| | Practical guidelines for nutritional management of burn injury and recoveryAccepted 25 June 2006. Abstract Nutrition practice in burn injury requires a multifaceted approach aimed at providing metabolic support during a heightened inflammatory state, while accommodating surgical and medical needs of the patient. Nutritional assessment and determination of nutrient requirements is challenging, particularly given the metabolic disarray that frequently accompanies inflammation. Nutritional therapy requires careful decision making, regarding the safe use of enteral or parenteral nutrition and the aggressiveness of nutrient delivery given the severity of the patient's illness and response to treatment. With the discovery that specific nutrients can actually alter the course of disease, the role of nutrition support in critical illness has shifted from one of preventing malnutrition to one of disease modulation. Today the use of glutamine, arginine, essential fatty acids, and other nutritional factors for their effects on immunity and cell regulation is becoming more common, although the evidence is often lagging. An exciting dichotomy exits, forcing nutrition support specialists to make responsible choices while remaining open to new potential helpful therapeutic options. 1. Introduction  Effective nutritional therapy in burn patients involves an understanding of the physiologic and metabolic alterations that accompany traumatic injury. Nutritional support must also accommodate the surgical and medical needs of the patient. The mode of therapy provided, such as route of administration and the aggressiveness of nutrient delivery depends on the severity of the patient's illness and response to treatment. Accordingly, nutritional objectives vary throughout the hospital course as the patient's clinical status changes. The following serves as a guideline for providing nutritional therapy to burned patients throughout the continuum of care. When possible, practice guidelines are evidence-based, however the myriad differences in approaches to burn care and the individual needs of patients preclude a rigid, inflexible approach to nutritional support in this population. 2. Nutritional assessment 2.1. Determining nutritional status and nutrition risk In burn patients, nutritional status is coupled to the stage of injury. Nutritional assessment consequently is a dynamic, ongoing process. At the time of admission, factors related to the patient's pre-burn history (including days post-burn, prior burn care and any complicating injuries), pre-injury height and weight, and clinical appearance serve as the basis for the patient's initial nutritional assessment. Patients who are malnourished (often those patients whose admission is significantly delayed from the time of injury) should be quickly identified since they are at greatest risk for re-feeding syndrome with the initiation of nutrition support [1], [2]. They may also benefit from brief intervals of care dedicated to nutritional rehabilitation before further surgical treatment or prior to discharge. In tandem with nutritional status, nutritional risk should be determined. Nutritional risk relates not only to pre-existing nutritional status, but also to factors that can alter the patients’ ability to receive and utilize nutrients during their hospital stay such as the severity of burn, age, and complicating conditions such as inhalation injury and organ dysfunction. As the patient progresses into the acute phase of injury, the physiologic response to trauma deteriorates nutritional status regardless of their initial baseline. Driven by a series of inflammatory mediators, catecholamines, and counter regulatory hormones, this catabolic state triggers whole body protein breakdown, ultimately diminishing the body cell mass (BCM; the metabolically active component of the body), the primary component of which is skeletal muscle [3], [4], [5]. Since diminution of the BCM directly and adversely relates to outcome, monitoring and preservation of BCM and more specifically skeletal mass becomes the primary objective of most nutrition support strategies [6]. 2.2. Evaluating nutritional adequacy A number of assessment tools serve as proxies for BCM. However, because they rely on assumptions that do not hold true during metabolic stress, they are of limited use in the critically ill burn patient. In fact, most nutritional assessment tools available in a clinical setting are confounded by the physiological elements of the inflammatory response. Even the simplest measures of total body weight or weight change, which are usually reasonable markers of fat and lean tissue status, are obscured by the expansion of extracellular water following acute burn injury [7]. Visceral proteins are better prognostic indicators than parameters of protein status in burn patients during the acute phase response [8], [9]. Overestimates of nitrogen intake and underestimates of nitrogen output often invalidate nitrogen balance studies, leading to falsely positive results. In burn injury, the magnitude of error is even further compounded by exudative wound losses and increased ammonia (versus urea) nitrogen excretion that is typical in critical illness [10], [11], [12]. Despite their limitations, many of these markers of nutritional status when trended or used collectively can help the clinician in monitoring day to day efficacy of diet therapy. The frequency of their use depends on the phase of care (Table 1). For example, while weights are often confounded by fluid changes, they can be useful when tracked over time and evaluated in the proper context. Recognition that changes in weight during the early acute phase of care may not denote changes in dry weight is important, however once the patient becomes more stable, a new “baseline” dry weight value can be used for the purpose of nutrition planning and even medication dosing. With respect to the latter, medications that are titrated to effect (i.e. morphine, fentanyl, midazolam, lorazepam, ketamine, cisatracurium, epinephrine, norepinephrine, dopamine, and dexmedetomidine) or monitored by serum level (i.e. aminoglycosides, vancomycin) should not be changed if a significant weight change occurs [13]. With respect to the former, updating the weight helps reduce undue concern over exaggerated weight loss later in the course of care. Trended weight information also helps to identify erroneous values that occur with changes in dressing types, splints, and type of scale used. | a Nutritional status/risk. |
Interpretation of visceral protein levels also depends on the phase of injury, primarily since this relates to the patient's degree of physiological stress. Defects in both the synthesis and catabolism of albumin as noted by its shortened half-life is following injury make it a poor marker of nutritional status initially [14]. However it can be trended later on in the course of injury, as the acute phase response subsides, or at follow-up visits. Interpreting visceral proteins with high turnover rates in conjunction with measures of acute phase proteins is a good way of assessing nutritional status during the early acute phase of burn injury [15]. When nutritional intake is adequate, a gradual increase in pre-albumin should occur as the acute phase subsides (as represented by a decrease in C-reactive protein, for example). Persistently low pre-albumin levels in the presence of normalizing C-reactive protein may be a sign of protein or calorie deficiency [16]. Likewise, urinary nitrogen excretion can also be used to evaluate the efficacy of nutritional care [17]. While formal nitrogen balance studies can be cumbersome and potentially flawed, serial measures of urinary urea nitrogen levels approximate (albeit imprecisely) the extent of nitrogen breakdown. Table 2 highlights this approach of combining parameters to determine nutritional adequacy during the various phases of injury. Note that part of this approach includes traditional evaluation of actual energy and protein intake in relation to estimated or measured requirement. Setting tolerable levels of intake that will support adequate wound healing and weight loss is a pragmatic, inexpensive outcome-based approach to determining nutritional adequacy [18]. 2.3. Determination of energy and protein requirements 2.3.1. Metabolic factors that influence macronutrient utilization Like nutritional assessment, inflammation and its effects on metabolism essentially serve as the backdrop for nutrition support planning. Thus, metabolic derangements resulting from stress unfortunately limit the ability to offer optimal nutrition. Following severe injury, increased cellular production of cytokines and other mediators, while a necessary mechanism for survival, puts macronutrient substrate metabolism in disarray [19], [20]. Enhanced rates of glucose production, appearance and uptake, accompanied by decreased responsiveness of liver and peripheral tissue to insulin, results in unusually high insulin requirements to achieve normoglycemia. While there is no impairment in the rate of glucose oxidation when compared to normal subjects, a lower percentage of glucose uptake is converted to carbon dioxide [21]. The rest appears to be accounted for by lactate, a possible alternative for further recycling by the liver [22]. This phenomenon is the rationale for capping glucose infusion rates at a maximum of 5 mg/kg minute despite the apparent need by the patient for more calories [23]. Increased cortisol levels stimulate muscle proteolysis, protein breakdown, and protein oxidation [24]. These high rates of protein oxidation account for a large portion of elevated energy expenditure in burn patients [25]. Difficulty replenishing diminished intracellular concentrations of specific amino acids such as glutamine and arginine, due to their increased flux and disposal from protein pools further contributes to muscle protein catabolism [26], [27], [28]. In fact, exogenous protein, while capable of enhancing protein synthesis, cannot totally abate muscle protein breakdown despite high nitrogen intakes. Lastly, enhanced lipolysis combined with impaired fat oxidation results in futile recycling of free fatty acids and triglycerides [20]. In many instances, provision of exogenous fat only exacerbates substrate recycling, and/or restores fatty tissue, making this macronutrient somewhat ineffectual in the context of wound healing and preservation of BCM. 2.3.2. Clinical factors that influence energy requirement The above-described inflammatory-nutrient interactions are part of a well-known, universal phenomenon that, upon activation does not differentiate according to the cause of the initial insult [3], [29]. The magnitude of the inflammatory response however is proportional to some degree to the severity of trauma. In addition, various clinical interventions can affect or amplify this metabolic state, further influencing energy requirements. For example, the combined effects of the inflammatory response and evaporative cooling on heat loss (and subsequently metabolic rate), place burn-injured patients among the most hypermetabolic. Conversely early excision and grafting and the use of occlusive dressing are both crucial in minimizing this effect [30], [31]. Historically, the extent of open wound area has typically been incorporated into many empirical estimates of energy requirements for burn patients [32], [33]. This method of estimating energy needs appears reasonable, however many equations that incorporate wound size overestimate actual measured energy expenditure [34], [35]. Furthermore, metabolic rate can remain elevated despite wound closure. The latter may be explained by continued transcutaneous water losses across freshly healed wounds [36], or a prevailing hypermetabolic state, although this requires further study [4]. Clinicians also should be mindful that various aspects of clinical practice, including: environmental measures to minimize heat loss, pain management, sedation, ventilatory support and nutritional therapy all contribute to a patient's overall energy expenditure, often incongruently. While energy expenditure in critically ill seems to have decreased over the past several decades in light of many advances in care, intervening clinical factors specific to each individual patient should be considered when estimating a patient level of stress. Table 3 illustrates a variety of such physiologic conditions/traits and therapeutic interventions that can influence energy expenditure. To the extent that they influence metabolic rate, an awareness of these clinical factors, particularly those that prevail in one's own clinical arena, is important in estimating calorie goals. For example, a patient who has good pain control, is well sedated, and working little towards the effort of breathing while mechanically ventilated may have lower requirements than a patient who is less critically ill, breathing on their own with less sedation and more participation in rehabilitation. In other words, some patients, as they get better may actually have increased daily energy requirements. 2.3.3. Indirect calorimetry From the above, it is apparent that energy requirements vary from patient to patient, as well as from one burn unit to another based on standards of burn practice. This makes it difficult and perhaps unwise to generalize energy needs in burn patients. Serial measures of resting energy expenditure by indirect calorimetry, if available, diminish the degree of pure estimate by capturing the stress of disease as well as the effect of many of the clinical factors mentioned in each measurement. This can help avoid over- and under-feeding [37]. Because such measures only reflect a “brief moment in time”, a factor, which rarely exceeds 30% of the measured metabolic rate, is usually applied to account for activities throughout the day that may contribute to 24-h energy expenditure [38]. The degree of estimation with this method is minimized, and use of serial measures allows energy provision to stay in tune with the change in clinical status. While it is difficult to link indirect calorimetry with improved outcome, overfeeding patients leads to undesirable complications such as fatty liver, hyperglycemia and fluid overload. Moreover, overzealous feeding tends to lead to the accumulation of fat versus lean body mass, therefore of little benefit. Such consequences are likely to be avoided with indirect calorimetry since most formulas overestimate requirements [39], [40], [41]. It is our practice to measure energy expenditure whenever clinically feasible. When it is necessary to predict energy requirements, we base energy goals on a patient's estimated resting metabolic rate and apply a factor (usually between 1.0 and 1.75 is used in our unit) that encompasses a combination of clinical and physiologic elements. This factor is evaluated periodically. Either method is preferred to a static estimate that does not account for changes in a patient's clinical status. 2.3.4. Estimation of protein needs Severe burn is characterized by increased amino acid efflux from the skeletal muscle presumably to accommodate amino acid needs for tissue repair, acute-phase protein production, cellular immunity, and gluconeogenesis [4]. Intuitively, inadequate protein intake compromises wound healing, muscle function, and the immune system. Therefore, the objective of protein therapy during after burn is to provide sufficient quantity and quality of amino acids in the diet so as to (1) avert their outflow from skeletal muscle and (2) maximize protein synthesis for optimal wound healing and immune function. Unlike simple balance studies, protein dynamic studies allow us to look beyond the net aspects of protein metabolism by isolating actual rates of both protein synthesis and protein breakdown [5]. This has been helpful in reaching protein goals and establishing realistic outcomes. For example, in adults, protein intakes approaching 1.5g/kg/day were associated with a net balance between protein synthesis and breakdown. Protein intake greater that 1.5gprotein/kg/day, while stimulating absolute rate of both synthesis and breakdown, did not further benefit net protein synthesis [42], and was not shown to provide any advantage. As previously mentioned, isotopic evidence also shows that protein breakdown cannot be completely abated by exogenous protein following burn [42], [43]. Therefore some lean body mass losses can be expected despite adequate protein intake [44]. In fact, it may be that adjunctive anabolic therapy is necessary for optimal preservation of lean body mass [45]. On the other hand, dietary protein alone can improve protein economy, which in turn can enhance increased structural and functional protein synthesis and improve wound healing time [43]. 3. Nutrition support strategies Once energy and protein requirements are established, the mode of nutrient delivery that best meets both the metabolic and clinical needs of the patient is determined. Recognizing the importance of maintaining gut mucosal integrity, most clinicians opt to use enteral nutrition as the preferred mode of therapy [46]. In response, enteral feeding strategies have become increasingly sophisticated and enable considerable flexibility in the initiation, advancement, and composition of enteral nutritional therapy [47]. However the ease in which enteral nutrition can now be provided, should be tempered by sound clinical judgment, in particular to avoid complications of overzealous feeding in the critically ill patient who may be intolerant. So while the debate of enteral versus parenteral nutrition therapy in a general sense seems obsolete, guidelines for practice should ensure that the benefits of enteral nutrition outweigh the potential risks to any given patient are needed. 3.1. Combined enteral and parenteral nutrition during the early acute phase of injury The parenteral route of support has been criticized because it is not physiologic, does not provide adequate nutrition to the gut, and has been associated with a higher rate of complications in critically ill surgical patients [48], [49], [50], [51]. However, parenteral nutrition has the advantage of being tolerated by patients who are severely ill and when used properly, is safe in patients who are undergoing frequent surgery [52], [53]. Furthermore, it is the lack of enteral as opposed to provision of parenteral nutrition that is most frequently linked with gut barrier failure and infection [54], [55]. For several years it has been our practice to use gastric tube feedings combined with supplemental parenteral nutrition, the latter during periods of gastric tube feeding intolerance, hemodynamic instability, septic episodes, or surgery. Retrospective analyses has proven that this practice is safe and effective in our population in terms of adequate calorie and protein intakes, promotion of wound healing, and mortality [18], [53], [56]. We attribute the success of this approach to three key elements: (1) judicious enteral feeding support according to clinically defined indicators (Table 4); (2) provision of parenteral nutrition based on substrate utilization versus calorie estimate; (3) discriminate use of intravenous lipids. Coincidently, the latter two characteristics result in nutritional therapy that provides a low to moderate calorie intake, which has also been shown to improve outcomes [57]. 3.1.1. Enteral feeding guidelines in early recovery Upon admission patients are evaluated for their ability to receive enteral feedings according to their clinical status. Those undergoing aggressive fluid resuscitation are considered at risk for poor intestinal perfusion. Although enteral feedings may actually improve gut perfusion to some degree, the potential imbalance between intestinal oxygen demand and perfusion warrants caution during this phase of injury [58]. To date, research has failed to demonstrate strong clinical outcome benefit associated with early enteral feeding [59], [60], [61], [62]. Conversely, reports of feeding-induced bowel necrosis in enterally fed, critically ill patients is disconcerting, particularly as clinical indicators to predict this occurrence are lacking [63], [64]. Therefore, it is our practice to provide only trophic feeds in patients at risk for diminished gut perfusion. This includes patients who require significant vasopressor requirement [59], [65]. Once patients are hemodynamically stable and able to wean from their vasopressor support, their gastric tolerance is assessed. Patients with low GI output (less than 200mL) and stable abdominal girth (baseline is obtained upon admission) are initiated on gastric feedings at an hourly rate of 0.5–1mL/kg. They are then quickly advanced unless residuals exceed two times their hourly rate. 3.1.2. Parenteral nutrition composition Because parenteral support has been linked to increased rate of infections and hepatic dysfunction, careful consideration of the composition (Table 5) and rate of administration of solution, as well as proper line care is used when providing this form of nutrition [49], [50], [66]. In our hospital, the use of one standardized solution has reduced costs, potential for error, and metabolic aberrations that are often attributed to parenteral nutrition. For example, goal volume for parenteral nutrition is determined by the rate of substrate utilization as opposed to a predetermined energy goal (Table 6). This prevents overfeeding of intravenous nutrients that can potentially contribute to hepatic steatosis, fluid edema, and other metabolic derangements. Our findings that glucose infusion rates in excess of 5μg/kg/min are not oxidized efficiently by adults or children [67] provide the basis for goal infusion rates in all burn patients. This too helps to minimize the incidence of hyperglycemia [68]. Amino acid infusions are targeted to meet 100% of estimated protein requirement. This usually results in a non-protein calorie:nitrogen ratio of 85:1, which is consistent with enhanced wound healing [69], [70]. Monitoring guidelines for patients on TPN, according to their level of acuity, are provided in Table 7. 3.1.3. Discriminate intravenous lipid administration Because they may interfere with platelet function, are associated with poor immune function, and may exacerbate lung injury in some situations [71], [72], [73], [74], intravenous lipids are avoided unless parenteral support must be provided in excess of 3 weeks. Since intravenous lipids have a high propensity for fatty acid-tryglyceride recycling during inflammation and appear to be less protein sparing than glucose, their omission seems inconsequential from a metabolic standpoint [75], [76], [77]. Although signs of essential fatty acid deficiency are likely obscured during burn injury, a small amount of intravenous lipids are given if enteral nutrition cannot be started by week 3 of admission. This however is rarely necessary, particularly since many patients advance to full enteral support by then. Patients may also receive essential fatty acids during propofol infusions. Given the above constraints, it is commonly not possible to deliver all predicted caloric requirements with this regimen. Most of our patients receive an average of 110–130% of their basal metabolic rate. However, when protein is strictly maintained at goal rate, good surgical outcomes can be achieved, with minimal weight loss during these brief periods. Furthermore, parenteral support provided during escalation of tube feedings will lead to more prompt achievement of calorie and protein targets, without complications attributed to the mode of feedings. 3.2. Enteral nutrition Historically, the notion that starvation and protein malnutrition lead to mucosal atrophy served as the impetus for increased reliance on enteral nutrition in hospitalized patients. Knowledge that stress may increase intestinal permeability, a proposed mechanism in bacterial translocation, further advanced the concept of enteral nutrition as being important in immunity [78], [79], [80]. While there is little to no direct evidence that enteral nutrition prevents bacterial translocation in humans, the impact of intraluminal nutrition on gastrointestinal tract in immunity appears to be important [81], [82]. Moreover, new theories are emerging, linking gut ischemia/reperfusion in the development of sepsis and multiple organ failure following trauma and burn [83], [84], [85]. Enteral nutrition therefore is advocated not only to maintain gut integrity, but also to minimize the release of gut-derived mediators that can activate inflammatory cascades that result in free radical damage [86]. Clinically, enteral feedings have a lower risk of infectious complications, are more physiologic and (usually) more cost effective than parenteral support, and are well tolerated in most burn patients. 3.2.1. Formula selection Historically, and to date, enteral supplements have been used to maintain nutritional status and divert negative outcomes associated with malnutrition. In this sense, standard polymeric feedings remain common practice in severe burns and are likely to be sufficient for supporting wound healing and lean body mass when energy and protein intakes are sufficient. Their favorable cost, compared to many specialty products, and the fact that they are well tolerated, makes them a first line of choice in most hospital nutrition formularies. However, in parallel with recognition of the gut as an immune-regulating organ, several key nutrients have been identified, that when given enterally can actually affect physiological processes in response to injury. It follows in theory that formulas containing these nutrients, can actually alter the course of a given disease state. Advances in the technological development of enteral formulations over the past 20–30 years offers clinicians a wide range of such feeding options, some at considerable cost. Here, market availability has actually preceded scientific rationale for use of such products. As research in this area continues to progress however, a paradigm shift in how we view the role of nutrition in burn care management has taken place. Most specialty formulas that are of interest in burn nutrition have wound healing and/or immune enhancing properties. Among these to be discussed here are two conditionally essential amino acids glutamine and arginine. Glutamine is considered important in many disease states for its numerous properties. With two amine groups, it functions as a nitrogen shuttle, carrying nitrogen for purine and pyrimidine synthesis. Glutamine serves as a primary oxidative fuel source for rapidly dividing cells, including the enterocyte. As a precursor to glutathione, a potent antioxidant, glutamine participates in reducing oxidative damage [86]. Glutamine supplementation in burn injury has shown moderate benefit. We studied the effect of glutamine supplementation (0.6g/kg) on protein economy and found that a glutamine-enriched diet had a similar effect on protein turnover and breakdown as a mixture of essential amino acids [87]. In another study, glutamine supplementation resulted in decreased muscle protein breakdown (as indicated by 3-methyl-histidine) and improved wound healing when fed enterally. Other clinical benefits of glutamine supplementation in burn patients include reductions in infection rate, length of stay, cost, and mortality [88], [89]. Glutamine supplementation is relatively safe, making it a reasonable consideration for practice in this population. The role of arginine supplementation in burns continues to be explored. Stress-induced depletion of arginine in tissue pools suggests that it too is semi-essential after burn. Increased extrahepatic uptake of arginine contributes to accelerated urea production in burn patients further exacerbating its losses from the body [27]. This is concerning given arginine's role in wound healing (as a stimulant to growth hormone) and immunity through the nitric oxide pathway [90]. Unfortunately, uncontrolled production of nitric oxide can also be detrimental, and may have contributed to adverse clinical outcomes particularly in patients who are septic [91]. Conversely, the possible benefit of arginine in wound healing can especially be realized in malnourished patients, or patients who are not metabolically stressed, suggesting a role still in the burn population. Further studies are needed to determine safe dosing for the more critically ill patient. 3.2.2. Small bowel versus gastric feeds Controversy continues over the most effective route of gastrointestinal support: intra-gastric tube feedings or small bowel tube feedings. Proponents of small bowel tube feedings suggest that burn patients have slowed gastric emptying and that this mode of delivery will decrease the rate of aspiration pneumonia. The ability, at least in patients in whom the postpyloric location of the tube is certain, to continue enteral feedings during surgery is another major advantage and is used successfully in some burn units. Although postpyloric tubes can be placed blindly with a weighted tube, endoscopically, or using fluoroscopy, duodenal intubation can be technically challenging in many patients. Further, postpyloric tubes can be dislodged into the stomach and approximately 30% of enterally fed patients in the intensive care unit will develop diarrhea. Gastric tube feedings are tolerated when begun early after injury, obviate the high rate of diarrhea seen in those fed enterally, and can be delivered without a high risk of aspiration. In addition, gastric feeds are more beneficial in ulcer prophylaxis. They have the further advantages of being simple to administer and easy to monitor for tolerance by tube aspiration. When relying on intra-gastric feedings, infusions must be stopped peri-operatively to avoid aspiration. During these intervals, frequent in children with large burns, supplemental parenteral support can be provided (Table 4). 3.3. Micronutrient supplementation Evidence-based practice guidelines are currently unavailable for the assessment and provision of micronutrients in burn patients. Intuitively, diminished gastrointestinal absorption, increased urinary losses, altered distribution, and altered carrier protein concentrations following severe burn will lead to a deficiency in many micronutrients if not supplemented [92], [93], [94]. However, caution should be used to avoid toxicities that can result in gastrointestinal tolerance, antagonistic reactions—that can lead to deficiencies of other nutrients, and the potential for other undesirable outcomes, however subtle these may be. Knowledge of the basic properties among the various groups of micronutrients during stress is necessary, as it enables the clinician to apply sound reasoning in practice and in the development of a protocol for micronutrient monitoring and supplementation in the burn patients. There are a number of characteristics that predominate among micronutrients. Firstly, micronutrients exist in pools that are often in a state of flux. This makes static measures of certain nutrients in the blood not representative of levels in tissue “pools”. Inter-compartmental fluid shifts, acid–base balance, and recent dietary intake can all affect the presence of a given nutrient within a certain pool. Furthermore, many micronutrients, especially trace elements and fat-soluble vitamins are bound to protein carriers. This is particularly significant, since proteins are highly regulated during the acute phase response. Blood analysis of zinc, copper, selenium and iron can be misleading due to this phenomenon [94]. Even more importantly, hypoproteinemia during malnutrition or acute burn will not confound micronutrient assessment, but it can also impair the nutrient's ability to be transported from its storage form to tissues (where it is needed), making supplementation somewhat futile. This “functional” deficiency as in the case of Vitamin A, corrects only when normal protein status returns. Despite common practice in many burn units, there is little evidence to date for giving pharmacological doses of any micronutrient in burn patients. In our unit, micronutrient supplementation is aimed at correcting a deficiency state. Table 8 is our supplementation protocol for use in children. Worth mentioning is that the majority of patients actually achieve the recommended supplemental amount (above that required under normal conditions) through their standard nutritional therapy. For these patients, supplementation is not necessary. This is a notable advantage to providing adult enteral formulas to children [95]. | a Children greater than 3 years of age. bChildren receiving adult or specialty formulas designed for wound healing may not require additional supplementation of individual nutrients. cVitamins A, E, iron, B complex are provided only as part of multivitamin/trace element preparation. dAddition of a multivitamin supplement with trace elements may be sufficient for meeting requirements. |
4. Summary and conclusion Advances in infection control, early excision and grafting and aggressive nutritional support have greatly improved survival from severe burn injury. Critically ill burn patients are not homogenous. Their needs are complex and often condition specific. Many factors related to the clinical management of these patients, such as surgical needs, mechanical ventilation, and medication use influence nutritional status and the ability to feed a patient. With each change in clinical status, reassessment of nutrient requirement, type and mode of feeding is necessary. References [1]. [1]Sheridan R, Weber J, Prelack K, Petras L, Lydon M, Tompkins R. Early burn center transfer shortens the length of hospitalization and reduces complications in children with serious burn injuries. J Burn Care Rehabil. 1999;20:347–350. MEDLINE |
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PII: S0305-4179(06)00202-6 doi:10.1016/j.burns.2006.06.014 © 2006 Elsevier Ltd and ISBI. All rights reserved. | |
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