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BACKGROUND AND AIMS: Indirect calorimetry (IC) is the gold standard for determining energy expenditure in patients requiring mechanical ventilation. Metabolic armbands using data derived from dermal measurements have been proposed as an alternative to IC in healthy subjects, but their utility during critical illness is unclear. The aim of this study was to determine the level of agreement between the SenseWear armband and the Deltatrac Metabolic Monitor in mechanically ventilated intensive care unit (ICU) patients. METHODS: Adult ICU patients requiring invasive ventilator therapy were eligible for inclusion. Simultaneous measurements were performed with the SenseWear Armband and Deltatrac under stable conditions. Resting energy expenditure (REE) values were registered for both instruments and compared with Bland-Altman plots. RESULTS: Forty-two measurements were performed in 30 patients. The SenseWear Armband measured significantly higher REE values as compared with IC (mean bias, 85 kcal/24 h; P = .027). Less variability was noted between individual SenseWear measurements and REE as predicted by the Harris-Benedict equation (2 SD, ±327 kcal/24 h) than when IC was compared with SenseWear and Harris-Benedict (2 SD, ±473 and ±543 kcal/24 h, respectively). CONCLUSIONS: The systematic bias and large variability of the SenseWear armband when compared with gas exchange measurements confer limited benefits over the Harris Benedict equation in determining caloric requirements of ICU patients.
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Metabolismo Basal , Calorimetría Indirecta , Unidades de Cuidados Intensivos , Monitoreo Fisiológico/instrumentación , Anciano , Índice de Masa Corporal , Enfermedad Crítica/terapia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Respiración ArtificialRESUMEN
INTRODUCTION: Evidence behind the recommendations for protein feeding during critical illness is weak. Mechanistic studies are needed to elucidate the effects of amino acid and/or protein supplementation on protein metabolism before larger clinical trials with higher levels of protein feeding are initiated. METHODS: We studied the effects of parenteral amino acid supplementation (equivalent to 1 g/kg/day) over the course of 3 hours on whole-body protein turnover in critically ill patients in the intensive care unit (ICU) during the first week after admission. Patients were studied at baseline during ongoing nutrition and during extra amino acid supplementation. If the patient was still in the ICU 2 to 4 days later, these measurements were repeated. Protein kinetics were measured using continuous stable isotope-labeled phenylalanine and tyrosine infusions. RESULTS: Thirteen patients were studied on the first study occasion only, and seven were studied twice. Parenteral amino acid supplementation significantly improved protein balance on both occasions, from a median of -4 to +7 µmol phenylalanine/kg/hr (P =0.001) on the first study day and from a median of 0 to +12 µmol phenylalanine/kg/hr (P =0.018) on the second study day. The more positive protein balance was attributed to an increased protein synthesis rate, which reached statistical significance during the first measurement (from 58 to 65 µmol phenylalanine/kg/hr; n =13; P =0.007), but not during the second measurement (from 58 to 69 µmol phenylalanine/kg/hr; n =7; P =0.09). Amino acid oxidation rates, estimated by phenylalanine hydroxylation, did not increase during the 3-hour amino acid infusion. A positive correlation (r =0.80; P <0.0001) was observed between total amino acids and/or protein given to the patient and whole-body protein balance. CONCLUSION: Extra parenteral amino acids infused over a 3-hour period improved whole-body protein balance and did not increase amino acid oxidation rates in critically ill patients during the early phase (first week) of critical illness.
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Enfermedad Crítica/terapia , Fenilalanina/administración & dosificación , Proteínas/metabolismo , Aminoácidos/sangre , Nutrición Enteral , Femenino , Humanos , Infusiones Parenterales , Unidades de Cuidados Intensivos , Masculino , Persona de Mediana Edad , Proyectos PilotoRESUMEN
BACKGROUND & AIMS: Indirect calorimetry is the gold standard in determining energy expenditure to dose nutritional therapy for critically ill patients. The most commonly used system for indirect calorimetry in the ICU setting (Deltatrac Metabolic Monitor) is no longer in production. The aim of this study was to compare two new instruments for IC (Quark RMR, CCM Express) to the Deltatrac in mechanically ventilated patients. METHODS: Sequential measurements with all three instruments were performed in randomized order on 24 mechanically ventilated ICU patients. Resting energy expenditure (REE), respiratory quotient (RQ), oxygen consumption and carbon dioxide production were recorded during a stable 10-30 min period. RESULTS: There was no difference in mean REE measurements between Deltatrac, 1749 ± 389 kcal/24 h and Quark RMR, 1788 ± 494 kcal/24 h (P = 0.166). CCM Express produced 64% higher mean REE values (2876 ± 656 kcal/24 h) than Deltatrac (P < 0.0001). All instruments registered different values for RQ and expiratory minute volume. CONCLUSION: Available instruments for indirect calorimetry give conflicting estimates of energy expenditure in mechanically ventilated patients. Whilst the Quark RMR compares better with the Deltatrac than CCM Express, the mechanisms behind this difference needs to be further explored.
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Metabolismo Basal , Calorimetría Indirecta/instrumentación , Consumo de Oxígeno , Intercambio Gaseoso Pulmonar , Respiración Artificial , Adulto , Anciano , Índice de Masa Corporal , Dióxido de Carbono/metabolismo , Femenino , Hospitales Universitarios , Humanos , Unidades de Cuidados Intensivos , Masculino , Ensayo de Materiales , Persona de Mediana Edad , Proyectos Piloto , Reproducibilidad de los Resultados , Respiración , SueciaRESUMEN
OBJECTIVE: To examine whether emotional memory (EM) of objects with self-reference in Alzheimer's disease (AD) can be modeled with binomial logistic regression in a free recall and an object recognition test to predict EM enhancement. METHOD: Twenty patients with AD and twenty healthy controls were studied. Six objects (three presented as gifts) were shown to each participant. Ten minutes later, a free recall and a recognition test were applied. The recognition test had target-objects mixed with six similar distracter objects. Participants were asked to name any object in the recall test and identify each object in the recognition test as known or unknown. RESULTS: The total of gift objects recalled in AD patients (41.6%) was larger than neutral objects (13.3%) and a significant EM recall effect for gifts was found (Wilcoxon: p < .003). EM was not found for recognition in AD patients due to a ceiling effect. Healthy older adults scored overall higher in recall and recognition but showed no EM enhancement due to a ceiling effect. A logistic regression showed that likelihood of emotional recall memory can be modeled as a function of MMSE score (p < .014) and object status (p < .0001) as gift or non-gift. CONCLUSION: Recall memory was enhanced in AD patients for emotional objects indicating that EM in mild to moderate AD although impaired can be provoked with strong emotional load. The logistic regression model suggests that EM declines with the progression of AD rather than disrupts and may be a useful tool for evaluating magnitude of emotional load.