Association of Postoperative Serum Lactate Levels with Acute Kidney Injury in Mexican Patients Undergoing Cardiac Surgery.

Acute kidney injury (AKI) is a highly prevalent and a critical complication of cardiac surgery (CS). Serum lactate (sLac) levels have consistently shown an association with morbimortality after CS. We performed a cross-sectional study including 264 adult patients that had a cardiac surgery between January and December 2020. Logistic regression analysis was performed to determine factors associated with AKI development. We measured the postoperative levels of sLac for all participants immediately after CS (T0) and at 4 h (T4) after the surgical intervention. A linear regression model was used to identify the factors influencing both sLac metrics. We identified four risk predictors of AKI; one was preoperative (atrial fibrillation), one intraoperative (cardiopulmonary bypass time), and two were postoperative (length of hospital stay and postoperative sLac). T0 and T4 sLac levels were higher among CS-AKI patients than in Non-CS-AKI patients. Postoperative sLac levels were significant independent predictors of CSA-AKI, and sLac levels are influenced by length of hospital stay, the number of transfused packed red blood cells, and the use of furosemide in CS-AKI patients. These findings may facilitate the earlier identification of patients susceptible to AKI after CS.

Factors Predicting Early Major Adverse Events in the Intensive Care Unit After Successful Cardiac Surgery for Congenital Heart Disease in Full-Term Neonates.

OBJECTIVE: In this study, we aimed to evaluate the factors affecting major adverse event (MAE) development after full-term neonatal cardiac surgery. METHODS: This study was conducted retrospectively on newborns who underwent congenital heart surgery between June 1, 2020, and June 1, 2022. MAE was defined as the presence of at least one of the following: cardiac arrest, unplanned reoperation, emergency chest opening, admission to the advanced life support system, and death. The role of blood lactate level, vasoactive inotropic score (VIS), and cerebral near-infrared spectroscopy (NIRS) changes in predicting MAE was investigated. RESULTS: A total of 240 patients (50% male) were operated during the study period. The median age of patients was seven days (interquartile range 3-10 days). MAE was detected in 19.5% of the cases. Peak blood lactate levels >7 mmol/liter (area under the curve [AUC] 0.72, 95% confidence interval [CI] [0.62-0.82], P<0.001, sensitivity 76%, specificity 82%, positive predictive value [PPV] 88%) was an independent risk factor for MAE (odds ratio [OR] 2.7 [95% CI 1.3-6]). More than 30% change in NIRS value during the operative period (AUC 0.84, 95% CI [0.80-0.88], P<0.001, sensitivity 65%, specificity 85%, PPV 90%) was a strong predictor of MAE. VIS > 10 was an independent risk factor (AUC 0.75, 95% CI [0.70-0.84], P<0.001, sensitivity 86%, specificity 80%, PPV 84%) and strongly predicted MAE (OR 1.4 [95% CI 0.9-5]). CONCLUSION: Cerebral NIRS changes > 30%, high blood lactate levels, and VIS score within the 48 hours may help to predict the development of MAE in the postoperative period.

Factors Predicting Early Major Adverse Events in the Intensive Care Unit After Successful Cardiac Surgery for Congenital Heart Disease in Full-Term Neonates

ABSTRACT Objective: In this study, we aimed to evaluate the factors affecting major adverse event (MAE) development after full-term neonatal cardiac surgery. Methods: This study was conducted retrospectively on newborns who underwent congenital heart surgery between June 1, 2020, and June 1, 2022. MAE was defined as the presence of at least one of the following: cardiac arrest, unplanned reoperation, emergency chest opening, admission to the advanced life support system, and death. The role of blood lactate level, vasoactive inotropic score (VIS), and cerebral near-infrared spectroscopy (NIRS) changes in predicting MAE was investigated. Results: A total of 240 patients (50% male) were operated during the study period. The median age of patients was seven days (interquartile range 3-10 days). MAE was detected in 19.5% of the cases. Peak blood lactate levels >7 mmol/liter (area under the curve [AUC] 0.72, 95% confidence interval [CI] [0.62-0.82], P<0.001, sensitivity 76%, specificity 82%, positive predictive value [PPV] 88%) was an independent risk factor for MAE (odds ratio [OR] 2.7 [95% CI 1.3-6]). More than 30% change in NIRS value during the operative period (AUC 0.84, 95% CI [0.80-0.88], P<0.001, sensitivity 65%, specificity 85%, PPV 90%) was a strong predictor of MAE. VIS > 10 was an independent risk factor (AUC 0.75, 95% CI [0.70-0.84], P<0.001, sensitivity 86%, specificity 80%, PPV 84%) and strongly predicted MAE (OR 1.4 [95% CI 0.9-5]). Conclusion: Cerebral NIRS changes > 30%, high blood lactate levels, and VIS score within the 48 hours may help to predict the development of MAE in the postoperative period.

Role of TRPV4 Channel in Human White Adipocytes Metabolic Activity.

BACKGROUND: Intracellular calcium (Ca2+) homeostasis plays an essential role in adipocyte metabolism and its alteration is associated with obesity and related disorders. Transient receptor potential vanilloid 4 (TRPV4) channels are an important Ca2+ pathway in adipocytes and their activity is regulated by metabolic mediators such as insulin. In this study, we evaluated the role of TRPV4 channels in metabolic activity and adipokine secretion in human white adipocytes. METHODS: Human white adipocytes were freshly cultured and the effects of the activation and inhibition of TRPV4 channels on lipolysis, glucose uptake, lactate production, and leptin and adiponectin secretion were evaluated. RESULTS: Under basal and isoproterenol-stimulated conditions, TRPV4 activation by GSK1016709A decreased lipolysis whereas HC067047, an antagonist, increased lipolysis. The activation of TRPV4 resulted in increased glucose uptake and lactate production under both basal conditions and insulin-stimulated conditions; in contrast HC067047 decreased both parameters. Leptin production was increased, and adiponectin production was diminished by TRPV4 activation and its inhibition had the opposite effect. CONCLUSION: Our results suggested that TRPV4 channels are metabolic mediators involved in proadipogenic processes and glucose metabolism in adipocyte biology. TRPV4 channels could be a potential pharmacological target to treat metabolic disorders.

Behavior of cortisol, ck and lactate in a session of variable resistance / Comportamento do cortisol, cq e lactato em uma sessão de resistência variável / Comportamiento del cortisol, ck y lactato en una sesión de resistencia variable

ABSTRACT Introduction: Complex Training (CT) has been used to achieve Post-activation Potentiation (PAP) of physical capabilities and, in doing so, improve the sports performance of athletes. However, few studies have considered alterations in serum Cortisol, Metabolic Creatine Kinase (MB-CK), Total Creatine Kinase (Total-CK), and Lactate concentrations ([La]) resulting from this training method. Objective: This study determined the behavior of the following blood serum substances in a CT session: Cortisol, MB-CK, Total CK and [La]. Method: Ten military athlete volunteers aged 28.5 ± 4.8 years; 66.2 ± 2.8 kg, 171.4 ± 3.7 cm, 22.6 ± 1.2 kg/m2; 11.3 ± 2.9% of fat tissue took part in the study. The study had a quasi-experimental, intrasubject design. The variable measurements were: Cortisol, MB-CK, Total-CK, and [La], measured before physical exercise and 24 hours post-stress. The CT session consisted of: four series of five repetitions at 30% of 1RM, plus four repetitions at 60% of 1RM, plus three throws of a 575 g projectile, 15 seconds apart. The statistical analysis was carried out through repeated measure ANOVA for Lactate and a Wilcoxon Matched Pairs t-Test for Cortisol, MB-CK and Total-CK. Results: There was no evidence of alterations in the indicators for fatigue ([La] p = 0.36), and muscular injury (Cortisol p = 0.16; MB-CK p = 0.23; Total-CK p = 0.64) after the training sessions. Conclusion: Variables for muscular injury showed no evidence of alterations 24 hours after the CT sessions, hence confirming that the workload did not generate significant post-stress muscular injury. Level of Evidence I; Therapeutic Study: Investigating Treatment Results.

RESUMO Introdução: Os exercícios de Resistência Variável (RV) têm sido utilizados para aumentar a potencialização pós-ativação (PPA) das habilidades físicas e, com isso, melhorar o desempenho desportivo dos atletas, mas poucos estudos se referem às alterações sanguíneas do Cortisol, Creatina Quinase Metabólica (CQ-MB), Creatina Quinase Total (CQ-Total) e concentrações de Lactato ([La]), que provocam esse método de treinamento. Objetivo: Este estudo avaliou o comportamento sanguíneo do Cortisol, CQ-MB, CQ-Total e [La] em um treinamento de RV. Métodos: Dez atletas militares voluntários com 28,5 ± 4,8 anos; 66,2 ± 2,8 Kg; 171,4 ± 3,7 cm; 22,6 ± 1,2 Kg/m2 e 11,3 ± 2,9% de tecido adiposo fizeram parte do estudo. O projeto foi quase experimental intra-sujeito. As medidas variáveis foram: Cortisol, CQ-MB, CQ-Total e [La], medidos antes e 24 horas após o esforço. O treinamento de intervenção com RV consistia em: quatro séries de cinco repetições de 30% de 1RM, mais quatro repetições de 60% de 1 RM, mais três lançamentos de um projetil de 575g, separados por 15 segundos. A análise estatística foi realizada através de médias repetidas ANOVA para Lactato e um Teste t de Wilcoxon Matched para o Cortisol, CQ-MB e CQ-Total. Resultados: Aplicado o treinamento, não foram evidenciadas alterações nos indicadores de fadiga ([La] p = 0,36) e lesão muscular (Cortisol p = 0,16; MB-CQ p = 0,23; CQ-Total p = 0,64). Conclusão: O treinamento com RV não apresentou alterações nas variáveis de lesão muscular após 24 horas da sua aplicação, isso garante que as cargas de trabalho não gerem lesões musculares significativas pós-esforço. Nível de Evidência I; Estudo terapéutico: Investigação dos resultados do tratamento.

RESUMEN Introducción: La Resistencia Variable (VR) es un método de entrenamiento que ha sido utilizado para conseguir Potenciación Post Activación de las capacidades físicas y, con esto, mejorar el rendimiento deportivo de atletas, no obstante, pocos estudios se refieren a las alteraciones sanguíneas de Cortisol, Metabolic Creatine Kinase (CK-MB), Creatine Kinase Total (CK-Total) y concentraciones de Lactato ([La]) que este método provoca. Objetivo: Este estudio determinó el comportamiento sanguíneo del Cortisol, CK-MB, CK-Total y [La] en una sesión de VR. Método: Diez atletas militares voluntarios con 28,5 ± 4,8 años, 66,2 ± 2,8 Kg, 171,4 ± 3,7 cm, 22,6 ± 1,2 Kg/m2; 11,3 ± 2,9% de tejido graso, fueron parte del estudio. El diseño fue cuasi experimental intrasujeto. Las variables medidas fueron: Cortisol, CK-MB, CK-Total y [La], evaluadas 24 horas antes y 24 horas post esfuerzo. La sesión de intervención con VR consistió en: cuatro series de cinco repeticiones al 30% de 1RM más cuatro repeticiones al 60% de 1 RM más tres lanzamientos de un proyectil de 575 g separadas por 15 segundos. El análisis estadístico fue realizado a través de una ANOVA de medias repetidas para el Lactato y con un Test t de Wilcoxon Matched para el Cortisol, CK-MB y CK-Total. Resultados: Aplicado el tratamiento no se evidenciaron alteraciones en los indicadores de daño muscular (Cortisol p = 0,16; MB-CK p = 0,23; CK-Total p = 0,64) ni fatiga ([La] p = 0,36). Conclusiones: El tratamiento con VR no dejó en evidencia alteraciones en las variables de daño muscular a 24 horas de su aplicación, asegurando que las cargas de trabajo no generan daño muscular significativo post esfuerzo. Nivel de Evidencia I; Estudio terapéutico: Investigación de los resultados de un tratamiento.

O sangue venoso coletado do acesso femoral é adequado para estimar a saturação venosa central de oxigênio e os níveis de lactato arterial em pacientes graves? / Is venous blood drawn from femoral access adequate to estimate the central venous oxygen saturation and arterial lactate levels in critically ill patients?

RESUMO Objetivos: Testar se amostras de sangue venoso coletadas do acesso femoral podem ser utilizadas para estimar a saturação venosa central de oxigênio e os níveis de lactato arterial em pacientes graves. Métodos: Foram utilizadas a análise de Bland-Altman e correlações de Spearman para comparar a saturação venosa femoral de oxigênio e a saturação venosa central de oxigênio, assim como os níveis de lactato arterial e femoral. Foi conduzida uma análise predeterminada de subgrupos nos pacientes com sinais de hipoperfusão. Além disso, foi também investigada a concordância clínica. Resultados: Foram obtidas amostras sanguíneas de 26 pacientes. Em 107 amostras pareadas, observou-se correlação moderada (r = 0,686; p < 0,0001) entre a saturação venosa central de oxigênio e a saturação venosa femoral de oxigênio, com um viés de 8,24 ± 10,44 (limites de concordância de 95%: -12,23 a 28,70). Em 102 amostras pareadas, houve forte correlação entre os níveis arteriais de lactato e os níveis de lactato femoral (r = 0,72, p < 0,001) com um viés de -2,71 ± 9,86 (limites de concordância de 95%: -22,3 a 16,61). A presença de hipoperfusão não modificou de forma significante os resultados. A concordância clínica para saturação venosa foi inadequada, com diferentes decisões terapêuticas em 22,4% das situações; para o lactato, isto ocorreu em apenas 5,2% das situações. Conclusão: A saturação venosa de oxigênio femoral não deve ser utilizada em substituição da saturação venosa central de oxigênio. No entanto, os níveis femorais de lactato podem ser utilizados na prática clínica, mas com cautela.

ABSTRACT Objectives: The purpose of this study was to test if venous blood drawn from femoral access can be used to estimate the central venous oxygen saturation and arterial lactate levels in critically ill patients. Methods: Bland-Altman analysis and Spearman correlations were used to compare the femoral venous oxygen saturation and central venous oxygen saturation as well as arterial lactate levels and femoral lactate. A pre-specified subgroup analysis was conducted in patients with signs of hypoperfusion. In addition, the clinical agreement was also investigated. Results: Blood samples were obtained in 26 patients. In 107 paired samples, there was a moderate correlation (r = 0.686, p < 0.0001) between the central venous oxygen saturation and femoral venous oxygen saturation with a bias of 8.24 ± 10.44 (95% limits of agreement: -12.23 to 28.70). In 102 paired samples, there was a strong correlation between the arterial lactate levels and femoral lactate levels (r = 0.972, p < 0.001) with a bias of -2.71 ± 9.86 (95% limits of agreement: -22.03 to 16.61). The presence of hypoperfusion did not significantly change these results. The clinical agreement for venous saturation was inadequate, with different therapeutic decisions in 22.4% of the situation; for lactate, this was the case only in 5.2% of the situations. Conclusion: Femoral venous oxygen saturation should not be used as a surrogate of central venous oxygen saturation. However, femoral lactate levels can be used in clinical practice, albeit with caution.

Inclusão do equivalente do lactato sanguíneo O2 na regressão de intensidade de exercício VO2 aumenta o gasto energético de corrida e diminui sua precisão / Inclusion of blood lactate O2 equivalent in the VO2 exercise intensity regression increases the energy cost of running and lowers its precision / La inclusión del equivalente del lactato sanguíneo O2 en la regresión de intensidad de ejercicio VO2 aumenta el gasto energético de la carrera y disminuye su precisión

INTRODUÇÃO E OBJETIVOS: Investigar se a inclusão do equivalente energético de lactato sanguíneo (LS) em intensidades submáximas alteraria o gasto energético de corrida (Gc) estimado para corrida supramáxima de alta intensidade assim como sua precisão MÉTODOS: O Gc foi determinado a partir da curva de regressão de velocidade do VO2. Para cada sujeito, uma regressão alternativa foi estabelecida em que energia equivalente a 3 ml de O2 kg-1∙mM-1 de LS foi adicionada ao VO2. Testes t pareados, correlações pareadas e plotagem de Bland-Altman foram utilizados para investigar se os dois métodos representam os mesmos fenômenos. RESULTADOS: Os principais achados foram que o Gc previsto para intensidades supramáximas incluídos entre 110 e 160% ao correspondente ao pico de VO2 dos indivíduos aumentou significativamente quando as medidas de LS foram incluídas nas regressões. A inclusão das medidas de LS também aumentaram a imprecisão do Gc a 110, 120, 130, 150 e 160%. CONCLUSÃO: Nossos resultados indicam que a inclusão do equivalente do lactato de O2 na regressão de intensidade de VO2-exercício aumenta o gasto energético e diminui sua precisão.

INTRODUCTION AND OBJECTIVES: Investigate whether the inclusion of the blood lactate (BL) energy equivalent at submaximal intensities would change the energy cost of running (CR) predicted to supramaximal high-intensity running as well as its precision. METHODS: The CR was determined from the slope of the VO2-speed regression. For each subject an alternative regression was established where an energy equivalent of 3 ml O2 kg-1∙mM-1 BL was added to the VO2. Paired t-tests, pairwise correlations and Bland-Altman plots were used to investigate whether the two methods represent the same phenomena. RESULTS: The main findings were that CR predicted to supramaximal intensities comprised between 110% and 160% of that corresponding to the individuals' peak VO2, increased significantly when the BL measurements were included in the regressions. The inclusion of BL measurements also increased the imprecision of the CR at 110%, 120%, 130%, 150% and 160%. CONCLUSIONS: Our results indicate that inclusion of lactate O2 equivalent in the VO2-exercise intensity regression increases the energy cost of running and lowers its precision.

INTRODUCCIÓN Y OBJETIVOS: Investigar si la inclusión del equivalente energético de lactato sanguíneo (LS), en intensidades submáximas, modificaría el gasto energético de la carrera (Gc), estimado para carrera supramáxima de alta intensidad, así como su precisión. MÉTODOS: El Gc fue determinado a partir de la curva de regresión de velocidad del VO2. Para cada individuo, se estableció una regresión alternativa en la cual energía equivalente a 3 ml de O2 kg-1∙mM-1 de LS fue adicionada al VO2. Pruebas t por pares, correlaciones por pares y plotaje de Bland-Altman fueron utilizados para investigar si los dos métodos representan los mismos fenómenos. RESULTADOS: Los hallazgos principales fueron que el Gc previsto para intensidades supramáximas, incluidos 110% y 160% de lo que corresponde al pico de VO2 de los individuos, aumentó significativamente cuando las medidas de LS fueron incluidas en las regresiones. La inclusión de las medidas de LS también aumentó la imprecisión del Gc a 110%, 120%, 130%, 150% y 160%. CONCLUSIÓN: Nuestros resultados indican que la inclusión del equivalente del lactato de O2, en la regresión de intensidad de VO2-ejercicio, aumenta el gasto energético y disminuye su precisión.

Evolução de variáveis hemodinâmicas e perfusionais durante o choque séptico experimental tratado com ressuscitação volêmica guiada por metas / Hemodynamic and perfusion variables during experimental septic shock treated with goal-directed fluid resuscitation

OBJETIVOS: Apesar da ressuscitação volêmica guiada por saturação venosa central de oxigênio (SvcO2) ser considerada atualmente padrão ouro no tratamento da sepse, poucos estudos caracterizaram o perfil evolutivo de variáveis hemodinâmicas e perfusionais durante esta abordagem terapêutica. Este estudo teve por objetivo descrever evolutivamente estes parâmetros durante o choque séptico experimental sem ressuscitação e após 12 horas de ressuscitação guiada por metas. MÉTODOS: Treze porcos (35-45 kg) anestesiados foram submetidos a peritonite por inoculação fecal (0,75g/kg). Após desenvolverem hipotensão persistente, ambos os grupos receberam antibióticos e foram randomizados em dois grupos: controle (n=7), com suporte hemodinâmico otimizado para pressão venosa central entre 8-12mmHg, diurese acima de 0,5ml/kg/h e pressão arterial média maior que 65mmHg; e SvO2 (n=6), com os objetivos acima e SvO2 acima de 65 por cento. As intervenções incluíram ringer lactato e noradrenalina nos 2 grupos e dobutamina no grupo SvO2. Os animais foram tratados durante doze horas ou óbito. RESULTADOS: A sepse não tratada associou-se a uma significante redução da SvO2, PvO2, débito cardíaco e pressão venosa central e aumento da diferença arterio-venosa da saturação de oxigênio e veno-arterial de CO2. Após ressuscitação, esses parâmetros foram corrigidos em ambos os grupos. A ressuscitação guiada por metas associou-se a um melhor perfil hemodinâmico caracterizado por maiores SvO2, débito cardíaco e pressão venosa central. CONCLUSÕES: A sepse não ressuscitada apresenta um perfil hemodinâmico sugestivo de hipovolemia, com piora perfusional e hemodinâmica revertida após ressuscitação volêmica. A ressuscitação guiada por metas associa-se a uma significante melhora dos parâmetros hemodinâmicos e perfusionais.

OBJECTIVES: Although fluid resuscitation guided by central venous oxygen saturation (SvcO2) is currently considered the gold standard in sepsis therapy, few studies have described hemodynamic and perfusion parameters during this procedure. This study aims to describe these parameters during septic shock without resuscitation and after 12 hours of goal-directed resuscitation. METHODS: Thirteen anesthetized pigs (35-45 kg) had peritonitis caused by fecal inoculation (0.75 g/kg). After developing persistent hypotension, both groups were given antibiotics and randomized either to the control group (n=7) or the experimental group (n=6). In the control group, hemodynamic control was optimized to maintain a central venous pressure of 8-12 mmHg, a urinary output above 0.5 mL/kg/hour and a mean arterial blood pressure above 65 mmHg. The experimental group received the above target therapy in addition to maintaining a SvO2 above 65 percent. The interventions included lactated Ringer's solution and norepinephrine for both groups and dobutamine in the SvO2 group. The animals were treated for 12 hours or until death. RESULTS: Untreated sepsis was associated with significant reductions in SvO2, PvO2, cardiac output and central venous pressure in addition to increased arteriovenous oxygen saturation and veno-arterial CO2 differences. Following resuscitation, these parameters were corrected in both groups. Goal-directed resuscitation was associated with a better hemodynamic profile, characterized by higher SvO2, cardiac output and central venous pressure. CONCLUSIONS: Non-resuscitated sepsis showed a hemodynamic profile suggesting hypovolemia, with worsened perfusion and hemodynamics, which is reversed upon fluid resuscitation. Goal-directed resuscitation is associated with significantly improved hemodynamic and perfusion parameters.

A medida do lactato arterial intraoperatório não é determinante de mortalidade em pacientes cirúrgicos de alto risco / Intraoperative lactate measurements are not predictive of death in high risk surgical patients

OBJETIVOS: Classicamente, lactato elevado é considerado como marcador de pior prognóstico, entretanto poucos dados existem a respeito da cinética do lactato no periodo intraoperatório e sua associação com o prognóstico. O objetivo deste estudo foi avaliar em qual momento do período perioperatório o valor do lactato apresenta maior importância prognóstica. MÉTODOS: Estudo prospectivo observacional de um hospital terciário. Foram incluídos pacientes com solicitação de pós-operatório em unidade de terapia intensiva com idade >18 anos, submetidos a cirurgias de grande porte. Pacientes de cirurgias paliativas, com insuficiência cardíaca e/ou hepática grave foram excluídos. Valores de lactato arterial foram mensurados imediatamente antes do início da cirurgia (T0), após indução anestésica (T1), após 3hs de cirurgia (T2), na admissão da unidade de terapia intensiva (T3) e após 6 h da admissão na unidade de terapia intensiva (T4). RESULTADOS: Foram incluídos 67 pacientes. Os valores médios do lactato dos pacientes no T0, T1, T2, T3 e T4 foram respectivamente 1,5 ± 0,8mmol/L, 1,5 ± 0,7mmol/L, 1,8 ± 1,2mmol/L, 2,7 ± 1,7mmol/L e 3,1 ± 2,0mmol/L. A taxa de mortalidade hospitalar foi 25,8 por cento e as dosagens de lactato dos pacientes sobreviventes e dos não sobreviventes 6 h após admissão na unidade de terapia intensiva foram 2,5 ± 1,3 e 4,8 ± 2,8 mmol/L (p<0,0001), respectivamente. As medidas nos demais períodos não demonstraram diferenças estatisticamente significativas dentre estes grupos. CONCLUSÕES: Em pacientes cirúrgicos o lactato arterial no período intraoperatório não apresentou valor prognóstico, entretanto quando avaliado no pós-operatório, ele foi melhor para determinar mortalidade hospitalar.

OBJECTIVES: An increased lactate level is classically considered a marker for poorer prognosis, however little information is available on intraoperative lactate's kinetics and its connection with prognosis. This study aimed to evaluate the time when perioperative lactate is most relevant for prognosis. METHODS: This was an observational prospective study conducted in a tertiary hospital. Patients with requested intensive care unit postoperative stay, aged > 18 years, undergoing major surgery were included. Palliative surgery patients and those with heart and/or severe liver failure were excluded. Arterial lactate levels were measured immediately before the surgery start (T0), after anesthesia induction (T1), 3 hours after the surgery start (T2), intensive care unit admission (T3) and 6 hours after the intensive care unit admission (T4). RESULTS: Sixty seven patients were included. The mean lactate values for the patients' T0, T1, T2 and T4 were 1.5 ± 0.8 mmol/L, 1.5 ± 0.7 mmol/L, 1.8 ± 1.2 mmol/L, 2.7 ± 1.7 mmol/L and 3.1 ± 2.0 mmol/L, respectively. The hospital mortality rate was 25.8 percent, and surviving and non-surviving patients lactate values in the intensive care unit were 2.5 ± 1. and 4.8 ± 2.8 mmol/L (P < 0.0001), respectively. The other times measurements showed no statistically significant differences between the groups. CONCLUSIONS: In surgical patients, intraoperative arterial lactate levels failed to show a predictive value; however during the postoperative period, this assessment was shown to be useful for hospital mortality prediction.

C-reactive protein is not a useful indicator for infection in surgical intensive care units / Proteína C-reativa não é um marcador útil de infecção em unidade de terapia intensiva cirúrgica

CONTEXT AND OBJECTIVE: C-reactive protein (CRP) is commonly used as a marker for inflammatory states and for early identification of infection. This study aimed to investigate CRP as a marker for infection in patients with postoperative septic shock. DESIGN AND SETTING: Prospective, single-center study, developed in a surgical intensive care unit at Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo. METHODS: This study evaluated 54 patients in the postoperative period, of whom 29 had septic shock (SS group) and 25 had systemic inflammatory response syndrome (SIRS group). All of the patients were monitored over a seven-day period using the Sequential Organ Failure Assessment (SOFA) score and daily CRP and lactate measurements. RESULTS: The daily CRP measurements did not differ between the groups. There was no correlation between CRP and lactate levels and the SOFA score in the groups. We observed that the plasma CRP concentrations were high in almost all of the patients. The patients presented an inflammatory state postoperatively in response to surgical aggression. This could explain the elevated CRP measurements, regardless of whether the patient was infected or not. CONCLUSIONS: This study did not show any correlation between CRP and infection among patients with SIRS and septic shock during the early postoperative period.

CONTEXTO E OBJETIVO: A proteína C reativa (PCR) é muito usada como marcador de estados inflamatórios e na identificação precoce de infecção. Este estudo teve como proposta investigar a PCR como marcadora de infecção em pacientes em choque séptico no período pós-operatório. TIPO DE ESTUDO E LOCAL: Estudo prospectivo, monocêntrico, desenvolvido numa unidade de terapia intensiva pós-operatória do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. MÉTODOS: Foram avaliados 54 pacientes no pós-operatório, sendo 29 deles com choque séptico (grupo SS) e 25 com síndrome da resposta inflamatória sistêmica (grupo SI). Todos os pacientes foram acompanhados durante sete dias pelo escore SOFA (Sequential Organ Failure Assessment) e com dosagens diárias de PCR e lactato. RESULTADOS: As dosagens de PCR não diferiram entre os grupos. Não foi observada correlação entre dosagem de PCR e lactato ou escore SOFA nos grupos estudados. Observamos que as concentrações plasmáticas de PCR estavam elevadas em quase todos os pacientes avaliados. Os pacientes no pós-operatório apresentam estado inflamatório em resposta à agressão cirúrgica, sendo este fato capaz de explicar as dosagens de PCR elevadas, independentemente de o paciente estar ou não infectado. CONCLUSÕES: Este estudo não evidenciou correlação entre PCR e infecção nos pacientes com síndrome da resposta inflamatória sistêmica e choque séptico no período pós-operatório precoce.

Adequate systemic perfusion maintained by a CentriMag during acute heart failure.

Mechanical circulatory support during severe acute heart failure presents options for myocardial recovery or cardiac replacement. Short-term circulatory support with the newest generation of magnetically levitated centrifugal-flow pumps affords several potential advantages. Herein, we present our experience with such a pump-the CentriMag Levitronix LLC; Waltham, Mass) centrifugal-flow ventricular assist device-in 4 critically ill patients who were in cardiogenic shock. From November 2007 through March 2008, 3 patients were supported after cardiac surgery, and 1 after chronic heart failure worsened. Two patients were bridged to heart transplantation, and 2 died during support. Perfusion during support was evaluated in terms of serum lactic acid levels and oxygenation values. In all of the patients, the CentriMag's pump flow was adequate, and continuous mechanical ventilation support was provided. Lactic acid levels substantially improved with CentriMag support and were maintained at near-normal levels throughout. At the same time, arterial pH, PO2, and carbon dioxide levels remained within acceptable ranges. No thromboembolic events or mechanical failures occurred. Our experience indicates that short-term use of the CentriMag ventricular assist device during acute heart failure can restore and adequately support circulation until recovery or until the application of definitive therapy.

Serum cortisol, lactate and creatinine concentrations in Thoroughbred fillies of different ages and states of training / Cortisol sérico, concentração de lactato e creatinina em cavalos de corrida Puro Sangue Inglês com diferentes idades e estágios de treinamento

Exercise can be defined as "normal stress" stimulating body functions. Some reports suggest lactate as a stimulator of cortisol levels, while creatinine varies according to the amount of muscle tissue. In the present study we investigated the relationship between creatinine, serum lactate concentration and cortisol levels in training horses. Twenty-three Thoroughbred fillies were used, divided into 3 groups according to age and training protocol: G1, 1-2 years of age (N=7) on pasture, G2, 2-3 years (N=9) starting to be mounted, and G3, 3-4 years (N=7) racing at the Jockey Club. Blood samples were collected weekly during a six-month period at about 1:00 p.m. while the animals were resting. Cortisol was quantified with a commercial kit (Coat-a Count®) and serum creatinine and lactate were evaluated with an autoanalyzer with commercial reagents. Data were evaluated using non-parametric statistical tests, with the level of significance set at P< 0.05. Cortisol concentrations were 149ª + 7, 126b + 6, and 101c + 5 nmol/l, lactate concentrations were 2.1ª + 0.1, 2.0ª + 0.1, and 1.75b + 0.1 mmol/l, and creatinine concentrations were 125ª + 2, 132ª + 2 145b + 3 mumol/l in G1, G2 and G3, respectively. Only G2 showed a low but significant positive correlation of cortisol with lactate and a negative correlation of cortisol with creatinine levels. It was possible to conclude that cortisol, lactate and creatinine varied during horse aging and physical conditioning. The decrease of cortisol concentration (G2) suggests that the better physical condition acquired during training led to the increase of creatinine concentration, possibly related to muscle mass. The lower cortisol and lactate concentrations observed in G3 animals may have been due to greater muscle mass inducing an increase in creatinine concentrations or changes in muscle fiber type during training.(AU)

[...] No presente estudo é investigada a relação entre creatinina, lactato e cortisol séricos em cavalos em treinamento. Vinte e três potras Puro Sangue Inglês foram utilizadas, divididas em 3 grupos de acordo com a idade e protocolo de treinamento: G1, 1-2 anos de idade (n=7) mantidas a pasto, G2, 2-3 anos (n=9) começando a ser montadas e G3, 3-4 anos (n=7) competindo no Jockey Club. Amostras de sangue foram colhidas semanalmente durante 6 meses próximo às 13 h, enquanto os animais descansavam. O cortisol foi quantificado através de kits comerciais (Coat-a CountÒ) e a creatinina sérica e o lactato foram avaliados através de um auto-analyzer, usando reagentes comerciais. Os resultados foram avaliados utilizando testes estatísticos não-paramétricos com nível de significância P<0,05. As concentrações de cortisol foram 149a + 7, 126b + 6, e 101c + 5 nmol/l, as concentrações de lactato foram 2,1a + 0,1, 2,0a + 0,1, e 1,75b + 0,1 mmol/l, e as concentrações de creatinina foram 125a + 2, 132a + 2 145b + 3 mmol/l nos grupos G1, G2 e G3, respectivamente. Somente o G2 apresentou uma pequena, mas significante correlação positiva do cortisol com o lactato e correlação negativa do cortisol com a concentração de creatinina. Foi possível concluir que o cortisol, lactato e a creatinina variaram em função da idade e do condicionamento físico. A diminuição do cortisol observada nos animais do G2, reflete o melhor condicionamento físico adquirido durante o treinamento, que pode ser inferido através do aumento da concentração de creatinina, relacionada a quantidade de massa muscular. A diminuição do cortisol observada nos animais do G3 pode também ser conseqüência do aumento da massa muscular em função do condicionamento, que repercutiu no aumento da creatinina, ou mudanças nos tipos de fibras musculares durante o treinamento.(AU)