Sarah J. Peterson

Intensive Nutrition in Acute Lung Injury A Clinical Trial (INTACT)

BACKGROUND Despite extensive use of enteral (EN) and parenteral nutrition (PN) in intensive care unit (ICU) populations for 4 decades, evidence to support their efficacy is extremely limited. METHODS A prospective randomized trial was conducted evaluate the impact on outcomes of intensive medical nutrition therapy (IMNT; provision of >75% of estimated energy and protein needs per day via EN and adequate oral diet) from diagnosis of acute lung injury (ALI) to hospital discharge compared with standard nutrition support care (SNSC; standard EN and ad lib feeding). The primary outcome was infections; secondary outcomes included number of days on mechanical ventilation, in the ICU, and in the hospital and mortality. RESULTS Overall, 78 patients (40 IMNT and 38 SNSC) were recruited. No significant differences between groups for age, body mass index, disease severity, white blood cell count, glucose, C-reactive protein, energy or protein needs occurred. The IMNT group received significantly higher percentage of estimated energy (84.7% vs 55.4%, P < .0001) and protein needs (76.1 vs 54.4%, P < .0001) per day compared with SNSC. No differences occurred in length of mechanical ventilation, hospital or ICU stay, or infections. The trial was stopped early because of significantly greater hospital mortality in IMNT vs SNSC (40% vs 16%, P = .02). Cox proportional hazards models indicated the hazard of death in the IMNT group was 5.67 times higher (P = .001) than in the SNSC group. CONCLUSIONS Provision of IMNT from ALI diagnosis to hospital discharge increases mortality.

The prevalence of sarcopenia in patients with respiratory failure classified as normally nourished using computed tomography and subjective global assessment.

BACKGROUND Declines in nutrition status and adverse body composition changes frequently occur in the critically ill. The objective of this cross-sectional study was to examine the prevalence of sarcopenia and its occurrence in patients classified as normal nourished using subjective global assessment (SGA). METHODS Exploiting diagnostic CT images, skeletal muscle mass at the L3 region was quantified and used to determine sarcopenia and its association with normal nutrition status in 56 patients with respiratory failure. Sarcopenia was defined as an L3 skeletal muscle index of ≤38.5 cm(2)/m(2) for women and ≤52.4 cm(2)/m(2) for men. CT imaging and SGA classifications completed within 14, 10 and 7 days of each other were analyzed to assess sarcopenia and the influence of time between scans on misclassification (ie, normal nourished and sarcopenic). Descriptive statistics were conducted. RESULTS The average patient was 59.2 (± 15.6) years old, admitted with sepsis/infection, an APACHE II score of 26 (± 8.0), and BMI of 28.3 (± 5.8). Sarcopenia and sarcopenic obesity were prevalent in a minimum of 56% and 24% of patients, respectively, depending on the number of days between CT imaging and SGA assessment. Misclassified individuals were predominantly male, minority and overweight or obese. Controlling for age, no significant differences were noted for patients classified as normal nourished vs malnourished by SGA for lumbar muscle cross-sectional, whole-body lean mass, or skeletal muscle index. CONCLUSIONS Sarcopenia is highly prevalent among patients with respiratory failure requiring mechanical ventilation (MV) and not readily detected in patients classified as normal nourished using SGA.

The Use of Prealbumin and C-Reactive Protein for Monitoring Nutrition Support in Adult Patients Receiving Enteral Nutrition in an Urban Medical Center

BACKGROUND Serum prealbumin (PAB) is commonly used to assess protein status and is often used to monitor the response to nutrition support. However, during inflammation, the liver synthesizes acute-phase proteins such as C-reactive protein (CRP) at the expense of PAB. OBJECTIVE The purpose of this retrospective study was to determine whether changes in PAB reflect the delivery of adequate nutrients or changes in inflammatory status in hospitalized adults (≥18 years) receiving enteral nutrition (n = 154). METHODS Protein and energy intake were compared to changes in PAB, assessed at baseline and twice weekly. C-reactive protein was assessed when PAB was <18 mg/dL to determine the presence and severity of inflammation. RESULTS In a sample of mostly critically ill patients, there was no significant difference in change in PAB for those receiving ≥60% of calorie needs (2.74 ± 9.50 mg/dL) compared to <60% of calorie needs (2.48 ± 9.36 mg/dL; P = .86). Changes in PAB correlated only with changes in CRP (r = -0.544, P < .001). In a subgroup analysis of 62 patients with repeated measures of PAB and CRP, PAB increased significantly only in the bottom 2 tertiles for calorie delivery and the lowest tertile for protein delivery. CONCLUSIONS These results indicate that PAB may not be a sensitive marker for evaluating the adequacy of nutrition support in critically ill patients with inflammation. Only change in CRP was able to significantly predict changes in PAB, suggesting that an improvement in inflammation, rather than nutrient intake, was responsible for the increases in PAB levels.

Nutrition assessment: The reproducibility of subjective global assessment in patients requiring mechanical ventilation

Background/Objectives:The detection of malnutrition in the intensive care unit (ICU) is critical to appropriately address its contribution on outcomes. The primary objective of this investigation was to determine if nutritional status could be reliably classified using subjective global assessment (SGA) in mechanically ventilated (MV) patients.Subjects/Methods:Fifty-seven patients requiring MV >48 h in a university-affiliated medical ICU were evaluated in this cross-sectional study over a 3-month period. Nutritional status was categorized independently by two registered dietitians using SGA. Frequencies, means (+ s.d.), χ 2 and t-tests were used to describe the population characteristics; agreement between raters was evaluated using the κ statistic.Results:On admission, the average patient was 50.4 (±14.2) years of age, overweight (body mass index: 29.0±9.2kg/m2), had an acute physiology and chronic health evaluation II score of 24 (±10) and respiratory failure. Fifty percent (n=29) of patients were categorized as malnourished. Agreement between raters was 95% before consensus, reflecting near perfect agreement (κ=0.90) and excellent reliability. Patients categorized as malnourished were more often admitted to the hospital floor before the ICU (n=32; 56%), reported decreased dietary intake (69 vs 46%, P=0.02) and exhibited signs of muscle wasting (45 vs 7%, P<0.001, respectively) and fat loss (52 vs 7%, P<0.001, respectively) on physical exam when compared with normally nourished individuals.Conclusions:SGA can serve as a reliable nutrition assessment technique for detecting malnutrition in patients requiring MV. Its routine use should be incorporated into future studies and clinical practice.

Prevalence of Sarcopenia and Associated Outcomes in the Clinical Setting

Sarcopenia refers to age-associated decrease in muscle mass and function. The condition was originally described in the elderly, but emerging evidence suggests that it is also a concern among the chronically ill nonelderly. Currently there are a number of definitions for diagnosing sarcopenia; however, in the clinical setting, abdominal computed tomography (CT) scans completed for diagnostic purposes can be utilized to identify CT-defined sarcopenia. Recent studies suggest that prevalence of CT-defined sarcopenia is high among chronically ill patients, ranging from 15%-50% in patients with cancer, 30%-45% with liver failure, and 60%-70% for critically ill patients in the intensive care unit. Depleted muscle mass is associated with infectious complications, prolonged duration of mechanical ventilation, longer hospitalization, greater need for rehabilitation care after hospital discharge, and higher mortality. In consideration of the growing population of older adults with multiple comorbidities, more research is needed to identify sarcopenia and develop interventions that are directed at attenuating or reversal muscle loss.

Use of 3 Tools to Assess Nutrition Risk in the Intensive Care Unit

BACKGROUND Identifying patients at nutrition risk proves difficult in the intensive care unit (ICU) due to the nature of critical illness. No consensus exists on the most appropriate method to identify these patients. Traditional screens and assessments are often limited due to their subjective nature. The purpose of the quality improvement project was to compare proportions of ICU patients deemed at nutrition risk using 3 different tools. MATERIAL AND METHODS A convenience sample of 294 patients admitted to the ICU was used. Patients were assessed using the institutions routine nutrition screening method, the Subjective Global Assessment (SGA), and the NUTrition Risk in Critically ill (NUTRIC) score. Information was collected on demographics, severity of illness, hospital and ICU length of stay (LOS), and disposition. Descriptive statistics were used to examine counts/proportions of risk categories; means ± SD were used to summarize demographic and clinical variables. RESULTS A total of 139 patients (47%) were deemed at nutrition risk or malnourished by at least 1 tool. Patients identified were older and had a lower body mass index, more weight loss, more fat and muscle wasting, more fluid accumulation, and lower average handgrips than those not at nutrition risk; they also had longer hospital and ICU LOS, higher rates of requiring further rehabilitation upon discharge, and higher mortality during hospitalization. CONCLUSION Traditional screening and assessment tools did not uniformly identify patients as malnourished or at nutrition risk in the ICU and therefore may be inappropriate for use in this population. Inclusion of physical assessment, functional status, and severity of illness may be useful in predicting nutrition risk in the ICU.

Exploitation of diagnostic computed tomography scans to assess the impact of nutrition support on body composition changes in respiratory failure patients.

BACKGROUND Assessment of nutritional status in intensive care unit (ICU) patients is limited. Computed tomography (CT) scans that include the first to fifth lumbar region completed for diagnostic purposes measures fat and lean body mass (LBM) depots and are frequently done in ICU populations and can be used to quantify fat and LBM depots. The purpose of this study was to assess if these scans could measure change in skeletal muscle (SKT), visceral adipose (VAT), and intermuscular adipose (IMAT) tissue and to examine the association between the amount of energy and protein received and changes in these depots. METHODS Cross-sectional area of SKT, VAT, and IMAT from CT scans at the third lumbar region was quantified at 2 time points (CT1 and CT2). Change scores between CT1 and CT2 for each of these depots and the percentage of estimated energy/protein needs received were determined in 33 adults that with acute respiratory failure. Descriptive statistics and multiple regression was used to evaluate the influence of baseline characteristics and the percentage energy/protein needs received between CT1 and CT2 on percentage change/day between CT1 and CT2 on SKM, IMAT, and VAT. RESULTS Participants were on average (SD) 59.7 (16) years old, received 41% of energy and 57% of protein needs. The average time between CT1 and CT2 was 10 (5) days. SKM declined 0.49%/day (men P = .07, women P = .09) and percentage of energy needs received reduced loss (β = 0.024, P = .03). No change in VAT or IMAT occurred. CONCLUSIONS CT scans can be exploited to assess change in body composition in ICU patients and may assist in detecting the causal link between nutritional support and outcomes in future clinical trials.

Enteral Nutrition Formulas: Which Formula Is Right for Your Adult Patient?

In the last few decades, there has been tremendous advancement in the area of enteral nutrition formulas. Enteral nutrition makes it possible to provide important substrates for those who cannot or will not meet daily requirements via oral intake but who have an intact digestive system. Numerous enteral nutrition formulas are currently available, with a large portion of them targeting specific disease conditions, thus making it a daunting task at times for a clinician to sort through all the possibilities and decide on the most appropriate formula. This review provides a close examination of various enteral formula categories and presents proposed mechanisms of specialized ingredients, followed by a thorough evidence-based analysis of existing literature before making recommendations for the various enteral formula categories.

Prevalence and characteristics of adult-onset food allergy

Food allergy has been estimated to affect nearly 5% of adults and 8% of children, and to be increasing in prevalence. Our understanding of the prevalence and characteristics of food allergy, particularly to the major food allergens of peanut, tree nut, egg, milk, fish, shellfish, wheat, and soy, have been largely built from studies of food allergy in children and infants: however, less is known about food allergy in adults. Although it is common for childhood food allergies to milk, egg, soy, or wheat to be outgrown, those to fish or shellfish have been suggested to develop in adulthood and/or to persist. Indeed, in a previous large, random, telephone-based study focused specifically on seafood and fish allergy in the United States, 60% and 39% of these respective allergies were ascribed to developing in adulthood rather than during childhood. Here, our primary objective was to determine the prevalence of adult-onset food allergy, with secondary objectives of examining the characteristics of these patients further, including the assessment of additional common allergens. By using the Northwestern Medicine Enterprise Data Warehouse, medical records of patients who were seen by allergy physicians at the Northwestern University adult allergy clinics and who received a diagnosis of food allergy (based on

Validation of Bedside Ultrasound of Muscle Layer Thickness of the Quadriceps in the Critically Ill Patient (VALIDUM Study): A Prospective Multicenter Study.

Background: In critically ill patients, muscle atrophy is associated with long-term disability and mortality. Bedside ultrasound may quantify muscle mass, but it has not been validated in the intensive care unit (ICU). Here, we compared ultrasound-based quadriceps muscle layer thickness (QMLT) with precise quantifications of computed tomography (CT)–based muscle cross-sectional area (CSA). Methods: Patients ≥18 years old with abdominal CT scans performed for clinical reasons were recruited from 9 ICUs for an ultrasound assessment of the quadriceps. CT scans of the third lumbar vertebra, performed <24 hours before or <72 hours after ICU admission, were analyzed for CSA. Low muscularity was defined as 170 cm2 for men and 110 cm2 for women. The ultrasound probe was maximally compressed against the skin and QMLT was measured on 2 sites of each quadriceps <72 hours of the CT scan. Results: Mean CT-derived muscle CSA was 109 ± 25 cm2 for women and 168 ± 37 cm2 for men, where 58% of patients exhibited low muscularity; only 2.7% patients were underweight according to body mass index. QMLT was positively correlated with CT CSA (r = 0.45, P < .001). Based on logistic regression to predict low muscularity, QMLT independently generated a concordance index (c) of 0.67 (P < .002), which increased to 0.77 (P < .001) when age, sex, body mass index, Charlson Comorbidity Index, and admission type (surgical vs medical) were added. Conclusions: Our results suggest that QMLT alone with our current protocol may not accurately identify patients with low muscle mass.