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1182 PART 10: The Surgical Patient

not be an issue in nonburn patients is assessing the airway patency and relative lack of sufficient knowledge regarding such management. 3,17,25,29
readiness to wean off the ventilator. The easiest and cheapest method Even among burn center physicians, there is considerable variability in
to assess for airway patency is to briefly disconnect the patient from determining the amount of fluids to be administered during the resus-
the ventilator, deflate the cuff on the endotracheal tube, and completely citation period.
occlude the end of the ETT. If the patient is able to breathe around the Outside of a computer generated and controlled resuscitation for-
occluded ETT, then the airway likely has enough space around the ETT mula currently being investigated by military burn surgeons, the best
for safe extubation. Prophylactic antibiotics have no role and actually resuscitation guideline is one that provides the optimal resuscitation
increase infection rates. The diagnosis of pneumonia in burn patients and the least opportunity for disaster by the inexperienced clinician.
has been described in a position paper by the ABA. For patients who fail The attached resuscitation guides have been successfully used in the
6
to respond to maximal conventional therapy, one may consider extracor- 16-bed burn center at the University of Iowa (Fig. 123-2). The adult
poreal membrane oxygenation (ECMO) as a rescue therapy for patients protocol utilizes a weight-based approach, with urine output and vital
with acute hypoxemic respiratory failure who are expected to die other- signs being monitored every hour during the resuscitation period. The
wise. ECMO has been shown to have some success in pediatric patients pediatric protocol also utilizes a weight-based approach, adding glucose
7
with severe inhalation injuries but survival in adult burn patients is containing maintenance fluids for the child <30 kg (Fig. 123-3). These
anecdotal. One problem with ECMO is that to be successful, the patient protocols have allowed us to use a protocol that provides adequate resus-
must have already undergone burn wound excision and application of citation but avoids overresuscitation and the attendant complications.
xeno/allo/autografting prior to being placed on ECMO, which can last A clinical advantage with colloid administration during the resuscita-
for up to 2 weeks. However, a conflicting criterion for successful ECMO tion phase has not been identified. 22,24,31 One study showed a decreased
is early intervention, for example, within 12 to 36 hours of burn injury. risk of death when albumin was used during resuscitation, but the dif-
18
The combination of a body burn and smoke inhalation produces a ference did not achieve statistical significance. A meta-analysis compar-
marked increase in mortality and morbidity and survival in patients ing albumin to crystalloid showed a 2.4-fold increased risk of death with
8,9
>age 60 years with inhalation injury is very low. Burn patients with albumin. Hypertonic saline has also had disappointing results, with
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inhalation injury have been shown to require increased fluids during a fourfold increase in renal failure and twice the mortality of patients
resuscitation. 1,11-14 Navar et al found that the presence of inhalation given lactated Ringer solution. Hypertonic saline does not routinely
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15
injury was associated with a 44% increase in fluid requirements, which have a place in burn resuscitation. Fresh frozen plasma should not be
19
was remarkably uniform across all age groups and burn sizes. The used as a volume expander, according to new policies on blood product
degree of lung dysfunction caused by a smoke inhalation injury is accen- delivery. Due to the risk of blood-borne infectious transmission,
22
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tuated by the presence of even a small body burn. 9,14,16,17 Although it is the American Burn Association Practice Guidelines for Burn Shock
not totally clear how much additional fluid will be required, be aware Resuscitation do not recommend the use of fresh frozen plasma without
that somewhere between 40% and 70% additional fluid will be required, active bleeding or coagulopathy outside of a clinical trial, when other
and resuscitation guidelines do not take inhalation injury into account. choices are available. Depletion of limited blood bank reserves is
21
another deterrent to using fresh frozen plasma in burn resuscitation.
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During resuscitation, development of unstable vital signs, inadequate
CIRCULATION response to fluids, or persistently high fluid requirements should prompt
Adequate resuscitation from burn shock is the single most impor- a call to an experienced burn care physician as noted in both adult and
tant therapeutic intervention in burn treatment. Due to a paucity of pediatric resuscitation protocols.
evidence-based literature, burn resuscitation remains an area of clinical It is not possible to accurately predict who will fail resuscitation, but
practice driven primarily by local custom of the treating burn units. patients who routinely require additional fluids include those with inhalation
18
The only issue exempt from debate is that fluid administration is uni- injury, electrical burns, those in whom resuscitation is delayed, and those
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versally advocated. 13,19 Each patient will react uniquely to burn injury using alcohol or illicit drugs. Patients making methamphetamine have
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depending on age, depth of burn, concurrent inhalation injury, preexist- been found to be injured more seriously with larger, deeper burns and often
ing comorbidities, and associated injuries. Formulas should be regarded require two to three times the standard Parkland formula resuscitation. 35,36
as a resuscitation guideline; fluid administration has to be adjusted to There is significantly increased inhalation injury, nosocomial pneumonia,
individual patient needs. Of the numerous formulas for fluid resus- respiratory failure, and sepsis in this patient population. 35,36
citation, none is optimal regarding volume, composition, or infusion
rate. 12,20-26 Lactated Ringer solution most closely resembles normal body RESUSCITATION GOALS
fluids. Factors that influence fluid requirements during resuscitation
besides TBSA burn include burn depth, inhalation injury, associated Effective fluid resuscitation is one of the cornerstones of modern burn
injuries, age, delay in resuscitation, need for escharotomies/fasciotomies, care and perhaps the advance that has most directly improved patient
and use of alcohol or drugs prior to injury. 27 survival. Proper fluid resuscitation aims to anticipate and to prevent
The modified Parkland formula is currently the most widely used rather than to treat burn shock. 3,20,21 Resuscitation of burn shock cannot
resuscitation guideline, used in >90% of burn centers in the United hope to achieve complete normalization of physiologic variables because
States. The Advanced Burn Life Support curriculum supports the use the burn injury itself leads to ongoing cellular and hormonal responses.
of the Parkland formula for resuscitation in burn injury. Simply put, However, moving the patient toward a normal burned physiologic
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it is 4 mL/kg/percentage TBSA, this gives the amount of lactated Ringer status during the resuscitation period is an appropriate goal. The obvious
solution required in the first 24 hours after burn injury, where kg repre- challenge is to provide enough fluid replacement to maintain perfusion
sents the patient weight in kg, and percentage TBSA (total burn surface without causing fluid overload. 3,11,12,22-25,37-43 Without effective and rapid
area) is the size of the burn injury. According to the Parkland formula, intervention, hypovolemia/shock will develop if the burns involve 15%
beginning at the time of burn injury, half of the fluid is given in the first to 20% TBSA. Delay in fluid resuscitation beyond 2 hours of the burn
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8 hours and the remaining half is given over the next 16 hours. The injury complicates resuscitation and increases mortality. 37,43 The conse-
rapid determination of percentage TBSA burn and calculation of the quences of excessive resuscitation and fluid overload are as deleterious
fluid requirements can be difficult and often incorrect when the person as those of underresuscitation: pulmonary edema, myocardial edema,
treating these burns is an inexperienced clinician. The substantial errors conversion of superficial into deep burns, the need for fasciotomies in
in estimating burn extent and depth result in significant under- or unburned limbs, and abdominal compartment syndrome. 18,19,22,44,45 A
overcalculation of fluid requirements. 25,28-30 Most doctors outside burn Lund-Browder chart should be completed at the time of admission to
centers have infrequent experience with major burn management and a calculate the TBSA burn (Fig. 123-4).

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