Lack of correlation between central venous minus arterial PCO2 to arterial minus central venous O2 content ratio and respiratory quotient in patients with septic shock: A prospective observational study.

OBJECTIVE: Central venous-arterial PCO2 to arterial-central venous O2 content ratio (Pcv-aCO2/Ca-cvO2) is commonly used as a surrogate for respiratory quotient (RQ) and tissue oxygenation. Although Pcv-aCO2/Ca-cvO2 might be associated with hyperlactatemia and outcome, neither the interchangeability with RQ nor the correlation with conclusive variables of anaerobic metabolism has never been demonstrated in septic shock. Our goal was to compare Pcv-aCO2/Ca-cvO2 and RQ in patients with septic shock. DESIGN: Prospective, observational study. SETTING: Two adult ICUs. PATIENTS: Forty-seven patients with septic shock on mechanical ventilation with stable respiratory settings and vasopressor dose after initial resuscitation. INTERVENTIONS: None. MAIN VARIABLES OF INTEREST: We measured arterial and central venous gases, Hb, and O2Hb. Pcv-aCO2/Ca-cvO2 and the ratio of central venous-arterial CO2 content to arterial-central venous O2 content (Ccv-aCO2/Ca-cvO2) were calculated. RQ was determined by indirect calorimetry. RESULTS: Pcv-aCO2/Ca-cvO2 and Ccv-aCO2/Ca-cvO2 were not correlated with RQ (R2 = 0.01, P = 0.50 and R2 = 0.01, P = 0.58, respectively), showing large bias and wide 95 % limits of agreement with RQ (1.09, -1.10-3.27 and 0.42, -1.53-2.37). A multiple linear regression model showed Hb, and central venous PCO2 and O2Hb, but not RQ, as Pcv-aCO2/Ca-cvO2 determinants (R2 = 0.36, P = 0.0007). CONCLUSIONS: In patients with septic shock, Pcv-aCO2/Ca-cvO2 did not correlate with RQ and was mainly determined by factors that modify the dissociation of CO2 from Hb. Pcv-aCO2/Ca-cvO2 seems to be a poor surrogate for RQ; therefore, its values should be interpreted with caution.

Disfunciones del metabolismo del surfactante pulmonar: caso clínico pediátrico / Pulmonary surfactant metabolism dysfunction: A pediatric clinical case report

Las enfermedades pulmonares intersticiales son patologías poco frecuentes en pediatría. Dentro de ellas, se incluyen las disfunciones del metabolismo del surfactante pulmonar, molécula anfipática cuya función es disminuir la tensión superficial y evitar el colapso alveolar. Se presenta el caso de un lactante de 6 meses, en seguimiento por bajo peso, que presentó dificultad respiratoria aguda y cianosis; la radiografía de tórax evidenció infiltrado intersticial, neumomediastino y neumotórax bilateral. Al interrogatorio, surgió antecedente materno de internación al año de vida, con requerimiento de oxigenoterapia prolongada y diagnóstico desconocido; presenta signos de hipoxia crónica. El paciente cursó internación con requerimiento de oxigenoterapia. Se realizaron estudios complementarios en búsqueda de etiología, sin resultados positivos. La tomografía de tórax evidenció opacidades en vidrio esmerilado, engrosamiento del intersticio septal y áreas de atrapamiento aéreo; con resultado de biopsia pulmonar y estudio genético se llegó al diagnóstico de disfunción del metabolismo del surfactante pulmonar.

Interstitial lung diseases are rare in pediatrics. They include dysfunctions in the metabolism of pulmonary surfactant, an amphipathic molecule that reduces surface tension and prevents alveolar collapse. Here we describe the case of a 6-month-old infant controlled for low weight, who presented with acute respiratory distress and cyanosis; his chest X-ray showed interstitial infiltrate, pneumomediastinum, and bilateral pneumothorax. During history-taking, it was noted that his mother had a history of hospitalization at 1 year old with unknown diagnosis, requiring prolonged oxygen therapy; she now shows signs of chronic hypoxia. The patient was hospitalized and required oxygen therapy. Ancillary tests were done to look for the etiology of the condition, with no positive results. A chest computed tomography showed groundglass opacities, thickening of the septal interstitium, and areas of air trapping; based on the results of a lung biopsy and a genetic study, pulmonary surfactant metabolism dysfunction was diagnosed.

Evaluation of the first 5 years of a glutaric aciduria type I neonatal screening programme in Asturias.

INTRODUCTION: . Neonatal screening of glutaric aciduria type 1 (GA-1) has brought radical changes in the course and outcomes of this disease. This study analyses the outcomes of the first 5 years (2015-2019) of the AGA1 neonatal screening programme in our autonomous community. MATERIAL: . We conducted an observational, descriptive and retrospective study. All neonates born between January 1, 2015 and December 31, 2019 that participated in the neonatal screening programme were included in the study. The glutarylcarnitine (C5DC) concentration in dry blood spot samples was measured by means of tandem mass spectrometry applying a cut-off point of 0.25 µmol/L. RESULTS: . A total of 30 120 newborns underwent screening. We found differences in the C5DC concentration based on gestational age, type of feeding and hours of life at sample collection. These differences were not relevant for screening purposes. There were no differences between neonates with weights smaller and greater than 1500 g. Screening identified 2 affected patients and there were 3 false positives. There were no false negatives. The diagnosis was confirmed by genetic testing. Patients have been in treatment since diagnosis and have not developed encephalopathic crises in the first 4 years of life. CONCLUSIONS: . Screening allowed early diagnosis of two cases of GA-1 in the first 5 years since its introduction in our autonomous community. Although there were differences in C5DC levels based on gestational age, type of feeding and hours of life at blood extraction, they were not relevant for screening.

Gyrate atrophy of the choroid and retina: Update on diagnosis and treatment.

Gyrate atrophy of the choroid and retina (GACR) is a rare autosomal recessive disease characterised by elevated plasma ornithine levels due to deficiency of the enzyme ornithine aminotransferase (OAT). The accumulation of this amino acid in plasma leads to the development of patches of chorioretinal atrophy in the peripheral retina extending into the macular area. Patients usually present with night blindness followed by constriction of the visual field and, finally, decreased central vision and blindness. The disease is diagnosed by the presence of the characteristic clinical picture, the presence of hyperornithinaemia in plasma and the detection of mutations in the OAT enzyme gene. There is currently no effective gene therapy and the most common therapeutic intervention mainly involves dietary modifications with arginine restriction. This article aims to summarise the pathogenesis, clinical and diagnostic findings and treatment options in patients with GACR.

Significado biológico y utilidad clínica del lactato en la sepsis / Biological significance and clinical utility of lactate in sepsis

La sepsis es un problema global de salud y la progresión hacia el shock séptico se asocia con un incremento marcado de la morbimortalidad. En este escenario, el aumento del lactato plasmático demostró ser un indicador de gravedad y un predictor de mortalidad, y suele interpretarse casi exclusivamente como marcador de baja perfusión tisular. Sin embargo, últimamente se produjo un cambio de paradigma en la exégesis del metabolismo y propiedades biológicas del lactato. En efecto, la adaptación metabólica al estrés, aun con adecuado aporte de oxígeno, puede justificar la elevación del lactato circulante. Asimismo, otras consecuencias fisiopatológicas de la sepsis, como la disfunción mitocondrial, se asocian con el desarrollo de hiperlactatemia sin que necesariamente se acompañen de baja perfusión tisular. Interpretar el origen y la función del lactato puede resultar de suma utilidad clínica en la sepsis, especialmente cuando sus niveles circulantes fundamentan las medidas de reanimación.

Sepsis is a global health problem; progression to septic shock is associated with a marked increase in morbidity and mortality. In this setting, increased plasma lactate levels demonstrated to be an indicator of severity and a predictor of mortality, and are usually interpreted almost exclusively as a marker of low tissue perfusion. However, a recent paradigm shift has occurred in the exegesis of lactate metabolism and its biological properties. Indeed, metabolic adaptation to stress, even with an adequate oxygen supply, may account for high circulating lactate levels. Likewise, other pathophysiological consequences of sepsis, such as mitochondrial dysfunction, are associated with the development of hyperlactatemia, which is not necessarily accompanied by low tissue perfusion. Interpreting the origin and function of lactate may be of great clinical utility in sepsis, especially when circulating lactate levels are the basis for resuscitative measures.

Osteoporosis management in patients with chronic kidney disease (ERCOS Study): A challenge in nephrological care.

Fracture risk assessment in patients with chronic kidney disease (CKD) has been included in the CKD-MBD ("Chronic Kidney Disease-Mineral and Bone Disorders") complex in international and national nephrology guidelines, suggesting for the first time the assessment of bone mineral density (BMD) if the results can influence therapeutic decision-making. However, there is very little information on actual clinical practice in this population. The main objective of the ERCOS (ERC-Osteoporosis) study is to describe the profile of patients with CKD G3-5D with osteoporosis (OP) and/or fragility fractures treated in specialized nephrology, rheumatology and internal medicine clinics in Spain. Fifteen centers participated and 162 patients (mostly women [71.2%] postmenopausal [98.3%]) with a median age of 77 years were included. Mean estimated glomerular filtration rate (eGFR) was 36 mL/min/1.73 m2 and 38% of the included patients were on dialysis. We highlight the high frequency of prevalent fragility fractures [37.7%), mainly vertebral (52.5%) and hip (24.6%)], the disproportionate history of patients with glomerular disease compared to purely nephrological series (corticosteroids) and undertreatment for fracture prevention, especially in nephrology consultations. This study is an immediate call to action with the dissemination of the new, more proactive, clinical guidelines, and underlines the need to standardize a coordinated and multidisciplinary care/therapeutic approach to these patients in an efficient way to avoid current discrepancies and therapeutic nihilism.

Plant-based diets and their effects on the metabolism and survival of chronic renal patients undergoing conservative treatment

Diet therapy in conservative treatment of chronic kidney disease involves protein restriction, but there is not enough evidence to recommend a particular type of protein, whether animal or plant based. However, studies suggest that plant-based diets help reduce the consumption of total and animal protein, reduce the need for nephroprotective drugs, improve complications and bring advantages in terms of disease progression and patient survival. The article considers up-to-date data on the effects of this diet and observed that when low in protein, primarily vegetable and in some cases supplemented with ketoanalogues, it can result in positive clinical outcomes, such as: delay in the decrease in the glomerular filtration rate, lower concentrations of urea, reduction of serum creatinine and phosphorus concentrations, lower metabolic acidosis, higher insulin sensitivity and lower systemic inflammation. As a whole, this dietary pattern may be able to postpone the start of dialysis with less progression of renal insufficiency. Additional research is needed to better characterize this dietary pattern.

La dietoterapia en el tratamiento conservador de la enfermedad renal crónica implica la restricción de proteínas, pero aún no hay pruebas suficientes para recomendar un tipo concreto de proteínas, ya sean animales o vegetales. Sin embargo, los estudios sugieren que las dietas basadas en plantas ayudan a reducir la ingesta de proteínas totales y animales, disminuyen la necesidad de fármacos nefroprotectores, mejoran las complicaciones y presentan ventajas con respecto a la progresión de la enfermedad y la supervivencia de los pacientes. En este artículo se consideran datos actualizados sobre los efectos de esta dieta y se observa que, cuando es hipoproteica, principalmente vegetal y en algunos casos se complementa con cetoanálogos, puede dar lugar a resultados clínicos positivos, como una disminución retardada de la tasa de filtración glomerular, concentraciones más bajas de urea, concentraciones reducidas de creatinina y fósforo séricos, menor acidosis metabólica, mayor sensibilidad a la insulina y menor inflamación sistémica. En conjunto, este patrón dietético tiene el potencial de retrasar el inicio de la diálisis con una menor progresión de la insuficiencia renal. Es necesario seguir investigando para caracterizar mejor este patrón dietético.

Dexmedetomidine mitigates acute kidney injury after coronary artery bypass grafting: a prospective clinical trial.

INTRODUCTION AND OBJECTIVES: To evaluate the impact of dexmedetomidine impact on cardiac surgery-associated acute kidney injury (CSA-AKI), kidney function, and metabolic and oxidative stress in patients undergoing coronary artery bypass grafting with heart-lung machine support. METHODS: A randomized double-masked trial with 238 participants (50-75 years) undergoing coronary artery bypass grafting was conducted from January 2021 to December 2022. The participants were divided into Dex (n=119) and NS (n = 119) groups. Dex was administered at 0.5 mcg/kg over 10minutes, then 0.4 mcg/kg/h until the end of surgery; the NS group received equivalent saline. Blood and urine were sampled at various time points pre- and postsurgery. The primary outcome measure was the incidence of CSA-AKI, defined as the occurrence of AKI within 96hours after surgery. RESULTS: The incidence of CSA-AKI was significantly lower in the Dex group than in the NS group (18.26% vs 32.46%; P=.014). Substantial increases were found in estimated glomerular filtration rate value at T4-T6 (P<.05) and urine volume 24hours after surgery (P<.01). Marked decreases were found in serum creatinine level, blood glucose level at T1-T2 (P<.01), blood urea nitrogen level at T3-T6 (P<.01), free fatty acid level at T2-T3 (P<.01), and lactate level at T3-T4 (P<.01). CONCLUSIONS: Dex reduces CSA-AKI, potentially by regulating metabolic disorders and reducing oxidative stress. Registered with the Chinese Clinical Study Registry (No. ChiCTR2100051804).

Effect of various dietary fructose concentrations on the gallstone formation process in mice.

Introduction: Background: little information is availaible on the effect of fructose on bile lipids. The first stage in the formation of gallstones corresponds to biliary cholesterol crystallization, derived from the vesicular transporters. The aim of this study was to investigate the influence of consuming diets with different fructose concentrations on serum lipids and their implications on gallstones formation. Methods: BALB/c mice divided into a control group as well as groups were treated with different fructose concentrations (10 %, 30 %, 50 % or 70 %) for different periods (1, 2 or 5 months). Blood, liver and bile samples were obtained. In bile samples, cholesterol and phospholipids levels were analyzed, and cholesterol transporters (vesicles and micelles) were separated by gel filtration chromatography. Results: treated animals showed: 1) increases in body weight similar to the control group; 2) a significant increase in plasma triglycerides only at very high fructose concentrations; 3) a significant increase in total serum cholesterol in the treatment for 1 month; 4) no variations in HDL-cholesterol; 5) a significant increase in serum glucose only at very high fructose concentrations in the second month of treatment; 6) no differences in the plasma alanine-aminotransferase activity; 7) a significant increase in liver triglyceride levels only at very high fructose concentrations; 8) no change in biliary lipid concentrations or in micellar and vesicular phospholipids. Conclusion: changes in plasma, liver and bile lipids were only observed at very high fructose concentrations diets. We conclude that fructose apparently does not alter the gallstone formation process in our experimental model.

Introducción: Introducción: se dispone de escasa información sobre el efecto de la fructosa sobre los lípidos biliares. La primera etapa en la formación de cálculos biliares corresponde a la cristalización del colesterol biliar, derivado de los transportadores vesiculares. El objetivo de este estudio fue investigar la influencia del consumo de dietas con diferentes concentraciones de fructosa en los lípidos séricos y sus implicaciones en el proceso de formación de cálculos biliares. Métodos: ratones BALB/c fueron tratados con diferentes concentraciones de fructosa (10 %, 30 %, 50 % o 70 %) durante diferentes períodos (1, 2 o 5 meses). Se obtuvieron muestras de sangre, hígado y bilis. En muestras de bilis se analizaron los niveles de colesterol y fosfolípidos, y los transportadores de colesterol (vesículas y micelas) se separaron mediante cromatografía de filtración en gel. Resultados: los animales tratados mostraron: 1) aumentos en el peso corporal similares al grupo de control; 2) aumento significativo en los triglicéridos plasmáticos sólo a concentraciones muy altas de fructosa; 3) aumento significativo del colesterol sérico total en el tratamiento durante 1 mes; 4) ninguna variación en los niveles de HDL-colesterol; 5) aumento significativo en glucosa sérica solo a concentraciones muy altas de fructosa; 6) ninguna diferencia en la actividad de la alanina-aminotransferasa plasmática; 7) aumento significativo en los niveles de triglicéridos hepáticos sólo a concentraciones muy altas de fructosa; 8) ningún cambio en las concentraciones de lípidos biliares o en los fosfolípidos micelares y vesiculares. Conclusión: se observaron cambios en los lípidos plasmáticos, hígado y bilis sólo en dietas con concentraciones muy altas de fructosa. Concluimos que la fructosa aparentemente no altera el proceso de formación de cálculos biliares en nuestro modelo experimental.

[Intermittent fasting: effects in diverse clinical settings]. / Ayuno intermitente: efectos en diversos escenarios clínicos.

Introduction: Introduction: intermittent fasting plans propose to limit food intake during specific periods as nutritional therapeutic strategies to treat different metabolic conditions in various clinical entities. However, the heterogeneity between each context of intermittent fasting could generate different results in metabolic parameters. Objective: to evaluate the clinical application of intermittent fasting and to discern whether it offers advantages over other traditional strategies. Methods: structured questions were formulated (PICO), and the methodology followed the guidelines established by the PRISMA 2020 statement. The search was conducted in different databases (PubMed, Cochrane Library and Google Scholar). Results: we found 3,962 articles, of which 56 were finally included; 3,906 articles that did not directly or indirectly answer the structured questions were excluded. Conclusions: compared to conventional diets, the various AI schemes do not generate advantages or disadvantages in terms of weight loss and lipid profile, although in the alternate-day variant there are greater insulin reductions than those observed in the continuous energy restriction. The heterogeneity of the interventions, the populations studied, the comparators, the results, and the type of design make it impossible to extrapolate the effects found in all clinical scenarios and generalize the recommendations.

Introducción: Introducción: los esquemas de ayuno intermitente (AI) proponen limitar la ingestión de alimentos durante periodos específicos. Se han propuesto como estrategia dietoterapéutica para tratar distintas condiciones metabólicas en diversos padecimientos, sin embargo, la heterogeneidad entre cada contexto de ayuno intermitente pudiera generar diferentes resultados en parámetros metabólicos. Objetivo: evaluar la aplicación clínica del ayuno intermitente y discernir si ofrece ventajas sobre otras estrategias tradicionales. Métodos: se formularon preguntas estructuradas (PICO) y la metodología se apegó a las guías establecidas por la declaración PRISMA 2020. Se realizó una búsqueda de literatura científica en las plataformas de PubMed, Cochrane Library y Google Scholar. Resultados: se encontraron 3.962 artículos, de los cuales se incluyeron finalmente 56, eliminando 3.906 trabajos que no contestaban directa o indirectamente las preguntas estructuradas. Conclusiones: frente a las dietas convencionales, los diversos esquemas de AI no generan ventajas ni desventajas en cuanto a pérdida de peso o perfil lipídico, aunque en la variante a días alternos se producen mayores reducciones de insulina a las observadas en la restricción energética continua. La heterogeneidad de las intervenciones y poblaciones estudiadas, así como los comparadores, los desenlaces y el tipo de diseño imposibilitan extrapolar los efectos a todos los escenarios clínicos y generalizar las recomendaciones.

Analysis of the effectiveness coefficient in greco-roman fighting athletes at different levels of competition / Análisis del coeficiente de eficacia en atletas de lucha griego-romana en distintos niveles de competición / Análise do coeficiente de efetividade em atletas de luta greco-romana em diferentes níveis de competição

ABSTRACT Introduction: Wrestling is an ancient combat sport, individual and of complex performance, which integrates high technical and tactical complexity, associated with a bioenergetic interaction and a high coordinative pattern. In Brazil, the number of competitors at different levels has increased significantly in the last years, evidencing the need to search for answers that can help coaches in the different situations of the competitive calendar. The prescription of the means and methods of training in Greco-Roman wrestling aims at the development of the technical effectiveness. However, there is no evidence of indicators of technical effectiveness, in Brazilian elite athletes of Greco-Roman wrestling, in national and international competitions. Objectives: The objective of the study was to verify and to compare the technical effectiveness of the wrestlers of Greco-Roman fight of the Brazilian selection, in two competitions: one in the national level and the other international. Methods: Seven athletes of the Brazilian wrestling team participated of the investigation (age: 25±5 years; stature: 175±12 cm; corporal mass: 80± 21kg). Analysis of the effective, not effective and total technique were accomplished. After identifying the normality of the data (SHAPIRO WILKS), the Student's t test was used to compare the variables, according to the moment evaluated, considering the significance level of 5%. Results: The results showed a significant decrease (p = 0.03) in the standing effective technique and in the total effective technique (p = 0.01), comparing the national competition with the international competition. Conclusion: Technical effectiveness of Brazilian wrestlers was found to be below the indices presented in studies with competitors from countries considered to have high world performance. In international competition, it presents a negative impact compared to national events. Level of Evidence IV; Therapeutic Studies - Investigation of Treatment Results.

RESUMEN Introducción: El Wrestling es una modalidad de combate milenaria, individual y de rendimiento complejo, que integra elevada complejidad técnico-táctica, asociada a una interacción bioenergética y un alto patrón coordinativo. En Brasil, el número de competidores en diferentes niveles aumentó significativamente en los últimos años, evidenciando la necesidad en la búsqueda de respuestas que auxilien a los entrenadores en las diferentes situaciones del calendario competitivo. La prescripción de los medios y métodos de entrenamiento en la lucha greco-romana tiene como objetivo el desarrollo de la efectividad técnica. Entre tanto, no hay evidencias de indicadores de efectividad técnica, en atletas de alto rendimiento brasileño en la lucha greco-romana, en competencias nacionales e internacionales. Objetivos: El objetivo de este estudio fue verificar y comparar la efectividad técnica de los atletas de lucha greco-romana de la selección brasileña, en dos competencias: una a nivel nacional y otra internacional. Métodos: Participaron de la investigación siete atletas de la selección brasileña de lucha greco-romana (edad: 25±5 años; estatura: 175±12 cm; masa corporal: 80± 21kg). Fueron realizados análisis de la técnica efectiva, no efectiva y total. Después de identificar la normalidad de los datos (SHAPIRO WILKS), fue utilizado el test de t de Student para la comparación de las variables, según el momento evaluado, considerando el nivel de significación de 5%. Resultados: Los resultados mostraron una disminución significativa (p = 0,03) en la técnica efectiva en pie y en la técnica efectiva total (p = 0,01), comparándose la competencia nacional con la internacional. Conclusión: Se concluyó que la eficacia técnica de los luchadores brasileños está por debajo de los índices presentados en estudios con competidores de países considerados de alto rendimiento mundial. En la competición internacional, presenta un impacto negativo en comparación con los eventos nacionales. Nivel de Evidencia IV; Estudios Terapéuticos - Investigación de Los Resultados Del Tratamiento.

RESUMO Introdução: O Wrestling é uma modalidade de combate milenar, individual e de rendimento complexo, que integra elevada complexidade técnico-táctica, associada a uma interação bioenergética e um alto padrão coordenativo. No Brasil, o número de competidores em diferentes níveis aumentou significativamente nos últimos anos, evidenciando a necessidade da busca de respostas que auxiliem os treinadores nas diferentes situações do calendário competitivo. A prescrição dos meios e métodos de treinamento na luta greco-romana visa o desenvolvimento da efetividade técnica. Entretanto, não há evidências de indicadores de efetividade técnica, em atletas de elite brasileira de luta greco-romana, em competições nacionais e internacionais. Objetivo: o objetivo do estudo foi verificar e comparar a efetividade técnica dos lutadores de luta greco-romana da seleção brasileira, em duas competições: uma no nível nacional e a outra internacional. Métodos: Participaram da investigação sete atletas da seleção brasileira de luta greco-romana (idade: 25±5 anos; estatura: 175±12 cm; massa corporal: 80± 21kg). Foram realizadas análises da técnica efetiva, não efetiva e total. Após identificar a normalidade dos dados (SHAPIRO WILKS), foi utilizado o teste t de Student para a comparação das variáveis, segundo o momento avaliado, considerando nível de significância de 5%. Resultados: Os resultados mostraram uma diminuição significativa (p = 0,03) na técnica efetiva em pé e na técnica efetiva total (p = 0,01), comparando-se a competição nacional com a internacional. Conclusão: Concluiu-se que a efetividade técnica dos lutadores brasileiros está abaixo dos índices apresentados em estudos com competidores de países considerados de alto desempenho mundial. Em competição internacional, apresenta um impacto negativo comparativamente a eventos nacionais. Nível de Evidência IV; Estudos Terapêuticos - Investigação dos Resultados do Tratamento.

Critical speed, thresholds for vo2max and boundaries of the severe exercise intensity domain / Velocidad crítica, vo2máx y límites de el dominio de la intensidad del ejercicio severo / Velocidade crítica, vo2max e limites de o domínio de intensidade de exercício severo

ABSTRACT Introduction: The severe exercise intensity domain can be defined as the range of work rates or speeds over which VO2max can be elicited. Objectives: Our purpose was to determine if critical speed (running analog of critical power) identifies the lower boundary of the severe domain and to identify the upper boundary of the domain. Methods: Twenty-five individuals performed five running tests to exhaustion, each lasting > 2.5 min and < 16 min. The two-parameter speed vs time-to-exhaustion relationship generated values for critical speed and the three-parameter speed vs time-to-reach-VO2max relationship generated values for the threshold speed above which VO2max can be elicited. The relationships were solved to calculate the minimum time needed to elicit VO2max. Results: Critical speed (3.00 ± 0.38 m·s−1) and the threshold speed above which VO2max can be elicited (2.99 ± 0.37 m·s−1) were correlated (r = 0.83, p < 0.01) and did not differ (p = 0.70), confirming critical speed as the lower boundary of the severe domain. The minimum time needed to elicit VO2max (103 ± 7 s) and the associated highest speed at which VO2max can be elicited (4.98 ± 0.52 m·s−1) identified the upper boundary of the severe domain for these participants. Conclusion: The critical power concept, which requires no metabolic measurements, can be used to identify the lowest speed at which VO2max can be elicited. With addition of metabolic measurements, mathematical modeling can also identify the highest speed and shortest exercise duration at which VO2max can be elicited. Evidence Level I; Validating cohort study with good reference standards.

RESUMEN Introducción: El dominio de la intensidad del ejercicio severo se puede definir como el rango de ritmos o velocidades de trabajo sobre las que se puede obtener el VO2max. Objetivos: Nuestro propósito fue determinar si la velocidad crítica (funcionamiento analógico de potencia crítica) identifica el límite inferior del dominio severo e identificar el límite superior del dominio. Métodos: Veinticinco personas realizaron cinco pruebas de carrera hasta el agotamiento, cada una con una duración de > 2,5 min y <16 min. La relación de dos parámetros de velocidad frente a tiempo de agotamiento generó valores para la velocidad crítica y la relación de tres parámetros de velocidad frente a tiempo de alcance de VO2max generó valores para la velocidad umbral por encima del cual se puede obtener el VO2max. Las relaciones se resolvieron para calcular el tiempo mínimo necesario para obtener el VO2max. Resultados: La velocidad crítica (3,00 ± 0,38 m·s−1) y la velocidad umbral por encima de la cual se puede obtener el VO2max (2,99 ± 0,37 m·s−1) se correlacionaron (r = 0,83, p < 0,01) y no difirieron (p = 0,70), lo que confirma la velocidad crítica como el límite inferior del dominio severo. El tiempo mínimo necesario para obtener el VO2max (103 ± 7 s) y la velocidad más alta asociada a la que se puede obtener el VO2max (4,98 ± 0,52 m·s−1) identificaron el límite superior del dominio severo para estos participantes. Conclusión: El concepto de potencia crítica, que no requiere mediciones metabólicas, se puede utilizar para identificar la velocidad más baja a la que se puede obtener el VO2max. Con la adición de mediciones metabólicas, el modelado matemático también puede identificar la velocidad más alta y la duración más corta del ejercicio a la que se puede obtener VO2max. Nivel de Evidencia I; Estudio de cohortes con alto estándar de referencia.

RESUMO Introdução: O domínio de intensidade de exercício severo pode ser definido como a faixa de taxas de trabalho ou velocidades sobre as quais o VO2max pode ser obtido. Objetivos: Nosso propósito foi determinar se a velocidade crítica (execução analógica da potência crítica) identifica o limite inferior do domínio severo e identificar o limite superior do domínio. Métodos: Vinte e cinco indivíduos realizaram cinco testes de corrida até a exaustão, cada um com duração > 2,5 min e < 16 min. A relação velocidade de dois parâmetros contra tempo até a exaustão gerou valores para a velocidade crítica e a relação velocidade de três parâmetros contra tempo para alcançar o VO2max valores gerados para a velocidade limite acima da qual o VO2max pode ser obtido. As relações foram resolvidas para calcular o tempo mínimo necessário para eliciar o VO2max. Resultados: A velocidade crítica (3,00 ± 0,38 m·s−1) e a velocidade limite acima da qual o VO2max pode ser eliciado (2,99 ± 0,37 m·s−1) foram correlacionadas (r = 0,83, p < 0,01) e não diferiram (p = 0,70), confirmando a velocidade crítica como o limite inferior do domínio grave. O tempo mínimo necessário para eliciar o VO2max (103 ± 7 s) e a maior velocidade associada na qual o VO2max pode ser eliciado (4,98 ± 0,52 m·s−1) identificou o limite superior do domínio severo para esses participantes. Conclusão: O conceito de potência crítica, que não requer medidas metabólicas, pode ser usado para identificar a velocidade mais baixa em que o VO2max pode ser eliciado. Com a adição de medidas metabólicas, a modelagem matemática também pode identificar a velocidade mais alta e a duração mais curta do exercício em que o VO2max pode ser obtido. Nível de Evidência I; Estudo de coorte com alto padrão de referência.

High-intensity interval training in people with spinal cord injury: a systematic review / Entrenamiento por intervalos de alta intensidad en personas con lesiones medulares: una revisión sistemática / Treinamento intervalado de alta intensidade em pessoas com lesão da medula espinhal: revisão sistemática

ABSTRACT Objective: Analyze the effects of high-intensity interval training (HIIT) on cardiometabolic parameters, and cardiorespiratory fitness to compile the most used HIIT training types in adults with spinal cord injury (SCI). Methods: This is a systematic review of searches performed in the electronic databases PubMed / Medline, Science Direct, and Google Scholar. Studies included I) needed to apply HIIT training II) adults with SCI to analyze III) cardiometabolic aspects and cardiorespiratory fitness. Two independent reviewers selected the articles for inclusion, extracted their data, and assessed their methodological quality. Results: 654 studies were found. Thus, 12 studies, 11 pre- and post-intervention, and one control group (CG) with 106 participants were analyzed. Pre- and post-HIITT intervention results revealed significant improvement in cardiorespiratory fitness and cardiometabolic aspects (VO2peak, LDH, HDL, insulin resistance). In addition, GC results revealed significant improvement in cardiorespiratory fitness observed in the intervention group (HIIT) compared to the moderate-low intensity (GC) group. Seven studies used the arm ergometer as the primary exercise modality. Two studies described functional electrical stimulation (FES) performed with the arm ergometer plus electrical stimulation in the lower limbs. None reported heart rate dynamics during the study period. Conclusion: High-intensity interval training improves physical fitness and cardiometabolic health in adults with SCI. Evidence level II; Systematic Review of level II studies.

RESUMEN Objetivo: Analizar los efectos del entrenamiento interválico de alta intensidad (HIIT) sobre los parámetros cardiometabólicos, fitness cardiorrespiratorio y recopilar los tipos de HIIT más utilizados en el entrenamiento en adultos con lesión medular (LME). Métodos: Se trata de una revisión sistemática, para lo cual se realizaron búsquedas en bases de datos electrónicas PubMed/Medline, Science Direct y Google Scholar. Se incluyeron estudios que I) necesitaban aplicar entrenamiento HIIT en II) adultos con SCI y analizar III) aspectos cardiometabólicos y aptitud cardiorrespiratoria. Dos revisores independientes seleccionaron los artículos para su inclusión, extrajeron sus datos y evaluaron su calidad metodológica. Resultados: De los 654 estudios encontrados, se analizaron 12 estudios, 11 pre y post intervención y 1 grupo control (GC) con un total de 106 participantes. Los resultados previos y posteriores a la intervención HIIT revelaron una mejora significativa en la aptitud cardiorrespiratoria y los aspectos cardiometabólicos (VO2pico, LDH, HDL, resistencia a la insulina). Los resultados de GC revelaron una mejora significativa en la aptitud cardiorrespiratoria observada del grupo de intervención (HIIT) en comparación con el grupo de intensidad moderada-baja (GC). Siete estudios utilizaron el ergómetro de brazo como la modalidad principal de ejercicio. Dos estudios describieron la estimulación eléctrica funcional (EEF) realizada con el ergómetro de brazo más la estimulación eléctrica en los miembros inferiores. Ninguno informó la dinámica de la frecuencia cardíaca durante el período de estudio. Conclusiones: El entrenamiento intervalos de alta intensidad mejora la condición física y la salud cardiometabólica en adultos con LME. Evidencia de nivel II; Revisión sistemática de estudios de nivel II.

RESUMO Objetivo: Analisar os efeitos do treinamento intervalado de alta intensidade (HIIT) nos parâmetros cardiometabólicos, aptidão cardiorrespiratória e compilar os tipos de HIIT mais utilizados no treinamento em adultos com lesão da medula espinhal (LME). Métodos: Trata-se de revisão sistemática, para a qual foram realizadas pesquisas nas bases de dados eletrônicas PubMed / Medline, Science Direct e Google Scholar. Foram incluídos estudos em que I) o treinamento HIIT era aplicado em II) adultos com LME e analisaram III) os aspectos cardiometabólicos e aptidão cardiorrespiratória. Dois revisores independentes selecionaram os artigos para a inclusão, extraindo seus dados e avaliarando a sua qualidade metodológica. Resultados: 654 estudos foram encontrados. Desses, 12 estudos, 11 pré e pós intervenção e 1 grupo controle (GC) com um total de 106 participantes foram analisados. Resultados pré e pós intervenção de HIIT revelaram significante melhora na aptidão cardiorrespiratória e aspectos cardiometabólicos (VO2pico, LDH, HDL, resistência à insulina). Resultados do GC revelaram uma significativa melhoria na aptidão cardiorrespiratória observada no grupo de intervenção (HIIT) em relação ao grupo de intensidade moderada-baixa (GC). Sete estudos usaram o ergômetro de braço como modalidade de exercício primária. Dois estudos descreveram a estimulação elétrica funcional (EEF) realizada com o ergômetro de braço adicionando estimulação elétrica nos membros inferiores. Nenhum relatou a dinâmica da frequência cardíaca durante o período do estudo. Conclusão: O treinamento intervalado de alta intensidade melhora a aptidão física e a saúde cardiometabólica em adultos com LME. Nível de evidência II; Revisão sistemática de Estudos de Nível II.

Evaluation of newborn screening in the state of Mato Grosso from 2005 to 2019 / Avaliação da triagem neonatal no Estado de Mato Grosso no período de 2005 a 2019

ABSTRACT Objective: To evaluate quality indicators of the Neonatal Screening Referral Service of the state of Mato Grosso (NSRS-MT) from 2005 to 2019. Methods: Cross-sectional, retrospective, exploratory, descriptive, and observational study from 2005 to 2019. The following parameters were analyzed: age of newborns at the first collection, time between sample collection and arrival at the laboratory, time between the arrival and release of results and time between requesting the second sample and arrival at the NSRS. The population coverage of the program and the incidence of each clinical situation screened were also analyzed. Results: NSRS-MT coverage was analyzed and recorded as 76%. The incidence was analyzed for congenital hypothyroidism (CH) 1:1867, phenylketonuria (PKU) 1:33,311, sickle cell disease (SCD) 1:2004, cystic fibrosis (CF) 1:12,663, congenital adrenal hyperplasia (CAH) 1:15,843, and biotinidase deficiency (DB) 1:25,349. The median age (days) at the first consultation was: 44 for HC, 22 for PKU, 60 for DF, 52 for FC, 79 for HAC and 79 for DB. The mean time between exam collection and delivery to the NSRS was 8.4 days; between the arrival and release of results, 9 days; and for the return of recalls, 59 days. Conclusions: Regarding the coverage of the target population and collection at the ideal age, the NSRS-MT presents values below the national average. However, regarding the mean age at the time of the first consultation, the state's performance is better than the national.

RESUMO Objetivo: Avaliar indicadores de qualidade do Serviço de Referência em Triagem Neonatal do Estado de Mato Grosso (SRTN/MT) no período de 2005 a 2019. Métodos: Estudo transversal, retrospectivo, exploratório, descritivo e observacional, que utilizou dados do formulário FormSUS nos anos de 2005 a 2019. Foram analisados os seguintes parâmetros: idade dos recém-nascidos na primeira coleta, tempo entre coleta da amostra e chegada ao laboratório, tempo entre a chegada e a liberação dos resultados e tempo entre a solicitação da segunda amostra até a chegada ao SRTN. Foram analisadas, também, a cobertura populacional do programa e a incidência de cada situação clínica triada. Resultados: Cobertura do SRTN-MT: 76%. Incidências: hipotireoidismo congênito (HC) 1:1.867, fenilcetonúria (PKU) 1:33.311, doença falciforme (DF) 1:2.004, fibrose cística (FC) 1:12.663, hiperplasia adrenal congênita (HAC) 1:15.843 e deficiência de biotinidase (DB) 1:25.349. A mediana da idade (dias) na primeira consulta foi: 44 para HC, 22 para PKU, 60 para DF, 52 para FC, 79 para HAC e 79 para DB. A média entre a coleta do exame e a entrega no SRTN foi de 8,4 dias; entre a chegada e liberação dos resultados, de 9 dias; e para o retorno de reconvocados, de 59 dias. Conclusões: Com relação à cobertura da população alvo e a coleta na idade ideal, o SRTN apresenta valores abaixo da média nacional. Contudo, quanto à idade média no momento da primeira consulta, o desempenho de MT é melhor que a média nacional.

Calidad y cronotipo del sueño y su relación con la obesidad en población adulta. Revisión bibliográfica narrativa

Introducción: Debido a la alta prevalencia de obesidad a nivel mundial y nacional, y de la incidencia de esta enfermedad en el desarrollo de comorbilidades, estudiar los factores que contribuyan a su desarrollo resulta pertinente. La falta de sueño o el sueño interrumpido pueden estar asociados a la epidemia mundial de la obesidad, y resulta un factor modificable a incluir en su terapéutica. Objetivo: Conocer la evidencia reciente acerca de los mecanismos subyacentes que conforman una posible relación entre la cantidad y/o calidad de sueño con el desarrollo de obesidad en personas adultas Metodología: Revisión bibliográfica de artículos científicos en plataformas virtuales de bases de datos. Se aplicaron distintos filtros: edad (18 a 64 años), estudios realizados en humanos, texto completo, idioma inglés y español, y publicaciones no mayores a 5 años. Los estudios de evaluación de la calidad de sueño debían haber aplicado el Índice de Calidad de Sueño de Pittsburgh, y los de evaluación del cronotipo el Horne and Ostberg's Morningness - Eveningness Questionnaire o el Munich Chronotype Questionnaire . Resultados: Individuos con una insuficiente cantidad y/o calidad de sueño fueron asociados con una mayor probabilidad de desarrollar obesidad. Los principales mecanismos subyacentes encontrados fueron: alteraciones hormonales, metabólicas y un aumento de la ingesta de alimentos principalmente en la noche biológica. Conclusiones: Según la bibliografía seleccionada se concluye que existe evidencia que relaciona la cantidad y/o calidad de sueño con el posible desarrollo de obesidad en población adulta.

Introdução: Devido à alta prevalência da obesidade no mundo e no país e à incidência dessa doença no desenvolvimento de comorbidades, é relevante estudar os fatores que contribuem para o seu desenvolvimento. A falta de sono ou o sono interrompido pode estar associado à epidemia global de obesidade e é um fator modificável a ser incluído em sua terapia. Objetivo: Verificar as evidências recentes sobre os mecanismos subjacentes que compõem uma possível relação entre a quantidade e/ou a qualidade do sono e o desenvolvimento da obesidade em adultos . Metodologia: Revisão bibliográfica de artigos científicos em plataformas de bancos de dados virtuais. Foram aplicados diferentes filtros: idade (18 a 64 anos), estudos em humanos, texto completo, idioma inglês e espanhol e publicações com no máximo 5 anos. Os estudos que avaliaram a qualidade do sono deveriam ter aplicado o Índice de Qualidade do Sono de Pittsburgh, e os que avaliaram o cronotipo deveriam ter aplicado o Horne and Ostberg's Morningness - Eveningness Questionnaire ou o Munich Chronotype Questionnaire . Resultados: Os indivíduos com quantidade e/ou qualidade de sono insuficiente foram associados a uma maior probabilidade de desenvolver obesidade. Os principais mecanismos subjacentes encontrados foram: distúrbios hormonais, metabólicos e aumento da ingestão de alimentos, principalmente na noite biológica. Conclusões: Segundo a bibliografia selecionada, há evidências que relacionam a quantidade e/ou a qualidade do sono com o possível desenvolvimento de obesidade na população adulta

Introduction: As a result of the high prevalence of obesity worldwide and nationally, and because of the incidence of this disease in the development of comorbidities, studying the factors that contribute to its development is necessary. The lack or disrupted sleep that is affecting our civilization, has been associated with the worldwide epidemic of obesity, being a modifiable factor to include in its therapy. Objective: To find recent evidence about the underlying mechanisms that build a possible relationship between sleep duration and/or quality with the development of obesity in adults. Methods: The search of articles was carried out by using virtual platforms of bibliographic databases, which were filtered by: age (18 to 64 years), human studies, full text, English and Spanish language and publications no longer than 5 years. Studies that evaluated sleep quality had to apply the Pittsburgh Sleep Quality Index (PSQI) and those that evaluated chronotype had to use the Horne and Ostberg's Morningness - Eveningness Questionnaire or the Munich Chronotype Questionnaire Results: Individuals with insufficient sleep duration and/or quality were more likely to become obese. Underlying mechanisms found were hormonal and metabolic alterations and an increase in food intake, mainly during the biological night Conclusions: According to the selected bibliography, there is scientific evidence linking sleep duration and/or quality with the possible development of obesity in adults

Effects of an antioxidants cocktail on glucose metabolism at rest, during exercise, and during a glucose load in healthy young subjects

Background: Reactive oxygen species (ROS) regulate glucose metabolism (GM) in skeletal muscle by improving the translocation of GLUT4. Antioxidant supplementation could block this physiological effect, altering glucose signaling during exercise. However, there is limited evidence in humans on whether antioxidant intake affects GM. Therefore, we aimed to determine the effect of an antioxidant cocktail (AOC) on GM at rest and during metabolic challenges. Methods: Ten healthy male subjects received AOC supplementation (1000 mg of Vitamin C, 600 IU of Vitamin E, and 600 mg of α-lipoic acid) or placebo (2.000 mg of talc) before two trials conducted 7 days apart. Trial 1: AOC 120 and 90 minutes before an endurance exercise (EEX) bout at 60 % of maximal oxygen uptake (VO2max); Trial 2: AOC 120 and 90 minutes before an oral glucose tolerance test (OGTT; 75 g glucose). Measurements of gas exchange and capillary blood samples were collected every 15 minutes during both trials. Results: AOC supplementation increased resting glucose levels (p<0.05). During Trial 1 (EEX), the AOC increased carbohydrate oxidation (CHOox) (p= 0.03), without effect in glucose blood levels. During Trial 2 (OGTT), the AOC supplementation had no significant effect on GM parameters. Conclusion: Acute supplementation with AOC increased resting glucose levels and CHOox during EEX in healthy subjects, with no effect on GM during the OGTT.

Antecedentes: Las especies reactivas de oxígeno (ROS) regulan el metabolismo de la glucosa (GM) en el músculo esquelético al mejorar la translocación de GLUT4. La suplementación con antioxidantes podría bloquear este efecto fisiológico, alterando la señalización de la glucosa durante el ejercicio. Sin embargo, existe evidencia limitada en humanos sobre si la ingesta de antioxidantes afecta el GM. Por lo tanto, nuestro objetivo fue determinar el efecto de un cóctel de antioxidantes (AOC) en el GM en reposo y durante desafíos metabólicos. Métodos: Sujetos sanos (sexo masculino; n= 10) recibieron suplementos de AOC (1.000 mg de vitamina C, 600 UI de vitamina E y 600 mg de ácido α-lipoico) o placebo (2.000 mg de talco) previo a dos pruebas realizadas con 7 días de diferencia. Prueba 1: AOC 120 y 90 minutos antes de una serie de ejercicio de resistencia (EEX) al 60% del consumo máximo de oxígeno (VO2max); prueba 2: AOC 120 y 90 minutos antes de una prueba de tolerancia oral a la glucosa (OGTT; 75 g de glucosa). Se obtuvieron datos de intercambio de gaseoso y muestras de sangre capilar cada 15 minutos durante ambas pruebas. Resultados: la suplementación con AOC aumentó los niveles de glucosa en reposo (p<0,05). Durante la prueba 1 (EEX), el AOC aumentó la oxidación de carbohidratos (CHOox) (p= 0,03), sin efecto en los niveles de glucosa en sangre. Durante la prueba 2 (OGTT), la suplementación con AOC no tuvo un efecto significativo en los parámetros de GM. Conclusión: Una suplementación aguda con AOC aumentó los niveles de glucosa en reposo y la CHOox durante EEX en sujetos sanos, sin efecto sobre el GM durante la OGTT.

Hipoglicemia hipocetósica por deficiencia de carnitina en un niño

Durante el ayuno, la oxidación de ácidos grasos y la formación de cuerpos cetónicos son necesarios para la producción de energía. La carnitina es esencial para que los ácidos grasos de cadena larga se transfieran a la mitocondria para la oxidación de ácidos grasos. La deficiencia primaria de carnitina es un defecto recesivo que se expresa con un espectro clínico amplio que incluye descompensación metabólica, hipoglicemia hipocetósica o cardiomiopatía en la niñez, fatigabilidad en la adultez o ausencia de síntomas. En nuestro país no hay publicaciones sobre el tema, por lo que en el presente artículo se reporta el caso de un niño que presentó una deficiencia de carnitina expresada como hipoglicemia hipocetósica y se analiza sus hallazgos clínicos, bioquímicos e histopatológicos.

During fasting, the oxidation of fatty acids and the formation of ketone bodies are necessary for energy production. Carnitine is essential for long-chain fatty acids to be transferred to the mitochondria for fatty acid oxidation. Primary carnitine deficiency is a recessive defect that is expressed with a broad clinical spectrum that includes metabolic decompensation, hypoketotic hypoglycemia or cardiomyopathy in childhood, fatiguability in adulthood or absence of symptoms. In our country there are no publications on the subject, so this article reports the case of a child who had carnitine deficiency expressed as hypoketotic hypoglycemia and its clinical, biochemical and histopathological findings are analyzed.

[Correlation of equations for energy expenditure with indirect calorimetry in critically ill patients]. / Correlación de fórmulas para gasto energético con calorimetría indirecta en pacientes críticos.

Background: Nutrition in the Intensive Care Unit (ICU) is a cornerstone; however, energy requirements are a controversial issue that has not yet been resolved. Calorimetry is the gold standard for calculating energy expenditure, but it is expensive and not available in all ICU areas. Formulas have been developed to calculate basal energy expenditure (BAE) and make the process easier. Objective: To validate the predictive formulas of BAE compared to that obtained with ventilatory indirect calorimetry (IC) within the nutritional assessment in ICU patients. Material and methods: Analytical cross-sectional retrolective study. We performed BAE measurement on patients in the ICU of a third level hospital with ventilatory indirect calorimetry and compared the results obtained with those of the Harris Benedict, Muffin-St. Jeor, Institute of Medicine, and Faisy equations. Results: A total of 49 patients were included; a moderate correlation with statistical significance was found between the BAE measurements obtained by indirect calorimetry, with those obtained by four predictive equations that were studied. The Faisy equation obtained the strongest correction with r = 0.461 (p = 0.001). Conclusion: The correlation between the BAE obtained by predictive equations and by IC goes from mild to moderate, due to the heterogeneity of critical patients and their changing nature throughout their disease.

Introducción: la nutrición en la unidad de cuidados intensivos (UCI) es una piedra angular; sin embargo, los requerimientos energéticos son un tema controversial aún no resuelto. La calorimetría es el estándar de oro para calcular el gasto energético, pero es costosa y no está disponible en todas las áreas de las UCI. Se han desarrollado fórmulas para calcular el gasto energético basal (GEB) y hacer el proceso más sencillo. Objetivo: validar las fórmulas predictivas de GEB comparado con el obtenido con calorimetría indirecta (CI) ventilatoria dentro de la valoración nutricia en los pacientes de UCI. Material y métodos: estudio transversal analítico retrolectivo. Realizamos medición de GEB a los pacientes de la UCI de un hospital de tercer nivel con calorimetría indirecta ventilatoria y se compararon los resultados obtenidos con los de las fórmulas de Harris Benedict, Muffin-St. Jeor, Institute of Medicine y Faisy. Resultados: se incluyeron un total de 49 pacientes; se encontró correlación moderada con significación estadística entre las medidas de GEB obtenidas por calorimetría indirecta, con las obtenidas por cuatro fórmulas predictivas que se estudiaron. La fórmula de Faisy obtuvo la corrección más fuerte con una r = 0.461 (p = 0.001). Conclusión: la correlación entre el GEB obtenido por fórmulas predictivas y por CI es de ligera a moderada, debido a la heterogeneidad del paciente crítico y su naturaleza cambiante a lo largo de su enfermedad.

Lack of change in the respiratory quotient during oxygen supply dependence in endotoxemic shock: a subanalysis of an experimental controlled study / Ausência de alteração no quociente respiratório durante a dependência do suprimento de oxigênio no choque endotoxêmico: subanálise de um estudo experimental controlado

ABSTRACT Objective: To evaluate if the reductions in systemic and renal oxygen consumption are associated with the development of evidence of anaerobic metabolism. Methods: This is a subanalysis of a previously published study. In anesthetized and mechanically ventilated sheep, we measured the respiratory quotient by indirect calorimetry and its systemic, renal, and intestinal surrogates (the ratios of the venous-arterial carbon dioxide pressure and content difference to the arterial-venous oxygen content difference. The Endotoxemic Shock Group (n = 12) was measured at baseline, after 60 minutes of endotoxemic shock, and after 60 and 120 minutes of fluid and norepinephrine resuscitation, and the values were compared with those of a Control Group (n = 12) without interventions. Results: Endotoxemic shock decreased systemic and renal oxygen consumption (6.3 [5.6 - 6.6] versus 7.4 [6.3 - 8.5] mL/minute/kg and 3.7 [3.3 - 4.5] versus 5.4 [4.6 - 9.4] mL/minute/100g; p < 0.05 for both). After 120 minutes of resuscitation, systemic oxygen consumption was normalized, but renal oxygen consumption remained decreased (6.3 [5.9 - 8.2] versus 7.1 [6.1 - 8.6] mL/minute/100g; p = not significance and 3.8 [1.9 - 4.8] versus 5.7 [4.5 - 7.1]; p < 0.05). The respiratory quotient and the systemic, renal and intestinal ratios of the venous-arterial carbon dioxide pressure and content difference to the arterial-venous oxygen content difference did not change throughout the experiments. Conclusion: In this experimental model of septic shock, oxygen supply dependence was not associated with increases in the respiratory quotient or its surrogates. Putative explanations for these findings are the absence of anaerobic metabolism or the poor sensitivity of these variables in detecting this condition.

RESUMO Objetivo: Avaliar se as reduções do consumo de oxigênio sistêmico e renal estão associadas ao desenvolvimento de evidências de metabolismo anaeróbico. Métodos: Esta é uma subanálise de estudo já publicado. Em ovinos anestesiados e ventilados mecanicamente, medimos o quociente respiratório por calorimetria indireta e seus substitutos sistêmicos, renais e intestinais (as razões entre a diferença de pressão venoarterial do teor de dióxido de carbono e a diferença arteriovenosa do teor de oxigênio). O Grupo Choque Endotoxêmico (n = 12) foi medido inicialmente, após 60 minutos do choque endotoxêmico e após 60 e 120 minutos da ressuscitação com fluidos e norepinefrina, e os valores foram comparados com os do Grupo Controle (n = 12) sem intervenções. Resultados: O choque endotoxêmico diminuiu o consumo de oxigênio sistêmico e renal (6,3 [5,6 - 6,6] versus 7,4 [6,3 - 8,5] mL/minuto/kg e 3,7 [3,3 - 4,5] versus 5,4 [4,6 - 9,4] mL/minuto/100g; p < 0,05 para ambos). Após 120 minutos de ressuscitação, o consumo sistêmico de oxigênio foi normalizado, mas o consumo renal de oxigênio permaneceu reduzido (6,3 [5,9 - 8,2] versus 7,1 [6,1 - 8,6] mL/minuto/100g; p = NS e 3,8 [1,9 - 4,8] versus 5,7 [4,5 - 7,1]; p < 0,05). O quociente respiratório e as razões sistêmica, renal e intestinal entre a diferença na pressão venoarterial do teor de dióxido de carbono e a diferença arteriovenosa do teor de oxigênio não se alteraram ao longo dos experimentos. Conclusão: Nesse modelo experimental de choque séptico, a dependência do suprimento de oxigênio não foi associada a aumentos no quociente respiratório ou em seus substitutos. As explicações possíveis para esses achados são a ausência de metabolismo anaeróbico ou a baixa sensibilidade dessas variáveis na detecção dessa condição.