Emergency Treatment of Severely Burned Pediatric Patients: Current Therapeutic Strategies

Gerd G. Gauglitz; David N. Herndon; Marc G. Jeschke

Disclosures

Pediatr Health. 2008;2(6):761-775. 

In This Article

Fluid Resuscitation

Severe burn causes significant hemodynamic changes, which must be managed carefully to optimize intravascular volume, maintain end-organ tissue perfusion and maximize oxygen delivery to tissues.[14] Massive fluid shifts after severe burn injury result in the sequestration of fluid in both burned and nonburned tissue.[18] The release of proinflammatory mediators early on postburn, such as histamine, bradykinin and leukotriene, leads to increased microvascular permeability, generalized edema and burn shock, a leading cause for mortality in severely burned patients.[19,20,21] Therefore, the early and accurate fluid resuscitation of patients with major burns is critical for survival.[13] Calculations of fluid requirements are based on the amount of body surface involved in second- or third-degree burns (not in first-degree burns). The rule-of-nines (Figure 1) is commonly utilized to estimate the body surface area (BSA) burned, but this does have limitations in the pediatric patient population where the head is proportionally larger than the body when compared with the adult. A more accurate assessment can be made of the burn injury, especially in children, by using the Lund and Browder chart, which takes into account changes brought about by growth (Figure 2). Many different fluid-resuscitation formulas have been suggested, each can be used effectively in order to resuscitate a severe burn. The various formulas differ in the amount of crystalloid and colloid given, as well as in the tonicity of the fluid.[14] The American Burn Association (ABA) has recently published practice guidelines on burn-shock resuscitation in order to review the principles of resuscitation after burn injury, including type and rate of fluid administration and the use of adjunct measures. It presents an excellent approach for the initial treatment of burn patients.[22] However, it is important to mention that there is no formula that will accurately predict the volume requirements of the individual patient; all resuscitation formulas are designed to serve as a guide only. The modified Brooke and Parkland formulas,[23] are the most commonly used early resuscitation formulas throughout the world.[24] They use 2-4 ml/kg/% BSA burn of lactated Ringers solution. The calculated needs are for the total fluids to be administered over 24 h.[21] In children, maintenance requirements must be added to the resuscitation formula. For this reason, we recommend the Shriners Burns Hospital-Galveston formula, which calls for an initial resuscitation with 5000 ml/m2 BSA burn/day plus 2000 ml/m2 BSA/day of lactated Ringers solution.[25] For both formulas, the first half is administered within the first 8 h after the burn, and a quarter of each in the next 16 h. Intravascular volume status must be still re-evaluated on a frequent basis during the acute phase. Fluid balance during burn-shock resuscitation is typically measured by an hourly urine output via an indwelling urethral catheter. It has been recommended to maintain a urine output of approximately 0.5 ml/kg/h in adults[26] and between 0.5 and 1.0 ml/kg/h in patients weighing less than 30 kg;[26] however, there have been no clinical studies identifying the optimal hourly urine output to maintain vital organ perfusion during burn-shock resuscitation. Diuretics are generally not indicated during the acute resuscitation period. It is imperative to avoid over-aggressive resuscitation, particularly in small children below the age of 4 years, which may potentially lead to increased extravascular hydrostatic pressure and pulmonary edema.[6] This is especially important in patients who have a concomitant inhalation injury, because they will also have increased pulmonary vascular permeability. Patients with high-voltage electrical burns and crash injuries with myoglobin and/or hemoglobin in the urine have an increased risk of renal tubular obstruction. Therefore, in these patients, sodium bicarbonate should be added to intravenous fluids in order to alkalinize the urine, and urine output should be maintained at 1 and 2 ml/kg/h as long as these pigments are in the urine.[11] The addition of an osmotic diuretic, such as mannitol, may be needed to assist in clearing the urine of these pigments. Since large volumes of fluid and electrolytes are administered both initially and throughout the course of resuscitation, it is important to obtain baseline laboratory measurements of complete blood count, electrolytes, glucose, albumin and acid-base balance.[28] Crystalloid, in particular, lactated Ringer's solution, is the most popular resuscitation fluid currently utilized.[25] Proponents of the use of crystalloid solutions alone for resuscitation report that other solutions, specifically colloids, are not better and are certainly more expensive than crystalloids for maintaining intravascular volume following burn trauma.[29] Perel and Roberts identified 63 trials comparing colloid and crystalloid fluid resuscitation across a wide variety of clinical conditions and found no improvement in survival when resuscitated with colloids.[30] The use of albumin in burns and critically ill patients has recently been challenged by the Cochrane Central Register of Controlled Trials, which demonstrated no evidence that albumin reduces mortality in this particular patient population when compared with cheaper alternatives, such as saline.[31] Vincent and colleagues demonstrated in a cohort, multicenter, observational study that albumin administration was associated with decreased survival in a population of acutely ill patients when compared with those who did not receive any albumin at any time through out their intensive care unit (ICU) stay. It is worth noting that in this study, albumin-receiving patients were more severely ill than patients who did not receive any albumin.[32] However, most burn surgeons agree that burn patients with very low serum albumin during burn shock may benefit from albumin supplementation to maintain oncotic pressure.[33]

Figure 1.

Estimation of burn size utilizing the rule-of-nines.
BSA = Body surface area.
Reproduced with permission from [138].

Figure 2.

Estimation of burn size utilizing the Lund and Browder method.
Reproduced with permission from [138].

Comments

3090D553-9492-4563-8681-AD288FA52ACE
Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.
Post as:

processing....