Carol Ireton-Jones

Equations for the Estimation of Energy Expenditures in Patients with Burns with Special Reference to Ventilatory Status

There are advantages to the use of easily assessed variables for the prediction of energy expenditures of patients with burns. The purpose of this study was to determine whether height, age, sex, weight, ventilatory status, and diagnosis could be correlated with measured energy expenditures of hospitalized patients. With the use of data from 200 patients, stepwise, multivariate regression analysis derived the following equations: EEE(v) = 1925 - 10(A) + 5(W) + 281(S) + 292(T) + 851(B) (R2 = 0.43); EEE(s) = 629 - 11(A) + 25(W) - 609(O) (R2 = 0.50); where EEE = estimated energy expenditure (kcal/day), v = ventilatory dependency, s = spontaneously breathing, A = age (yr), W = body weight (kg), S = sex (male = 1, female = 0), diagnosis of T = trauma, B = burn, O = obesity present = 1, absent = 0). The equations were tested on 100 patients. Measured energy expenditures were not significantly different from calculated EEE(s) or EEE(v) (paired t test, p greater than 0.25). Energy expenditures can be accurately estimated in a variety of patients, including those with major burns with the use of easily attained information.

Obesity: Nutrition Support Practice and Application to Critical Care

Much controversy exists regarding the nutritional care of obese, hospitalized patients. There is no real agreement among health care professionals in the nutritional support of obese patients. A survey was designed to determine the methods used to provide for the nutritional needs of obese, hospitalized patients. The survey included questions on definition of obesity, equations used to calculate energy and protein needs, and body weight used for calculations. The information received from this survey describes the variability of nutritional care for obese, hospitalized patients. In addition, a review of the current literature is provided regarding the metabolic response of the obese.

Predicting energy needs in obese patients.

Obesity has become an epidemic in the United States, with other western countries also reporting increases in incidence of obesity. With many associated comorbidities, it is the most common nutritional disorder facing the medical team. However, the assessment of macronutrient needs for nutrition support regimens in obese adults is controversial. This review summarizes existing research on popular predictive approaches, including the Harris-Benedict equation, kilocalories per kilogram, and the Ireton-Jones equations. Complications including special considerations for patients who have undergone bariatric surgeries and current evidence on hypocaloric regimens are also discussed.

Adjusted body weight, con : Why adjust body weight in energy-expenditure calculations?

Evaluation of energy requirements of normal individuals and hospitalized patients is most often accomplished using an energy equation. Energy equations attempt to measure resting metabolic rate (RMR), the largest factor in total daily energy expenditure. Components of most energy equations include height, weight, age, and gender. These factors are related to energy expenditure; however, each factor has individual characteristics that affect energy expenditure. Body weight is a major factor in RMR and total daily energy expenditure. For obese individuals, estimation of energy expenditure may be a challenge due to the increased body weight. Therefore, some equations attempt to minimize the effect of body weight on energy expenditure assessment by adjusting the obese individuals body weight. Data do not support adjustment of body weight in normal individuals. In hospitalized patients, there are several equations that are used to estimate energy expenditure of obese patients, which include adjusting the body weight and modifying the overall energy requirements. Measurement of RMR can obviate the need for estimating energy expenditure. It is important to evaluate any energy-expenditure equation that is used to estimate energy needs in normal people and hospitalized patients before applying it to patient care.

Clinical Pathways in Home Nutrition Support

In home-care settings, physicians with various medical specialties may order home enteral and/or parenteral nutrition support. Clinical pathways may be used to provide a clear, concise, standardized method for ordering and monitoring home nutrition support. The clinical pathways should be appropriate for 80% of the patients placed on the pathways, allowing for a 20% variance, or deviation, from the pathway. In one home-care facility, disease-specific clinical pathways have been used for longer than 1 year for patients with a variety of diseases requiring home nutrition support. To determine the usefulness of the home nutrition support clinical pathways, data obtained from 20 patients were analyzed. Patients were followed up while being treated using home nutrition support clinical pathways designed for oncology (9 patients), human immunodeficiency virus/acquired immunodeficiency syndrome (2 patients), short bowel syndrome (6 patients), and hyperemesis (3 patients) for 191 weeks. Overall, an average variance (deviation from the pathway) of 22% (the number of variances divided by the total weeks of therapy) was observed. The use of the pathways to provide enteral or parenteral nutrition facilitated more cost-effective care by following pathway guidelines for obtaining laboratory values and patient visits. Communication between the home-care staff and the physician was also improved. Clinical pathways can enable standardization of care for patients receiving nutrition support at home.

Characteristics of a Cohort of Home Parenteral Nutrition Patients at the Time of Enrollment in the Sustain Registry

BACKGROUND Home parenteral nutrition (HPN) is a vital lifesaving therapy for patients who are unable to maintain weight, fluid balance, nutrition, and functional status via oral or enteral nutrition alone. There are few current data sources describing HPN prevalence, patient demographics, or long-term outcomes in the United States. OBJECTIVE To describe demographics and baseline characteristics of patients receiving HPN therapy. METHODS This is a descriptive analysis of data from the first cohort of HPN patients at time of enrollment in the SustainTM Registry between August 2011 and February 2014. RESULTS There were 1251 patients enrolled from 29 sites. Eighty-five percent of patients were adults, with a mean age of 51.3 ± 15.3 years. Fifteen percent were pediatric, with a mean age of 4.9 ± 4.9 years. For both age groups, short-bowel syndrome was the most frequently reported HPN indication (24%). Adults most commonly had a peripherally inserted central catheter (47%) or a tunneled catheter (43%) for HPN administration. In contrast, most pediatric patients (72%) had a tunneled catheter. Most patients received parenteral nutrition daily and consumed some oral nutrition. Twenty-eight percent of all patients were expected to require HPN indefinitely. CONCLUSIONS This is the first report of descriptive data from the Sustain Registry. The data reveal important characteristics of patients receiving HPN in 29 U.S. sites.

The effect of burn wound excision on measured energy expenditure and urinary nitrogen excretion

The effect of wound closure on the metabolic response to burn injury is uncertain. Energy expenditures were measured in 20 patients by indirect calorimetry (MEE) and estimated initially by the Curreri formula (CEE) and subsequently by a modification of the Curreri formula (MCEE), adjusted for changes in open wound size and body weight. Urinary urea nitrogen (UUN) excretions were measured over 24 hours. Second- and third-degree burns, initially involving 31% to 74% of the body surface areas, were reduced in size to less than 15% by excisions and grafting procedures. The correlations among percentage open wounds, MEEs, CEEs, and MCEEs were low. UUN excretions were not correlated with percentage open wounds or with MEEs. Estimates of energy expenditures using the Curreri formula appear to be of limited usefulness in prescribing caloric intakes in burned patients. Serial UUNs are useful in determining protein requirements, but were not correlated with MEEs or with the extent of open wounds.

Management of the Home Parenteral Nutrition Patient

Parenteral nutrition (PN) support can be managed in the home setting for both a short-term and long-term period or for a lifetime, permitting individuals who cannot adequately absorb nutrients enterally to achieve a normal lifestyle. Nutrition support professionals must be aware of home PN (HPN) management principles before discharge to ensure a smooth transition to home with all requisite monitoring. This article will discuss the initiation and monitoring of patients on HPN, the prevention and treatment of potential complications, the contributions of the home infusion provider, and the home nutrition support team and the outcomes of HPN.

Resting Energy Expenditures Measured by Indirect Calorimetry are Higher In Preadolescent Children with Cystic Fibrosis than Expenditures Calculated from Prediction Equations

OBJECTIVE This study compared measured resting energy expenditures to resting energy expenditures calculated using Harris-Benedict equations (HBEs) and the Cystic Fibrosis Consensus Committee equations (CFCCEs). DESIGN We studied 31 preadolescent boys and girls with cystic fibrosis who ranged in age from 3.25 to 12.75 years old. The patients were afebrile and not in pulmonary distress. Measured resting energy expenditures were determined using a portable metabolic measurement cart with fully automated calibration and data management. The measured resting energy expenditures obtained were compared with values obtained using HBEs and CFCCEs. RESULTS For each patient, the measured resting energy expenditure value was above the predicted resting energy expenditure values derived from HBEs (P < or = .0001) and CFCCEs (P < or = .01). APPLICATIONS The HBEs and the CFCCEs underestimated the energy expenditures of the study population by 13% and 8%, respectively. These findings support the usefulness of the measurement of energy expenditures in determining the energy needs of preadolescent patients with cystic fibrosis. In clinical practice, the resting energy expenditures would be multiplied by activity coefficients to determine the total daily energy expenditures of this population.

Can we justify continued interest in indirect calorimetry

ture predicted by 7 separate equations. 1 The paper represents a retrospective review of a relatively small (52 cases over 5 years) heterogenous mix of patients. Over 200 predictive equations have been published. 2 The criteria for selection of the 7 used is not clear. Their study again demonstrated the shortcomings of predictive equations in managing the individual critically ill child. Problems encountered in using the equations to predict energy expenditure are outlined in Table 1. For an equation to be effective, it must be used as formulated. As pointed out by Van Way, 3 33% of the published versions of the Harris-Benedict equations that he reviewed were different from the original. These erroneous versions of the Harris-Benedict equations produced results as much as 55% different from the original equation. 3 Table 2 shows our own observations in reviewing recent editions of Cecil’s Textbook of Medicine. The constant for women is correct in only 1 of the last 5 editions. In 3 editions, using the version from Cecil would result in estimates of caloric expenditure approximately 600 kcal/d less than using the original equation. It is difficult to know all the mechanisms responsible for generating these aberrant equations, but the frequency suggests that factors in addition to simple typographical errors may be involved. In the use of