Effect of the route of nutrition and L-alanyl-L-glutamine supplementation in amino acids' concentration in trauma patients.

PURPOSE: Our purpose was to assess the amino acids' (AAs) profile in trauma patients and to assess the effect of the route of nutrition and the exogenous ALA-GLN dipeptide supplementation on plasma AAs' concentration. METHODS: This is a secondary analysis of a previous randomized controlled trial. On day 1 and day 6 after trauma, plasma concentration of 25 AAs was measured using reverse phase high-performance liquid chromatography. Results were analyzed in relation to the route of nutrition and supplementation of ALA-GLN dipeptide. Differences between plasma AAs' concentrations at day 1 and day 6 were evaluated using the Student's t test or Mann-Whitney-Wilcoxon test. One-way ANOVA and the Kruskal-Wallis test were used to compare groups. A two-sided p value less than 0.05 was considered statistically significant. RESULTS: Ninety-eight patients were analyzed. Mean plasma concentrations at day 1 were close to the lower normal level for most AAs. At day 6 we found an increase in the eight essential AAs' concentrations and in 9 out of 17 measured non-essential AAs. At day 6 we found no differences in plasma concentrations for the sum of all AAs (p = .72), glutamine (p = .31) and arginine (p = .23) distributed by the route of nutrition. Administration of ALA-GLN dipeptide increased the plasma concentration of alanine (p = .004), glutamine (p < .001) and citrulline (p = .006). CONCLUSIONS: We found an early depletion of plasma AAs' concentration which partially recovered at day 6, which was unaffected by the route of nutrition. ALA-GLN dipeptide supplementation produced a small increase in plasma levels of glutamine and citrulline.

[Efficacy of the dipeptide N(2)-L-Alanyl-L-glutamine in traumatic patients admitted to the ICU: a prospective, randomized, double-blind, multicentre study]. / Eficacia del dipéptido N(2)-L-Alanil-L-glutamina en los pacientes traumáticos ingresados en la UCI: estudio prospectivo, multicéntrico, aleatorizado y doble ciego; hipótesis y protocolo.

HYPOTHESIS: the endovenous administration of glutamine, independently of the type of nurtrition received, can reduce the ICU length of stay, the incidence of infections and the mortality in the traumatic patients admitted to the ICU. OBJECTIVES: The main objective is to assess the efficacy of glutamine suplementation, given intravenously, to reduce the incidence of infectious complications, mortality and ICU length of stay in the traumatic patients admitted to the ICU. Other objectives are: 1) to assess the efficacy of glutamine in different groups of patients according to the severity and the plasma levels of glutamine. 2) Record all the adverse events due to the intravenous administration of glutamine. METHODS: prospective, randomized, doble-blind and multicenter study with two parallel groups: placebo and treatment group. The patients who fulfill the inclusion criteria will receive either glutamine or placebo, independently of the type on nutrition. Glutamine will be administered as a pharmaconutrient at 0.5 g/kg/day during 5 days as a continous perfusion.

Stress hyperglycaemia in critically ill patients: potential role of incretin hormones; a preliminary study.

BACKGROUND: Stress hyperglycaemia is common in the intensive care unit (ICU) setting and has been related to a worst outcome. OBJECTIVE: The objective was to characterize the association of glucoregulatory hormones, mainly incretins, with the levels of glycaemia, and its relationship with outcome in ICU patients. METHODS: We prospectively studied 60 patients. Stress hyperglycaemia was diagnosed when glycaemia was < 115 mg/dL. At ICU admission we determined glycaemia, insulin, glucagon, cortisol, glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) plasma levels. Groups were compared using Kruskal-Wallis test. The association between glycaemia levels and glucoregulatory hormones was evaluated using linear regression. RESULTS: Forty-five patients (75%) had hyperglycaemia. We observed no differences in glucoregulatory hormones levels between normo- and hyper- glycaemia groups. Glycaemia levels were not significantly correlated with insulin, glucagon, cortisol or GIP levels, but were correlated with GLP-1 (p = 0.04). GLP-1 was also correlated with cortisol (p = 0.01), but failed to show a significant correlation with insulin, glucagon or GIP levels. Lower levels of plasma GLP-1 were found in patients with stress hyperglycaemia requiring vasoactive support (p = 0.02). CONCLUSIONS: Glycaemia levels were correlated with GLP-1 levels in ICU patients. GLP-1 levels were also associated with cortisol. Patients with stress hyperglycaemia who required vasoactive support had lower incretin levels compared with those patients with stress hyperglycaemia who were hemodynamically stables. (ClinicalTrials.gov Identifier: NCT01087372).

Eficacia del dipéptido N(2)-L-Alanil-L-glutamina en los pacientes traumáticos ingresados en la UCI; estudio prospectivo, multicéntrico, aleatorizado y doble ciego; hipótesis y protocolo / Efficacy of the dipeptide N(2)-L-Alanyl-L-glutamine in traumatic patients admitted to the ICU; a prospective, randomized, double-blind, multicentre study

Hipótesis: La suplementación endovenosa con el dipéptido N(2)-L-alanil-L-glutamina, en pacientes traumáticos ingresado en la UCI puede ejercer un efecto beneficioso en cuanto a reducción de la incidencia de infecciones, de la estancia en UCI y de la mortalidad, independientemente del tipo de nutrición (enteral o parenteral) administrada. Objetivos: El objetivo principal es medir la eficacia de la suplementación con el dipéptido, administrado deforma endovenosa, en reducir la incidencia de las complicaciones infecciosas, la mortalidad y la estancia en UCI de los pacientes traumáticos ingresados en la UCI. Otros objetivos secundarios son: 1) Evaluar la eficacia de L-alanil-L-glutamina en diferentes grupos de gravedad y en relación con los niveles plasmáticos de glutamina. 2) Recoger los posibles efectos adversos del dipéptido administrado de forma endovenosa. Metodología: Ensayo clínico prospectivo, multicéntrico, aleatorizado y doble ciego, con dos grupos paralelos de tratamiento, para evaluar eficacia frente a placebo. Los pacientes traumáticos ingresados en la UCI que cumplan los criterios de inclusión/no exclusión, serán aleatorizados para recibir L-alanil-L-glutamina o placebo, independientemente del tipo de nutrición que reciba el paciente (enteral o parenteral) El dipéptido será administrado como un fármaco nutriente en forma de perfusión continua durante 24 horas y durante 5 días a 0,5 g/kg/día(AU)

Hypothesis: the endovenous administration of glutamine, independently of the type of nurtrition received, can reduce the ICU length of stay, the incidence of infections and the mortality in the traumatic patients admitted to the ICU. Objectives: The main objective is to assess the efficacy of glutamine suplementation, given intravenously, to reduce the incidence of infectious complications, mortality and ICU length of stay in the traumatic patients admitted to the ICU. Other objectives are: 1) to assess the efficacy of glutamine in different groups of patients according to the severity and the plasma levels of glutamine. 2) Record all the adverse events due to the intravenous administration of glutamine. Methods: prospective, randomized, doble-blind and multicenter study with two parallel groups: placebo and treatment group. The patients who fulfill the inclusion criteria will receive either glutamine or placebo, independently of the type on nutrition. Glutamine will be administered as a pharmaco nutrient at 0.5 g/kg/day during 5days as a continous perfusion. (AU)

Stress hyperglycaemia in critically ill patients; Potential role of incretinhormones; a preliminary study / Hiperglucemia de estrés en el paciente crítico; papel potencial de las incretinas; estudio preliminar

Background: Stress hyperglycaemia is common in the intensive care unit (ICU) setting and has been related to a worst outcome. Objective: The objective was to characterize the association of glucoregulatory hormones, mainly incretins, with the levels of glycaemia, and its relationship with outcome in ICU patients. Methods: We prospectively studied 60 patients. Stress hyperglycaemia was diagnosed when glycaemia was > 115 mg/dL. At ICU admission we determined glycaemia, insulin, glucagon, cortisol, glucose-dependent insulino -tropic polypeptide (GIP) and glucagon-like peptide-1(GLP-1) plasma levels. Groups were compared using Kruskal-Wallis test. The association between glycaemia levels and glucoregulatory hormones was evaluated using linear regression. Results: Forty-five patients (75%) had hyperglycaemia.We observed no differences in glucoregulatory hormones levels between normo- and hyper- glycaemia groups. Glycaemia levels were not significantly correlated with insulin, glucagon, cortisol or GIP levels, but were correlated withGLP-1 (p = 0.04). GLP-1 was also correlated with cortisol (p = 0.01), but failed to show a significant correlation withinsulin, glucagon or GIP levels. Lower levels of plasmaGLP-1 were found in patients with stress hyperglycaemia requiring vasoactive support (p = 0.02).Conclusions: Glycaemia levels were correlated withGLP-1 levels in ICU patients. GLP-1 levels were also associated with cortisol. Patients with stress hyperglycaemia who required vasoactive support had lower incretin levels compared with those patients with stress hyperglycaemia who were hemodynamically stables.(ClinicalTrials.gov Identifier: NCT01087372) (AU)

Antecedentes: La hiperglucemia de estrés es habitual en el contexto de la Unidad de cuidados intensivos (UCI) y se ha relacionado con un peor pronóstico. Objetivo: el objetivo fue caracterizar la asociación de hormonas glucorreguladoras, principalmente las incretinas, con las glucemias y su relación con el pronóstico de los pacientes de UCI. Métodos: Estudiamos de forma prospectiva a 60pacientes. La hiperglucemia de estrés se diagnosticaba cuando la glucemia era > 115 mg/dl. En el ingreso en la UCI, determinamos la glucemia y las concentraciones plasmáticas de insulina, glucagón, cortisol, polipéptidoinsulinotropo dependiente de glucosa (GIP) y péptido-1de tipo glucagón (GLP-1). Se compararon los grupos mediante la prueba de Kruskal-Wallis. La asociación entre las glucemias y las hormonas contrarreguladoras se evaluó mediante regresión linear. Resultados: 45 pacientes (75%) tenían hiperglucemia.No observamos diferencias en las concentraciones de hormonas glucorreguladoras entre los grupos de normo ehiperglucemia. Las glucemias no se correlacionaron de forma significativa con las concentraciones de insulina,glucagón, cortisol o GIP, pero sí con el GLP-1 (p = 0,04).El GLP-1 también se correlacionó con el cortisol (p =0,01), pero no consiguió mostrar una correlación significativa con las concentraciones de insulina, glucagón o GIP. Se encontraron menores concentraciones plasmáticas de GLP-1 en los pacientes con hiperglucemia de estrés que requerían soporte vasoactivo (p = 0,02). Conclusiones: las glucemias se correlacionaron con las concentraciones de GLP-1 en los pacientes en UCI . Las concentraciones de GLP-1 también se asociaron con el cortisol. Los pacientes con hiperglucemia de estrés que necesitaron soporte vasoactivo tenían menores concentraciones de incretina en comparación con aquellos con hiperglucemia de estrés con estabilidad hemodinámica(ClinicalTrials.gov Identifier: NCT01087372) (AU)

Correlation between brain interstitial and total serum cortisol levels in traumatic brain injury. A preliminary study.

INTRODUCTION: Brain cortisol availability has never been evaluated in patients with traumatic brain injury (TBI). Cerebral microdialysis is a well-established technique for monitoring brain metabolism in neurocritically ill patients, which may be used to measure interstitial cortisol. The objective of this preliminary study was to measure brain interstitial cortisol and its correlation with total serum cortisol in patients with TBI. METHODS: We prospectively studied 6 patients with severe TBI admitted to the Intensive Care Unit of our tertiary University Hospital in which multimodal neuromonitoring including cerebral microdialysis with a high cut-off of 100 k-Da and 20-mm long membrane was used. Serum and brain interstitial cortisol microdialysis samples were obtained every 8 h and analyzed afterwards. RESULTS: Linear regression analysis of total serum cortisol and brain interstitial cortisol in the whole population showed a moderate correlation (R2=0.538, p<0.001, no.=118). However, intra-individual correlation showed a great variability, with correlation coefficients ranging from a R2=0.091 to R2=0.680. CONCLUSION: Our prospective and preliminary study showed a moderate correlation of brain interstitial cortisol and total serum cortisol values in patients with diffuse TBI. However, intra-individual analysis showed a great variability. These results suggest that total serum cortisol may not reflect brain cortisol availability in half of TBI patients.

[Effect of changes in body weight on rest energy expenditure in critically ill patients]. / Influencia de la modificación del peso corporal sobre el gasto energético de reposo en pacientes críticos.

AIM: Critically ill patients may present rapid and significant variations in body weight in excess of 20%, attributed to acute changes in the volume of extracellular water. These changes should not alter the level of metabolic activity, as the extracellular compartment is metabolically inactive. The purpose of this study has been to verify whether or not the rapid changes in body weight presented by critically ill patients over short periods of time alter the at-rest energy expenditure (GER in its Spanish acronym). PATIENTS: Out of a group of 55 critically ill patients whose GER had been repeatedly measured, 15 were chosen as two of their GER measurements complied with the following clinical conditions: a difference in body weight of more than 5%, a time difference of less than 10 days between both measurements, a variation of less than 20% in the calorie intake, a difference in axillary temperature of less than 1 degree centigrade (degree C) and the same sedation and/or analgesia. All of the patients presented acute kidney failure. Their GER was measured with a system based on the bell spirometer (Calorimet). RESULTS: The variation in body weight was 7.3 +/- 2.12 kg. The difference between the GER with high and low body weight was, in absolute terms, 154 +/- 162 kcal/day (p = 0.003) and, in terms of body weight, -0.6 +/- 1.9 kcal/kg/day (p = 0.21). A statistically significant (r = 0.77 and p > 0.001) linear relationship was observed between the variations in body weight and the GER expressed as a percentage [[symbol: see text] GER (%) = -1.77 + [symbol: see text] peso (%)]. CONCLUSION: The variation in body weight presented by critically ill patients over short periods of time is associated with changes in the GER.

Influencia de la modificación del peso corporal sobre el gasto energético de reposo en pacientes críticos / Influence of body weight changes on the at-rest energy expenditure of critically ill patients

Objetivo: Los pacientes críticos pueden presentar rápidas y significativas variaciones de peso corporal, superiores al 20 por ciento, que se atribuyen a cambios agudos del volumen de agua extracelular. Estos cambios no deberían modificar el nivel de actividad metabólica, al ser el compartimento extracelular metabólicamente inactivo. El objetivo del estudio ha sido comprobar si las rápidas variaciones de peso corporal que presentan los pacientes críticos, en cortos períodos de tiempo, no modifican el gasto energético de reposo (GER). Pacientes: De un grupo de 55 pacientes críticos, a los que se había medido repetidamente el GER, se seleccionaron 15 pacientes en los que dos mediciones del GER cumplían las siguientes condiciones clínicas: una diferencia de peso corporal superior al 5 por ciento, una diferencia de tiempo entre ambas mediciones inferior a 10 días, una variación en el aporte calórico inferior al 20 por ciento, una diferencia en la temperatura axilar inferior a 1 grado centígrado (ºC) y la misma sedación y/o analgesia. Todos los ,,pacientes presentaban insuficiencia renal aguda. El GRE se midió con un sistema basado en el espirómetro de campana (Calorimet). Resultados: La variación de peso corporal fue de 7,3+/-2,12 kg. La diferencia entre el GER con el peso corporal alto y ajo fue en valor absoluto de 154+/-162 kcal/d (p=0,003) y referido al peso corporal de - 0,6 +/- 1,9 kcal/kg/día (p=0,21). Se observó una relación lineal, estadísticamente significativa (r=0,77 y p>0,001), entre las variaciones de peso corporal y de GER expresados en porcentaje [E GER ( por ciento) = -1,77 +E peso ( por ciento)]. Conclusión: La variación del peso corporal que presentan los pacientes críticos, en cortos períodos de tiempo, se asocia con cambios en el GER (AU)

Aim: Critically ill patients may present rapid and significant variations in body weight in excess of 20%, attributed to acute changes in the volume of extracellular water. These changes should not alter the level of metabolic activity, as the extracellular compartment is metabolically inactive. The purpose of this study has been to verify whether or not the rapid changes in body weight presented by critically ill patients over short periods of time alter the at-rest energy expenditure (GER in its Spanish acronym). Patients: Out of a group of 55 critically ill patients whose GER had been repeatedly measured, 15 were chosen as two of their GER measurements complied with the following clinical conditions: a difference in body weight of more than 5%, a time difference of less than 10 days between both measurements, a variation of less than 20% in the calorie intake, a difference in axillary temperature of less than 1 degree centigrade (°C) and the same sedation and/or analgesia. All of the patients presented acute kidney failure. Their GER was measured with a system based on the bell spirometer (Calorimet®). Results: The variation in body weight was 7.3 ± 2.12 kg. The difference between the GER with high and low body weight was, in absolute terms, 154 ± 162 kcal/day (p = 0.003) and, in terms of body weight, - 0.6 ± 1.9 kcal/kg/day (p = 0.21). A statistically significant (r = 0.77 and p > 0.001) linear relationship was observed between the variations in body weight and the GER expressed as a percentage [∈GER (%) = - 1,77 + ∈peso (%)]. Conclusion: The variation in body weight presented by critically ill patients over short periods of time is associated with changes in the GER (AU)

Incidence of gastroesophageal reflux and aspiration in mechanically ventilated patients using small-bore nasogastric tubes.

BACKGROUND: Use of a large-bore nasogastric tube (NGT) and patient position are considered key factors in promoting gastroesophageal reflux (GER) and pulmonary aspiration in critically ill patients. The objective of this study was to determine the incidence of GER and pulmonary aspiration of gastric contents in mechanically ventilated (MV) patients using small-bore NGTs. METHODS: We studied 30 patients on mechanical ventilation for acute respiratory failure who tolerated enteral nutrition through a small-bore NGT. Patients were randomly assigned to a group with (n = 16) or without (n = 14) a small-bore NGT and were maintained in a semirecumbent position during the study. GER and aspiration of gastric contents were assessed by a radioisotopic technique. Scans were done 24 hours after technetium-99m administration (n = 30). In 9 patients a dynamic scintigraphy was performed immediately after colloid administration, and samples of blood and tracheal and oropharyngeal secretions were obtained basally, 30 minutes, and 24 hours after technetium administration and analyzed for radioactivity using a gamma counter. RESULTS: Both groups were similar in age, underlying diagnosis, number of days of mechanical ventilation at the day of study, and mortality. There were no GER reaching the oropharynx and aspiration of gastric contents in both groups. CONCLUSIONS: GER and aspiration of gastric contents were not detected in MV patients using small-bore NGTs and may be a simple measure to prevent ventilator-associated pneumonia.

Jugular venous oxygen monitoring: a helpful technique in the early diagnosis of a traumatic carotid-cavernous sinus fistula.

This report describes the early diagnosis of a right traumatic carotid-cavernous sinus fistula (CCSF) in a patient with head injury manifested as an acute increase in right jugular venous oxygen saturation and with no ophthalmic clinical signs. High values of jugular venous oxygen saturation must be cautiously interpreted with the clinical examination and computed tomographic findings to establish an accurate diagnosis of hyperemia with or without a CCSF.

Effects of N-acetylcysteine on tissue oxygenation in patients with multiple organ failure and evidence of tissue hypoxia.

Covert tissue hypoxia, particularly of the splanchnic region, appears important in the pathogenesis of multiple organ failure (MOF). This investigation evaluates the effects of N-acetylcysteine (NAC) upon several measures of tissue oxygenation in 10 patients with severe MOF and evidence of splanchnic hypoxia (as suggested by a pathologically low value (< 7.32) of the pH of the gastric mucosa (pHi)). Patients were studied following a prospective, randomized, placebo-controlled, cross-over design. Measurements included pulmonary and systemic haemodynamics, cardiac output by thermodilution, arterial and mixed venous blood gas values, blood lactate concentration, whole-body oxygen uptake by analysis of the expired gases, and pHi by tonometry. A complete set of measurements was obtained before and 45 min after the infusion of NAC (150 mg.kg-1 in 250 mL of saline) and, also, before and 45 min after the infusion of an equivalent volume of saline. NAC increased the cardiac index and vasodilated the systemic circulation (p < 0.01). However, O2 delivery to the tissues did not increase because the arterial oxygen content fell after NAC (p < 0.01). Mean O2 extraction or lactate concentration did not change after NAC, and pHi fell slightly (from 7.11 +/- 0.21 to 7.07 +/- 0.21; p < 0.05). The infusion of saline did not modify any variable significantly. The O2 extraction fraction increased exponentially in those patients with reduced O2 transport to the tissues. These results argue against a beneficial effect of N-acetylcysteine upon tissue oxygenation in patients with severe multiple organ failure and evidence of splanchnic hypoxia. Furthermore, they suggest that the mechanisms controlling the extraction of oxygen by the peripheral tissues in these patients were not impaired.

Energy expenditure in patients with multiple organ failure.

We measured the level of resting energy expenditure (BEE) and its evolution in patients with multiple organ failure (MOF). We studied 30 patients requiring mechanical ventilation and sedation. REE was measured by means of a closed circuit method on days 1-5, 7, 10 and 14 after initiating the protocol. REE values between 115% and 145% of the REE calculated from the Harris-Benedict's formula were considered as moderate hypermetabolism and values above 145% as severe hypermetabolism. A predictive formula for determining caloric requirements was developed and validated in another 25 MOF patients. In the study group, 25 patients presented moderate hypermetabolism (83%) and two severe hypermetabolism(7%). Mean REE in the whole group was stable but individual patients may have had a large variability in REE. The anthropometric variables, body temperature and reason for admission predicted the REE with a coefficient of determination of 0.73, according to the model: REE= -3295 + 105.5S - 8A + 11.7 W + 7.7 H + 93.2 T + 123.1 Tr - 145.6 Su where: S = sex (male = 1, female = 0); A: age in years; W: weight in Kg; H: height in cm; T: temperature in degrees C; Tr: trauma (Tr = 1); Su: surgical (Su = 1). The reliability of the model, taken from the validation group, showed that the shrinkage was 0.8%. In conclusion, when MOF patients are sedated they present moderate hypermetabolism. Day-to-day variability of REE in the individual patients and the large variability in estimating REE with our formula preclude its clinical utility and we recommend to measure REE in MOF patients.

[CO2 production and thermogenesis induced by enteral and parenteral nutrition]. / Producción de CO2 y termogénesis inducidas por la nutrición enteral y parenteral.

UNLABELLED: The objectives of this study were to quantify, in critically ill patients, the thermogenesis induced by artificial nutrition (AN), when the caloric supply restores the energetic losses, and to evaluate the effects of the AN suppression on the production of CO2 (VCO2). MATERIAL AND METHODS: 20 patients were studied, 14 with mechanical ventilation and 6 with spontaneous respiration, divided into two groups, depending on whether the AN was enteral (EN) or parenteral (PN). The VCO2 and the consumption of oxygen (VO2) were measured by means of the Douglas bag. The resting energy expenditure during the AN (REET) and 2 hours after discontinuing the AN (REE) were measured. The thermogenesis induced by the nutrition (TIN) was defined as the difference between REET and REE, expressed as a percentage of the caloric supply. RESULTS: After discontinuing the AN, there were no statistically significant differences between EN and PN patients in the VCO2 decreases (p = 0.60) and the VO2 decreases (p = 0.78), and in the TIN percentage referred to the caloric supply (p = 0.82). After discontinuing the caloric supply, which was 1.12 times the REET, the VCO2 decreased 5 +/- 4.9% (Confidence interval (CI) of 95%, from 3% to 7%), the VO2 decreased 2 +/- 6.1% (CI of -0.36% to 5.32%), and the TIN represented 3 +/- 4.5% of the caloric supply (CI of 0.72% to 4.95%). CONCLUSIONS: The results of this study indicate that the thermogenesis induced by artificial nutrition, when restores the energetic losses, is equivalent to 3% of the caloric supply. The discontinuation of the artificial nutrition induced a VCO2 decrease of 5% and thus this measure would probably not be useful for decreasing the ventilatory demand.

[Energy consumption in patients with Crohn's disease. An evolutionary study during hospitalization]. / Consumo de energía en pacientes con enfermedad de Crohn. Estudio evolutivo durante la hospitalización.

In Crohn's disease, weight loss and malnutrition are very frequently occurring problems. One explanation of these findings could be an increased energy expenditure. Eleven patients were studied, of which six were women and five were men, during a hospital stay for an active episode of Crohn's disease. In three patients the small intestine was affected, in five the colon, and in the last three both the ileum and the colon were affected. Van Hees' activity index on admittance was 196 +/- 52 (132-265). The energy expenditure at rest (ECR) on admittance, was 11% higher than that found in the normal population (p: n.s.). The energy expenditure decreased weekly, in a statistically significant way, during hospitalization. No significant relationship was found between the Van Hees activity index and any of the parameters used to evaluate the energy needs. Those patients whose body weight was less than 90% of the ideal body weight, presented pathologically elevated energy needs when the energy expenditure was expressed in kcal/kg (p = 0.003). Fever was the only analyzed parameter which showed a significant correlation with the changes in energy expenditure: measured by the oxygen consumption index (p = 0.003) and by the percentage of REE (p = 0.006).

Gastroesophageal reflux in intubated patients receiving enteral nutrition: effect of supine and semirecumbent positions.

The incidence of gastroesophageal reflux (GER) in critically ill patients as well as the effect of a nasogastric tube (NGT) and body position as risk factors for GER were determined. Seventy patients with orotracheal intubation receiving enteral nutrition through a NGT for more than 48 hours were prospectively studied with two randomly assigned body positions: supine or semirecumbent. Detection of GER was achieved by scintigraphy after labeling gastric contents with 500 microCi of technetium-99m sulfur colloid administered through the NGT. In 50 patients scintigraphy was performed after subjects had remained in the randomized position for 2 hours with the NGT pinched. Twenty additional patients were studied after the NGT had been removed. In 50 patients with NGT, GER was present in 74% (37 of 50) and was higher in the supine position (81%, 21 of 26) than in the semirecumbent position (67%, 16 of 24), but this difference was not statistically significant (p = .26). In 20 patients without NGT, the incidence of GER was 35% (7 of 20) and it was also higher in the supine (50%, 6 of 12) than in the semirecumbent position (12%, 1 of 8, p = .16). There was a statistically significant difference between GER in patients with and without NGT (74% vs 35%, p = .0002). These data show that there is a high incidence of GER in patients with orotracheal intubation and NGT. The presence of a NGT is a risk factor for GER. Semirecumbency does not prevent GER, but there is less incidence than in the supine position.

Ascites increases the resting energy expenditure in liver cirrhosis.

The purpose of this study was to investigate the effect of ascites on the energy metabolism of patients with liver cirrhosis. The resting energy expenditure was determined in 10 patients with liver cirrhosis and ascites of moderate or large volume. The resting energy expenditure measurement was performed using indirect calorimetry and the resting energy expenditure predictive value was calculated with the Harris-Benedict equation, both before and after removal of ascitic fluid by paracentesis. Metabolic stress factors were absent in all cases. After an interval of 11.2 +/- 7.7 days between measurements, a weight loss of 16.6 +/- 10.3 kg was observed with paracentesis. The resting energy expenditure measured by indirect calorimetry showed a statistically significant decrease from 1682 +/- 291 to 1523 +/- 240 kcal/day (P less than 0.005) after removal of ascites. The repeatability of our indirect calorimetry method only allowed for the analysis of the results in 4 of 10 patients in whom ascites removal produced a consistent decrease in resting energy expenditure. There were no statistically significant differences between the measurements obtained by indirect calorimetry and those provided by the Harris-Benedict equation, but the latter had a moderate reliability in predicting the real resting energy expenditure of every patient. Our results suggest that, far from being an inert volume, ascites may be associated, at least in some patients, with an increased resting energy expenditure and therefore accelerate the appearance of protein energy malnutrition with corresponding complications.

Validation of a new closed circuit indirect calorimetry method compared with the open Douglas bag method.

New equipment designed for the routine measurement of oxygen uptake (VO2) using a closed circuit method has been validated by comparing it with a standard Douglas bag method. The equipment (The Caloric Measurement Unit, CMU) has been tested in 10 critically ill patients during mechanical ventilation (MV) and in 10 spontaneously breathing healthy subjects. Determinations of VO2 and of the resting energy expenditure (REE) were measured in duplicate with the standard method and once with the CMU. Six additional patients receiving MV were studied with the CMU to evaluate the reproducibility and the effect of FIO2 = 1 vs FIO2 = 0.43 on VO2 measurements. Considering the whole group of 10 patients and 10 subjects, the mean difference of VO2 between both methods was -2 +/- 21 ml/min (95% confidence interval, -11.8 to 7.8 ml/min, p = 0.6) standard deviation. Both methods had a similar reproducibility and the mean difference of VO2 measured at the two different FIO2 with the CMU was -3.2 +/- 11 ml/min (95% confidence interval, -14.7 to 8.4 ml/min, p = 0.5). No statistically significant difference was found between derived REE values obtained from either method. These data show a good correlation between the two methods suggesting that CMU may be used in place of the standard method with the same accuracy in measurement of VO2 even at FIO2 = 1.