moderate to severe burn patients
Nutritional support represents one among the foremost important cornerstones within the management of patients with a moderate to severe burn injury.
Clinical monitoring is that the key tool for assessment of the adequacy of nutritional support. Laboratory markers for immune reaction, indirect calorimetry, and weight and composition also are used.
This topic reviews assessment of the adequacy of nutritional support in burn patients.
Patient selection, timing, delivery, and kinds of nutrition support, calculating caloric requirements for burn patients and selection of enteral formula are discussed elsewhere.
CLINICAL MONITORING TOOLS
The adequacy of nutritional support is monitored by assessing the patient’s clinical course and wound healing.
Trends, instead of single measurements or point estimates, should be monitored.
Parameters wont to evaluate the clinical course include:
• Hemodynamic stability
• Respiratory status
• Functional status
• Evidence of infection or sepsis
• Tolerating diet
An experienced clinician should evaluate the patient’s burns daily.
Assessment of the wound includes recording size, depth, condition of the bottom, and pain.
This examination allows for early identification of delayed or inadequate wound healing, both of which are markers of nutritional deficiencies .
Total weight (TBW) measures two components: lean weight (muscles, bones, tendons, ligaments, and water) and fat weight. While measurements of TBW are helpful in evaluating nutritional status in healthy individuals, the numerous volume of fluid required for resuscitation in burn patients limits its value to assess nutritional status, particularly during the acute phase of burn care.
The daily measurement of TBW is employed within the majority of burn centers within the u. s. mutually indicator for monitoring and evaluating nutritional status.
Long-term trends in TBW are a helpful indicator of nutritional status when patients enter the rehabilitative phase of burn care.
LEAN BODY MASS
Maintenance of lean body mass (LBM) represents one in every of the central tenets of nutritional support in burn patients.
LBM theoretically will be monitored using body composition technology like total body potassium counting (K-counter), dual X-ray absorptiometry (DEXA) scanning, and bioimpedance analysis (BIA).
We don’t use any of those technologies, as further studies are needed to work out the utility and appropriateness of routine use within the burn care setting.
No studies of BIA are published in burn patients, though the bedside nature of BIA makes it convenient as a routine clinical tool.
Both K-counter and DEXA are routinely employed in long-term studies of pediatric burn patients, but haven’t been used as a routine component for evaluating clinical nutrition status.
Body composition assessment by current techniques can’t be reliably used as a method to watch nutritional status in burn patients due to the edema and fluid shifts related to the inflammatory response to the burn injury.
INDIRECT CALORIMETRY ASSESSMENT
Indirect calorimetry (IDC) may be accustomed determine the nutritional requirements, likewise as function an indicator of response to nutritional support, particularly within the difficult to manage patient.
The utility of IDC is controversial, particularly as one measurement point.
One of the best limitations of IDC is that energy expenditure fluctuates with activity.
We recommend using trends in IDC as a more reliable estimate of adequate nutritional support than one measurement.
IDC is monitored twice per week in our center, with adjustments in nutritional support occurring no over twice per week based upon trends in IDC, balance data, and clinical progress.
Two-thirds of responding centre dieticians indicated that they used IDC to assess energy demands in adult patients.
The assessment of adequate nutritional support must address both energy requirements and protein demands of burn patients.
balance, therefore, plays a very important role in assessing nutritional adequacy following burn injury.
Measuring urinary urea nitrogen (UUN) and calculating balance on a weekly basis allows approximation of the trend in nitrogen breakdown and appropriate adjustment of protein goals, particularly when employed in conjunction with the previously described methods of nutrition status monitoring.
In children with severe burns, UUN is imprecise, reflecting the diminished reliability of UUN measurements in patients with hypercatabolic responses
The physiologic changes that accompany a burn injury make it difficult to accurately interpret laboratory markers.
The practice at our center is to not use visceral proteins (eg, albumin) to watch nutritional status, as our experience with them has been unreliable. Furthermore, while there are markers that correlate with compromised nutritional status, they are doing not provide a meaningful measure of overall trends in nutritional status for burn patients.
Serum albumin doesn’t correlate with balance in burn patients.
Serum albumin levels decrease dramatically with injury and remain chronically depressed following burns, even when other indicators suggest adequate nutritional support.
Inflammatory response proteins
We don’t monitor the adequacy of nutritional support with transthyretin, transferrin, retinol-binding protein, and C-reactive protein during the convalescent phase.
If these protein markers are monitored, we recommend that they be used only in conjunction with the assessment of the clinical course and wound healing.
Transthyretin (prealbumin), C-reactive protein, retinol-binding protein, and transferrin have all been considered as laboratory markers for assessing the efficacy of nutritional support in burn patients.
Transthyretin, like albumin, decreases dramatically following burn injury, although it gradually recovers with adequate nutrition and because the inflammatory response subsides.
there’s a positive association with transthyretin level and wound healing and a particularly weak association with balance.
In a cross-sectional study of fifty burn patients, transthyretin was the factor significantly related to graft healing.
Transthyretin levels that don’t improve with adequate nutrition and a normalizing C-reactive protein is also indicative of either a protein or calorie deficiency.
Retinol-binding protein and transferrin didn’t demonstrate a meaningful correlation with balance.
SUMMARY and suggestions
Nutritional support represents one in all the foremost important cornerstones within the management of patients with a moderate to severe burn injury.
• The adequacy of nutritional support is best assessed by the clinical course and wound healing.
• When utilized in conjunction with daily clinical assessment, evaluating trends in total weight, indirect calorimetry, and laboratory results is helpful in assessing adequacy of nutritional support.
• Single random measurements aren’t useful.
• Most burn centers measure total weight (TBW) daily.
• The long-term trend in TBW may be a helpful indicator of nutritional status when patients enter the rehabilitative phase of burn care.
• Maintenance of lean body mass (LBM) is one in all the central tenets of nutritional support in burn patients, but there’s no proven method for accurate assessment of LBM.
• We make adjustments in nutritional support no over twice per week based upon trends in indirect calorimetry, urinary urea nitrogen, and clinical progress.
• Laboratory tests are difficult to accurately interpret following a burn injury. If laboratory tests are wont to assess nutritional status, they must be utilized in conjunction with the assessment of the clinical course and wound healing