the development of the acute respiratory distress
syndrome and cardiovascular collapse
The first cause is generally unavoidable other than by primary prevention of the injury.
The second cause is unusual in modern burn centers with the advent of monitored
resuscitation as advocated by Pruitt et al. (9) and Baxter and Shires (10). The third cause is
minimized by appropriate medical care, and is being rectified to some extent by the institution