Marilyn Jenkins

Differential Effects of Three Enteral Dietary Regimens on Selected Outcome Variables in Burn Patients

A modular tube feeding recipe (MTF) was designed to meet the unique nutritional needs of burn patients, applying principles previously documented in our burned guinea pig model. MTF, a high-protein, low-fat, linoleic acid-restricted formulation is enriched with omega-3 fatty acids, arginine, cysteine, histidine, vitamin A, zinc, and ascorbic acid. Fifty patients, 3 to 76 years of age with burns ranging from 10 to 89% total body surface area were prospectively randomized into three groups which blindly compared MTF to two enteral regimens widely utilized in the nutritional support of burns. Age, percent total and third-degree burn, resting energy expenditure, and calorie and protein intake were similar in all groups. Data analysis demonstrated significant superiority of MTF in the reduction of wound infection (p less than 0.03) and length of stay/percent burn (p less than 0.02). MTF was also associated with a decreased incidence of diarrhea, improved glucose tolerance, lower serum triglycerides, reduced total number of infectious episodes and trends toward improved preservation of muscle mass, although statistical significance was not achieved. Seventy percent of deaths occurred in the group supported with an inherently large dose of fat and linoleic acid. Combining these observations, it is believed that MTF is effective in modulating an improved response to burn injury.

Enteral feeding during operative procedures in thermal injuries

Multiple surgical procedures necessitated by thermal trauma traditionally require withholding nutritional support during the perioperative period. Significant caloric deficits develop with subsequent catabolism of body tissues to provide energy and amino acids for the synthesis of protein. Eighty patients, matched for age and total body surface area burn, were enrolled in a study to evaluate the safety and efficacy of providing enteral support throughout operative procedures. All patients had duodenal feeding tubes placed under fluoroscopy and were provided with isonitrogenous nutritional support calculated to meet measured energy needs (indirect calorimetry). Forty patients received enteral support throughout 161 surgical procedures, and 40 had enteral support withheld during 129 procedures. Age, incidence of inhalation injury, percentage of total body surface area, and postburn day of admission were similar in both groups. Nutritional parameters, calorie counts, and infectious complications were recorded during the first 4 weeks after burn. No patient in either group experienced aspiration. The unfed group demonstrated a significant caloric deficit (p < 0.006) and increased incidence of wound infection (p < 0.02) and required more albumin supplementation to maintain serum levels at a minimum of 2.5 gm/dl (p < 0.04). Enteral nutrition can be provided safely during the perioperative period and provides the additional benefits of reducing caloric deficits, wound infections, and exogenous albumin supplementation.

The 2002 Clinical Research Award. An evaluation of the safety of early vs delayed enteral support and effects on clinical, nutritional, and endocrine outcomes after severe burns.

Early enteral support is believed to improve gastrointestinal, immunological, nutritional, and metabolic responses to critical injury; however, this premise is in need of further substantiation by definitive data. The purpose of this prospective study was to examine the effectiveness and safety of early enteral feeding in pediatric patients who had burns in excess of 25% total body surface area. Seventy-seven patients with a mean percent total body surface area burn of 52.5 +/- 2.3 (range 26-91), percent full thickness injury of 44.7 +/- 2.8 (range 0-90), and age ranging from 3.1 to 18.4 (mean 9.3 +/- 0.5) were randomized to two groups: early (feeding within 24 hours of injury) vs control (feeding delayed at least 48 hours postburn). Nutrient intake was measured daily, indirect calorimetry was performed biweekly, and blood and urine samples were obtained for the assay of cortisol, glucagon, insulin, gastrin, epinephrine, norepinephrine, dopamine, triiodothyronine, tetraiodothyronine, albumin, transferrin, prealbumin, retinol-binding protein, glucose, nitrogen balance, and 3-methylhistidine throughout the study period. Three protocol violations occurred, and two patients were transferred to another hospital; these patients were excluded from the study. No patient in either group experienced tube feeding aspiration. No differences were evident in infection, diarrhea, hospital length of stay, or mortality outcomes. A higher incidence of reportable adverse events coincided with early feeding (22 vs 8%), but this was not statistically significant. The delayed feeding group demonstrated a significant caloric deficit during postburn week (PBW) 1 (P <.0001) and PBW2 (P =.0022). Serum insulin (P =.0004) and triiodothyronine (P =.0162) were higher in the early fed group during PBW1. A decrease in 3-methylhistidine output (suggesting a decrease in protein breakdown) was also evident during PBW1 (P =.0138). No other significant trends in study outcome variables were noted. In conclusion, provision of enteral nutrients shortly after burn injury reduces caloric deficits and may stimulate insulin secretion and protein retention during the early phase postburn. These data, however, do not necessarily reaffirm the safety of early enteral feeding, nor do they associate earlier feeding with a direct improvement in endocrine status or a reduction in morbidity, mortality, hypermetabolism, or hospital stay. Future studies are needed to establish precise feeding implementation times that maximize clinical benefit while minimizing morbidity in the critically injured burn patient.

Diarrhea in tube-fed burn patients: incidence, etiology, nutritional impact, and prevention.

The hypermetabolic state observed in thermally injured patients warrants aggressive nutritional management. Enteral support is the preferred route of nutrient delivery, however diarrhea is reported to be a persistent complication of continuous nasogastric or nasoduodenal hyperalimentation. Diarrhea adds to problems in patient care, disturbs fluid and electrolyte balance, and worsens nutritional status. There has been the impression that tube feeding hyperosmolality, antibiotics, and low serum albumin induce diarrhea. However, in view of the sparsity of published work, a prospective study was undertaken to determine the incidence of diarrhea and to define factors associated with its cause. Of the 50 patients studied, 16 (32%) developed diarrhea. Stool cultures were negative for pathogenic organisms. Although the risk of diarrhea was associated with antibiotics (p less than 0.005), several nutrients also had an impact. Results demonstrated a significant relationship between dietary lipid content (p less than 0.05) or vitamin A intake (p less than 0.001) and diarrhea. Implementation of tube feeding within 48 hrs postburn was also associated with a decreased incidence of diarrhea (p less than 0.001). This paper describes a modular tube feeding program in which diarrheal frequency is lessened (p less than 0.0001). Surprisingly, tube feeding osmolality, drugs used to prevent stress ulcers, or hypoalbuminemia did not have an adverse effect on intestinal absorption. The cause of diarrhea in burn patients is obviously multifactorial. It is concluded that a low fat (less than 20% of caloric intake), vitamin A enriched (greater than 10,000 IU/day), early enteral support program maximizes conditions which promote tube feeding tolerance while minimizing nutrient malabsorption during the nutritional rehabilitation of thermal injury.

American Burn Association/Shriners Hospitals for Children burn outcomes questionnaire: construction and psychometric properties

To develop a standardized, practical, self-administered questionnaire to monitor pediatric patients with burns and to evaluate the effectiveness of comprehensive pediatric burn management treatments, a group of experts generated a set of items to measure relevant burn outcomes. Children between the ages of 5 and 18 years were assessed in a cross-sectional study. Both parent and adolescent responses were obtained from children 11 to 18 years old. The internal reliability of final scales ranged from 0.82 to 0.93 among parents and from 0.75 to 0.92 among adolescents. Mean differences between parent and adolescent were small; the greatest difference occurred in the appearance subscale. Parental scales showed evidence of validity and potential for sensitivity to change. In an effort to support the construct validity of the new scales, they were compared with the Child Health Questionnaire and related to each other in clinically sensible ways. These burn outcomes scales reliably and validly assess function in patients with burns, and the scales have been developed in such a way that they are likely to be sensitive to change over time.

The 1994 Clinical Research Award. A prospective clinical study of the polysomnographic stages of sleep after burn injury.

Although subjective evidence suggests that patients with burns are deprived of sleep, previous clinical studies have been limited to observational data and have not to date included electroencephalographic or polysomnographic recordings. The purpose of this study was to characterize the sleep pattern of patients suffering from thermal injury. Biweekly 24-hour polysomnographic measurements (electromyography, electrooculography, and electroencephalography) were performed with 12 leads. This measuring permitted continuous recording of intrinsic electrical activity in skeletal muscles via chin electrodes, eye movement via outer canthal electrodes, and brain wave activity with the other bipolar electrodes. Determinations were obtained on 11 patients with thermal injuries for a total of 43 24-hour periods. The patients had a mean age of 8.31 +/- 1.5 years (range 1.4 to 16 years), a mean total body surface area burn of 55.1% +/- 16.5% (range 17.5% to 90.5%), and a mean full-thickness burn of 48.5% +/- 8.1% (range 10.5% to 90.5%). Although mean total sleep time was seemingly adequate (625.1 +/- 31.6 min/patient/24 hrs), large aberrations in sleep stage distribution were noted. Significant decreases in stage 3 + 4 and in rapid eye movement (deep sleep) and increases in stages 1 and 2 (light sleep) were noted, suggesting a cycling back to stages 1 or 2 after disruption of sleep. Overall, in 43 runs 40% of the subjects were completely lacking stage 3 + 4, and 19% were missing rapid eye movement during an entire 24-hour run.(ABSTRACT TRUNCATED AT 250 WORDS)

The development, validation, and testing of a health outcomes burn questionnaire for infants and children 5 years of age and younger: American Burn Association/Shriners Hospitals for Children.

The 12-member American Burn Association/Shriners Hospitals for Children Outcomes Task Force was charged with developing a health outcomes questionnaire for use in children 5 years of age and younger that was clinically based and valid. A 55-item form was tested using a cross-sectional design on the basis of a range of 184 infants and children between 0 and 5 years of age at 8 burn centers, nationally. A total of 131 subjects completed a follow-up health outcomes questionnaire 6 months after the baseline assessment. A comparison group of 285 normal nonburn children was also obtained. Internal consistency reliability of the scales ranged from 0.74 to 0.94. Tests of clinical validity were significant in the hypothesized direction for the majority of scales for length of hospital stay, duration since the burn, percent of body surface area burned, overall clinician assessment of severity of burn injury, and number of comorbidities. The criterion validity of the instrument was supported using the Child Developmental Inventories for Burn Children in early childhood and preschool stages of development comparing normal vs abnormal children. The instrument was sensitive to changes over time following a clinical course observed by physicians in practice. The Health Outcomes Burn Questionnaire for Infants and Children 5 years of age and younger is a clinically based reliable and valid assessment tool that is sensitive to change over time for assessing burn outcomes in this age group.

Lack of Effect of Sleep on Energy Expenditure and Physiologic Measures in Critically Ill Burn Patients

OBJECTIVE Energy expenditure measurements, performed while patients are in standardized resting conditions, are often used as an indicator of care by which to evaluate the adequacy of nutrition support regimens. Little attention has been directed toward examining potential errors incurred by deriving daily energy needs based on a single 15- to 20-minute measurement. This study was designed to differentiate energy expenditure during periods of sleep (defined as time spent in any of the standard sleep stages) and wakefulness in pediatric burn patients. DESIGN Twenty-four-hour indirect calorimetry, polysomnography, and physiologic assessments (mean arterial pressure, heart rate, body temperature, oxygen saturation, and respiratory rate) were conducted simultaneously in 14 patients, who were thermally injured and tracheally intubated, for a total of 45 24-hour intervals. SUBJECTS Mean age of the patients was 10.8+/-1.2 years. Mean total body surface area of the injury was 55.7+/-4.7%, and mean full-thickness burn was 48.8+/-6.0%. STATISTICAL ANALYSES PERFORMED A nested general linear analysis of variance model was used to evaluate the association between sleep, wakefulness, and energy needs; adjustments were made for postburn day and multiple test runs per patient. RESULTS On average, subjects slept 699+/-46 minutes/day. They experienced a large number of awakenings from sleep (mean=53+/-6.3 awakenings per 24 hours). Patients had mean energy expenditure of 2,529+/-396 kcal/day while awake and 2,360+/-291 kcal/day while asleep, and these mean values did not differ significantly. No differences in physiologic measurements during the awake and sleep states were found. APPLICATIONS There appears to be little difference in the metabolism of seriously injured burn patients while asleep and while awake. The study deemphasizes the importance of performing indirect calorimetry at rest in critically ill pediatric burn patients, and it supports the extrapolation of daily energy expenditure from a 15- to 20-minute steady-state measurement obtained during either sleep or wakefulness.

A prospective analysis of serum vitamin K in severely burned pediatric patients.

Patients with burn injuries exhibit multiple risk factors for the development of vitamin K deficiency, including malabsorption, limited enteral intake, antibiotic therapy, and multiple surgical procedures. A prospective evaluation of 48 children was conducted to evaluate serum vitamin K values during the first 4 postburn weeks. Serum levels were analyzed in relation to clinical course. Days of antibiotic (p < 0.02) and albumin therapy (p < 0.003), percentage body surface area excised (p < 0.006), and the administration of blood products (p < 0.05) were significantly correlated with serum vitamin K levels, and days of diarrhea approached statistical significance (p < 0.06). No relationship was found between serum values and prothrombin time, activated partial thromboplastin time, or serum albumin. Ninety-one percent of the children demonstrated serum values below expected norms. These data suggest a relationship between coagulopathy and an intact functioning gastrointestinal tract. However, the relative importance of dietary versus endogenous vitamin K produced by intestinal bacteria remains to be elucidated.

Effect of ibuprofen on the postburn hypermetabolic response: a case report.

Severely burned patients exhibit a postburn hypermetabolic response which, with the most severe burns, can double the patients metabolic rate. We report on a 54-year-old man who was on long-term ibuprofen administration for treatment of arthritis before sustaining a 38% total body surface area burn. This patient failed to demonstrate the normal hypermetabolic response. The possibility that the ibuprofen administration prevented the hypermetabolic response is discussed.