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Metabolic rate is generally assessed by use of equations in critically ill patients, but evidence pertaining to the validity of these equations in this population has not been systematically evaluated. This paper represents the first such systematic analysis in adult patients. A work group created by the American Dietetic Association identified pertinent peer-reviewed articles. The work group systematically evaluated these articles and formulated conclusion statements and grades based on the available evidence. Seven equations plus the Fick method were found to have validation work that met criteria for inclusion in this analysis. The Harris-Benedict equation with and without modifiers had the most validation work behind it (n=13), followed by Ireton-Jones (1992 and 1997) (n=9), Penn State (1998, 2003) (n=2), and Swinamer (n=1). Five studies pertaining to the Fick method met acceptance criteria. Based on these validation studies, the Harris-Benedict, Ireton-Jones 1997, and Fick methods can be confidently eliminated from use in assessment of energy expenditure in critically ill patients. The Penn State 2003, Swinamer, and Ireton-Jones 1992 equations may be useful in critically ill nonobese patients, whereas the Ireton-Jones 1992 and Penn State 1998 equations seem to be useful in obese patients. The strength of these conclusions is moderated because of limited and sometimes inconsistent data. More validation work is needed to confirm and increase the strength of these conclusions.

Objective To evaluate the accuracy of seven predictive equations, including the Harris-Benedict and the Mifflin equations, against measured resting energy expenditure (REE) in hospitalized patients, including patients with obesity and critical illness. Design A retrospective evaluation using the nutrition support service database of a patient cohort from a similar timeframe as those used to develop the Mifflin equations. Subjects/Setting All patients with an ordered nutrition assessment who underwent indirect calorimetry at our institution over a 1-year period were included. Intervention Available data was applied to REE predictive equations, and results were compared to REE measurements. Main Outcome Measures Accuracy was defined as predictions within 90% to 110% of the measured REE. Differences >10% or 250 kcal from REE were considered clinically unacceptable. Statistical Analyses Performed Regression analysis was performed to identify variables that may predict accuracy. Limits-of-agreement analysis was carried out to describe the level of bias for each equation. Results A total of 395 patients, mostly white (61%) and African American (36%), were included in this analysis. Mean age±standard deviation was 56±18 years (range 16 to 92 years) in this group, and mean body mass index was 24±5.6 (range 13 to 53). Measured REE was 1,617±355 kcal/day for the entire group, 1,790±397 kcal/day in the obese group (n=51), and 1,730±402 kcal/day in the critically ill group (n=141). The most accurate prediction was the Harris-Benedict equation when a factor of 1.1 was multiplied to the equation (Harris-Benedict 1.1), but only in 61% of all the patients, with significant under- and overpredictions. In the patients with obesity, the Harris-Benedict equation using actual weight was most accurate, but only in 62% of patients; and in the critically ill patients the Harris-Benedict 1.1 was most accurate, but only in 55% of patients. The bias was also lowest with Harris-Benedict 1.1 (mean error −9 kcal/day, range +403 to −421 kcal/day); but errors across all equations were clinically unacceptable. Conclusions No equation accurately predicted REE in most hospitalized patients. Without a reliable predictive equation, only indirect calorimetry will provide accurate assessment of energy needs. Although indirect calorimetry is considered the standard for assessing REE in hospitalized patients, several predictive equations are commonly used in practice. Their accuracy in hospitalized patients has been questioned. This study evaluated several of these equations, and found that even the most accurate equation (the Harris-Benedict 1.1) was inaccurate in 39% of patients and had an unacceptably high error. Without knowing which patient's REE is being accurately predicted, indirect calorimetry may still be necessary in difficult to manage hospitalized patients.

The objective of this study was to evaluate the evidence behind specific but common patient care decisions in support of enteral feedings for patients admitted to intensive care units. Six specific questions were developed and refined to address clinical outcomes specific to clinical practice decisions pertinent to enteral feeding of critically ill patients. The data sources consisted of an intensive literature review from five databases, using standardized search terms. Randomized controlled clinical trials, meta-analyses, consensus statements, reviews, US Food and Drug Administration alerts, and case reports were selected for study. Research reports were abstracted in detail and evaluated for research quality using the criteria developed by the American Dietetic Association. Consensus statements regarding the influence of specific enteral feeding methods on key clinical outcomes (ie, infectious complications, cost, length of hospital stay, and mortality) were developed and graded based on the quality of the available evidence. The data support the use of enteral over parenteral nutrition to reduce infectious complications and cost, and the initiation of enteral feedings within 24 to 48 hours of injury or admission to an intensive care unit to reduce infectious complications and length of hospital stay in head injury and trauma patients. Postpyloric tube placement is associated with reduced gastric residual volume and reflux, but adequately powered trials are not available to support prevention of aspiration pneumonia. Acceptance of gastric residual volumes of up to 250 mL may increase volume of formula delivered. Promotility agents are associated with reduced gastric residual volume. Feeding patients in the semirecumbent rather than supine position is associated with reduced aspiration pneumonia and pharyngoesophageal formula reflux. Actual delivery of 14 to 18 kcal/kg/day or 60% to 70% of goal is associated with improved outcomes, whereas greater intake may not be in some populations. Blue food coloring should not be used with enteral feedings due to its limited sensitivity for aspiration and some risk of mortality. Well-designed, adequately powered, randomized controlled clinical trials are needed to evaluate any benefit of tube tip position on aspiration pneumonia or mortality, and of early enteral feedings on mortality.

Several factors may alter apparent resting metabolic rate (RMR) during measurement with indirect calorimetry. Likewise, numerous indirect calorimetry measurement protocols have been developed over the years, and the methodology employed could influence test results. As part of a larger project to determine the role of indirect calorimetry in clinical practice, a systematic review of the literature was undertaken to determine the ideal subject condition and test methodology for obtaining reliable measurement of RMR with indirect calorimetry. Food, ethanol, caffeine, and nicotine affect RMR for a variable number of hours after consumption; therefore, intake of these items must be controlled before measurement. Activities of daily living increase metabolic rate, but a short rest (≤20 minutes) before testing is sufficient for the effect to dissipate. Moderate or vigorous physical activity has a longer carryover effect and therefore must be controlled in the hours before a measurement of RMR is attempted. Limited data were found regarding ideal ambient conditions for RMR testing. Measurement duration of 10 minutes with the first 5 minutes deleted and the remaining 5 minutes having a coefficient of variation

Background An assessment of energy needs is a necessary component in the development and evaluation of a nutrition care plan. The metabolic rate can be measured or estimated by equations, but estimation is by far the more common method. However, predictive equations might generate errors large enough to impact outcome. Therefore, a systematic review of the literature was undertaken to document the accuracy of predictive equations preliminary to deciding on the imperative to measure metabolic rate. Methods As part of a larger project to determine the role of indirect calorimetry in clinical practice, an evidence team identified published articles that examined the validity of various predictive equations for resting metabolic rate (RMR) in nonobese and obese people and also in individuals of various ethnic and age groups. Articles were accepted based on defined criteria and abstracted using evidence analysis tools developed by the American Dietetic Association. Because these equations are applied by dietetics practitioners to individuals, a key inclusion criterion was research reports of individual data. The evidence was systematically evaluated, and a conclusion statement and grade were developed. Results Four prediction equations were identified as the most commonly used in clinical practice (Harris-Benedict, Mifflin-St Jeor, Owen, and World Health Organization/Food and Agriculture Organization/United Nations University [WHO/FAO/UNU]). Of these equations, the Mifflin-St Jeor equation was the most reliable, predicting RMR within 10% of measured in more nonobese and obese individuals than any other equation, and it also had the narrowest error range. No validation work concentrating on individual errors was found for the WHO/FAO/UNU equation. Older adults and US-residing ethnic minorities were underrepresented both in the development of predictive equations and in validation studies. Conclusions The Mifflin-St Jeor equation is more likely than the other equations tested to estimate RMR to within 10% of that measured, but noteworthy errors and limitations exist when it is applied to individuals and possibly when it is generalized to certain age and ethnic groups. RMR estimation errors would be eliminated by valid measurement of RMR with indirect calorimetry, using an evidence-based protocol to minimize measurement error. The Expert Panel advises clinical judgment regarding when to accept estimated RMR using predictive equations in any given individual. Indirect calorimetry may be an important tool when, in the judgment of the clinician, the predictive methods fail an individual in a clinically relevant way. For members of groups that are greatly underrepresented by existing validation studies of predictive equations, a high level of suspicion regarding the accuracy of the equations is warranted.

The Dietitians in Nutrition Support dietetic practice group of The American Dietetic Association administered a questionnaire to evaluate changes in nutrition support services provided to hospitalized patients and home patients in 1989 and compared the results with results of a survey administered in 1986. The 1986 survey documented an increase in tube feeding to inpatients during 1984 to 1986 and greater dietitian staffing in tertiary care hospitals than in primary care hospitals and in larger hospitals in 1986. The 1989 questionnaire was mailed to clinical nutrition managers from a nationwide random sample of 1,000 hospitals from American Hospital Association members; 271 responses were received. Full-time equivalent (FTE) registered dietitians (RDs)--including clinical RDs, nutrition support service RDs, and clinical nutrition managers--decreased 11% from 1986 to 1989. FTE dietetic technicians decreased 22%. The number of FTE nutrition support service RDs and clinical nutrition managers decreased significantly (P less than .05). The mean number of FTE clinical dietitians per 100 beds decreased from 1.4 to 1.0 from 1986 to 1989. These decreases in dietetics staffing occurred despite an overall increase in total hospital FTE staff of 2.9%. Reported daily provision of nutrition support modalities to inpatients was 3.5% for parenteral nutrition, 4.9% for enteral tube feeding, and 9.6% for oral supplements. Decreased dietetics staffing was accompanied by other factors that negatively affect productivity (and therefore ability to provide adequate patient care), including inadequate delegation of technical tasks to dietetic technicians, limited availability of secretarial and computer support, and minimal provision of pocket pagers. These trends may be evidence of inadequacy of dietetics staffing to meet the needs of the US population for nutrition care.

Changes in hospital funding resulting from the Prospective Payment System have been recognized as a major force in hospitals in the 1980s. The Dietitians in Nutrition Support (DNS) Practice Group examined these changes using a survey sent to 1,000 clinical nutrition managers at American Hospital Association (AHA) hospitals. The goals of the survey were (a) to evaluate changes in billing for nutrition services and (b) to evaluate changes in resources available to dietetics staff members. Although income from nutrition services to inpatients had increased only 18% since 1984, 45% of respondents reported an increase in payment for outpatient services. Prior to 1984, larger hospitals reported screening for malnutrition more often than smaller hospitals, and the responsibility for screening was handled more often by dietetic technicians than by RDs. Larger hospitals also reported establishment of a home nutrition support company more often than smaller hospitals. Computer and academic course costs were paid more frequently by nonprofit and tertiary hospitals. Although the number of hospitals billing for nutrition services to patients was small, most reported receiving payment. We conclude that charges for nutrition services by dietitians to outpatients have increased, and that most dietitians who bill for services receive payment. Academic and technological resources for RDs have increased in general, though smaller primary-care and for-profit hospitals report such supports less consistently than larger, tertiary-care, and not-for-profit hospitals.

Reports of the economic impact of diagnosis-related group funding on staffing and patient care in hospitals have varied from optimistic to bleak. The Dietitians in Nutrition Support Practice Group of The American Dietetic Association developed a questionnaire to evaluate changes in nutrition support services provided to inpatients and home patients between 1984 and 1986. The written survey instrument was mailed toclinical nutrition managers at a nationwide random selection of 1,000 hospital members ofthe American Hospital Association. Two hundred thirty-six responses were received. Respondents reported an increase in the use of enteral nutrition support for inpatients between1984 and 1986. In 1986, tertiary-care hospitals also reported greater use of parenteral nutrition support and tube feeding for inpatients and home patients than did primary-care hospitals. Tertiary-care hospitals also reported higher staffing in 1986 than did primary-care hospitals in the following areas: clinical, nutrition support, and outpatient dietitians and dietetic technicians. Greater use of enteral and parenteral support for inpatients was noted by large hospitals as well as greater staffing in the following areas: clinical managers; nutrition support, clinical, outpatient, and home care dietitians; and dietetic technicians. However, the ratio of patients to RDs was greater in large than in small hospitals. There was no significant difference in patient:RD ratio between tertiary-care and primary-care hospitals. The only difference between responses from for-profit and nonprofit hospitals was in the number of nutrition support RD positions, which was largerin the nonprofit hospitals. Utilization of nutrition support for inpatients or home patients was not different for hospitals in different profit categories.J Am Diet Assoc 89:1452-1457, 1989.