Delta de CO2 como estrategia del manejo integral del paciente con choque séptico en la UCI / CO2 delta as a strategy for the comprehensive management of patients with septic shock in the ICU / Delta CO2 como estratégia para o tratamento integral do paciente com choque séptico na UTI

Resumen: Introducción: el choque séptico es un subconjunto de sepsis en el que las anomalías circulatorias, celulares y metabólicas subyacentes son lo suficientemente profundas para aumentar de manera sustancial la mortalidad. Estos pacientes pueden ser identificados en un contexto clínico de choque séptico con hipotensión persistente. La importancia de vigilar valores de delta de pCO2 (presión parcial de dióxido de carbono) de 6 mmHg sirve como herramienta complementaria para evaluar el flujo sanguíneo adecuado hacia la demanda metabólica global. Objetivo: demostrar que el delta de pCO2 es útil en el manejo integral del paciente con choque séptico en la unidad de cuidados intensivos para dirigir el tratamiento de acuerdo con este biomarcador, que se registró al ingreso y a las 24 horas, se relacionaron al pronóstico y a la mortalidad en choque séptico. Material y métodos: estudio descriptivo, ambispectivo, longitudinal y analítico. El universo se compuso de los pacientes que ingresaron a la Unidad de Cuidados Intensivos del Hospital General «La Villa¼ y del Hospital General «Dr. Rubén Leñero¼. Diseño de la maniobra: se tomaron gasometrías arterial y venosa de los pacientes que ingresaron a la UCI, se calculó el delta de pCO2 para ver si los valores de este biomarcador estaban por arriba o debajo de 6 mmHg, ya que un delta de pCO2 se relaciona con mortalidad; sin embargo, el delta de pCO2 se comparó contra el lactato para correlacionar niveles mayores de lactato de 2 mmol/L con la mortalidad. y finalmente observar cuál de los dos biomarcadores es más útil. Se utilizó estadística descriptica para los resultados. Conclusión: de acuerdo a los resultados encontrados en este estudio, se puede decir que el delta de pCO2 y el lactato predijeron el fallecimiento de 15%, lo cual tiene una significancia positiva débil (p = 0.245).

Abstract: Introduction: septic shock is a subset of sepsis in which underlying circulatory, cellular, and metabolic abnormalities are profound enough to substantially increase mortality. These patients can be identified in a clinical setting of septic shock with persistent hypotension. The importance of monitoring delta pCO2 values of 6 mmHg serves as a complementary tool to assess adequate blood flow towards global metabolic demand. Objective: to demonstrate that the pCO2 delta is useful in the comprehensive management of patients with septic shock in the Intensive Care Unit to direct the treatment according to this biomarker (pCO2 delta) that was recorded at admission and at 24 hours, were related to prognosis and mortality in septic shock. Material and methods: descriptive, ambispective, longitudinal and analytical study. The universe was made up of patients admitted to the ICU of the La Villa and Rubén Leñero General Hospitals. Maneuver design: arterial and venous blood gases were taken from the patients admitted to the ICU, the pCO2 delta was calculated to see if the values of this biomarker were above or below 6 mmHg, since a pCO2 delta is related to with mortality; however, delta pCO2 was compared against Lactate to correlate lactate levels greater than two with mortality and finally see which of the two biomarkers is more useful. Descriptive statistics were used for the results. Conclusion: according to the results found in this study, it can be said that delta pCO2 and lactate predicted the death of 15%, which has a weak positive significance (p = 0.245).

Resumo: Introdução: choque séptico é um subconjunto de sepse em que anormalidades circulatórias, celulares e metabólicas subjacentes são profundas o suficiente para aumentar substancialmente a mortalidade, esses pacientes podem ser identificados em um cenário clínico de choque séptico com hipotensão persistente. A importância do monitoramento de valores Delta de pCO2 de 6 mmHg serve como ferramenta complementar para avaliar o fluxo sanguíneo adequado à demanda metabólica global. Objetivo: demonstrar que o Delta pCO2 é útil no manejo integral de pacientes com choque séptico na Unidade de Terapia Intensiva para direcionar o tratamento de acordo com este biomarcador (Delta pCO2) que foi registrado na admissão e em 24 horas, relacionado ao prognóstico e mortalidade no choque séptico. Material e métodos: estudo descritivo, ambispectivo, longitudinal e analítico. O universo foi constituído pelos pacientes internados na UTI dos Hospitais Gerais La Villa e Rubén Leñero. Desenho da estratégia: foram coletadas gasometrias arteriais e venosas dos pacientes internados na UTI, o Delta pCO2 foi calculado para ver se os valores desse biomarcador estavam acima ou abaixo de 6 mmHg, pois um Delta pCO2 está relacionado com mortalidade; entretanto, Delta pCO2 foi comparado com Lactato para correlacionar níveis de lactato maiores que 2 com mortalidade e finalmente observar qual dos dois biomarcadores é mais útil. Foram usadas estatísticas descritivas para os resultados. Conclusão: de acordo com os resultados encontrados neste estudo, pode-se dizer que Delta pCO2 e Lactato predizem óbito em 15%, o que tem uma fraca significância positiva (p = 0.245).

A Study of Biochemical Changes of Rocuronium Bromide and other Muscle Relaxants in Cardiac Surgery

Introduction: CAPD is one of the renal replacement therapieswhich is gaining popularity in the developing world especiallyIndia. This study was aimed to study the clinical profile andcomplication of Complications of Continuous AmbulatoryPeritoneal Dialysis (CAPD).Material and Methods: Patients on CAPD at our center wereevaluated for their clinical profile, complication and outcomeon follow-up.Results: A total of 100 patients were included in the study.There were 66%males and 34% females. Mean age of thepatients was 47.95± 6 years. Hypertension was seen as etiologyin 36%, Diabetes in 27%, chronic glomerulonephritis in 22%,Analgesic nephropathy in 4%, Obstructive nephropathy in 3%and in 4% cases no obvious cause for CKD could be found.Among the complications pain was seen in 11%, pericatheterleak in 5%, bleeding 7%, intestinal perforation in 2%, herniain 5%, total obstruction in 4%, exit site infection in 7%,tunnel infection in 2% and total 111 episodes of peritonitis.Technique survival at 1 year and 2 years was 97%and 94%respectively. Patient survival at one and two years was 90%and 78% respectivelyConclusion: CAPD presents a viable form of renalreplacement therapy. There has been sustained decrease incomplication rates and improvement in technique and patientsurvival with advancement in catheter implantation andcomplication management

Utilidad de los parámetros gasométricos como predictores de mortalidad en pacientes con choque séptico / Usefulness of gasometric parameters as predictors of mortality in septic shock patients / Utilidade dos parâmetros gasométricos como preditores da mortalidade em pacientes com choque séptico

Resumen: Objetivos: Describir los parámetros gasométricos de la presión de dióxido de carbono, el déficit de base y saturación venosa central en los pacientes en choque séptico y observar si el cambio entre el valor inicial (T0) y a las 24 horas (T1) influye en su pronóstico. Material y métodos: Se realizó un estudio observacional y retrospectivo desde marzo de 2014 a julio de 2016 en pacientes mayores de 18 años con diagnóstico de choque séptico. Se midieron SOFA y APACHE II al ingreso, así como las variables derivadas de las gasometrías venosa central y arterial al diagnóstico del choque séptico (T0) y a las 24 horas del manejo inicial (T1). Resultados: Se incluyeron 39 pacientes: sobrevivientes (n = 25) y no sobrevivientes (n = 14). Al ingreso (T0), hubo diferencias entre ambos grupos en la ΔPCO2 y ΔPCO2/Ca-vO2 (7.2 ± 2.4 versus 8.7 ± 2.0 mmHg, p = 0.05) y (1.7 ± 0.5 versus 2.1 ± 0.9 mmHg/mL, p = 0.05), respectivamente. A las 24 horas (T1), el déficit de base (DB) y la presión arterial media (PAM) mostraron diferencia entre los grupos (-4.5 ± 5.0 versus -9.5 ± 7.7 mEq/L, p = 0.02) y (81 ± 10 versus 70 ± 9 mmHg, p = 0.03). El cambio del déficit de base (ΔDB) entre los valores al ingreso (T0) y a las 24 horas (T1) fue significativo (-4.5 ± 4.1 versus 2.1 ± 6.3 mEq/L, p = 0.001); en la razón ΔPCO2/Ca-vO2 (ΔRatio) no hubo diferencia (-0.02 ± 1.2 versus 0.72 ± 1.7 mmHg/mL, p = 0.13) entre los grupos. Conclusión: Además de la ΔPCO2 y la razón ΔPCO2/Ca-vO2, en este estudio, el déficit de base puede ser una herramienta pronóstica en los pacientes con choque séptico.

Abstract: Objectives: To describe the carbon dioxide parameters, base deficit and central venous saturation in septic shock patients and observe if the change between the initial value (T0) and at 24 hours (T1) influences their prognosis. Material and methods: We performed a retrospective and observational study from March 2014 to July 2016. We included patients at least 18 years old with septic shock diagnosis. We assessed SOFA and APACHE II at admission and the derived gasometric parameters at diagnosis of septic shock and at 24 hours of treatment. Results: We included 39 patients. Survivors (n = 25) and non-survivors (n = 14). Upon admission (T0) there were differences between both groups in ΔPCO2 and ΔPCO2/Ca-vO2 (7.2 ± 2.4 versus 8.7 ± 2.0 mmHg, p = 0.05) and (1.7 ± 0.5 versus 2.1 ± 0.9 mmHg/mL, p = 0.05), respectively. At 24 hours (T1) base deficit (BD) and mean arterial pressure (MAP) showed significant differences (-4.5 ± 5.0 versus -9.5 ± 7.7 mEq/L, p = 0.02) and (81 ± 10 versus 70 ± 9 mmHg, p = 0.03). The change in BD (ΔBD) between (T0) and (T1) was significant (-4.5 ± 4.1 versus 2.1 ± 6.3 mEq/L, p = 0.001) and ΔPCO2/Ca-vO2 ratio (ΔRatio) showed no difference (-0.02 ± 1.2 versus 0.72 ± 1.7 mmHg/mL, p = 0.13) among the groups. Conclusions: Beside ΔPCO2 and ΔPCO2/Ca-vO2 ratio, base deficit can be a prognostic instrument in patients with septic shock.

Resumo: Objetivo: Descrever os parâmetros gasométricos da pressão do dióxido de carbono, o deficit de base e a saturação venosa central em pacientes com choque séptico e observar se a variação entre o valor inicial (T0) e às 24 horas (T1) influencia o prognóstico dos pacientes. Material e métodos: Estudo retrospectivo e observacional desde março de 2014 a julho de 2016 em pacientes com idade superior a 18 anos com diagnóstico de choque séptico. Foram medidos SOFA escore e APACHE II na admissão, bem como as variáveis derivadas a partir da gasometria venosa central e arterial ao diagnóstico de choque séptico (T0) e às 24 horas do tratamento inicial (T1). Resultados: Foram incluídos 39 pacientes: sobreviventes (n = 25) e não sobreviventes (n = 14). Na admissão (T0), existem diferenças entre sobreviventes contra os não sobreviventes na ΔPCO2 e ΔPCO2/Ca-vO2 (7.2 ± 2.4 vs 8.7 ± 2.0 mmHg, p = 0.05) e (1.7 ± 0.5 vs 2.1 ± 0.9 mmHg/mL, p = 0.05), respectivamente. Após 24 horas (T1) o défice de base (DB) e a PAM mostraram diferenças entre os grupos (-4.5 ± 5.0 vs -9.5 ± 7.7 mEq / L, p = 0.02) e (81 ± 10 vs 70 ± 9 mmHg, p = 0.03). O delta DB entre os valores de admissão (T0) e às 24 horas (T1) foi significativa (-4.5 ± 4.1 vs 2.1 ± 6.3 mEq/L, p = 0.001) e na razão ΔPCO2/Ca-vO2 (ΔRatio) não houve diferença entre os grupos (-0.02 ± 1.2 vs 0.72 ± 1.7 mmHg/mL, p = 0.13). Conclusão: Ademais da ΔPCO2 e a razão ΔPCO2/Ca-vO2, neste estudo, o deficit de base pode ser uma ferramenta prognóstica em pacientes com choque séptico.

Validation protocol for multiple blood gas analyzers in accordance with laboratory accreditation programs / Protocolo de validação de múltiplos equipamentos para análise de gases sanguíneos em conformidade com os programas de acreditação laboratorial

ABSTRACTIntroduction:The results of blood gas analysis using different instrumentation can vary widely due to the methodological differences, the calibration procedures and the use of different configurations for each type of instrument.Objective:The objective of this study was to evaluate multiple analytical systems for measurement of blood gases, electrolytes and metabolites in accordance with the accreditation program (PALC) of Sociedade Brasileira de Patologia Clínica/Medicina Laboratorial (SBPC/ML).Materials and methods:20 samples were evaluated in three ABL800 Flex (Radiometer Medical ApS, Denmark) blood gas analyzers, and the results were compared with those of the device in use, which was considered the reference. The analysis of variance (Anova) was applied for statistical purposes, as well as the calculation of mean, standard deviation and coefficient of variation.Results:The p values obtained in the statistical analysis were: pH = 0.983, pO2 = 0.991, pCO2 = 0.353, lactate = 0.584, glucose = 0.995, ionized calcium = 0.983, sodium = 0.991, potassium = 0.926, chlorine = 0.029.Conclusion:The evaluation of multiple analytical systems is an essential procedure in the clinical laboratory for quality assurance and accuracy of the results.

RESUMOIntrodução:Os resultados da análise dos gases sanguíneos utilizando diferentes equipamentos podem apresentar grandes variações decorrentes das diferenças metodológicas, dos procedimentos de calibração e da aplicação de configurações distintas para cada tipo de instrumento.Objetivo:O objetivo deste trabalho foi avaliar múltiplos sistemas analíticos para teste de gases sanguíneos, eletrólitos e metabólitos, em conformidade com o Programa de Acreditação de Laboratórios Clínicos (PALC) da Sociedade Brasileira de Patologia Clínica/Medicina Laboratorial (SBPC/ML).Materiais e métodos:Foram avaliadas 20 amostras em três analisadores de gases sanguíneos ABL800 Flex (Radiometer Medical ApS, Dinamarca) em relação ao equipamento em uso, que foi considerado referência. A análise de variância (Anova) foi aplicada para fins de estudo estatístico dos resultados obtidos nos quatro equipamentos, bem como o cálculo da média, do desvio padrão e do coeficiente de variação.Resultados:Os valores de p obtidos na análise estatística foram: pH = 0,983, pO2 = 0,991, pCO2 = 0,353, lactato = 0,584, glicose = 0,995, cálcio ionizado = 0,983, sódio = 0,991, potássio = 0,926 e cloro = 0,029.Conclusão:A avaliação de múltiplos sistemas analíticos é procedimento essencial no laboratório clínico para garantia da qualidade e da exatidão dos resultados.

The significance of monitoring the gradients between transcutaneous PCO2 and arterial PCO2 in patients with septic shock / 中华急诊医学杂志

Objective To investigate the significance of monitoring P(c-a)CO2 (the gradients between transcutaneous PCO2 and arterial PCO2) in patients with septic shock.Method 31 patients with early septic shock were enrolled as the study group and 20 patients with stable hemodynamics as the control group from Fab.2013 to Sept.2014 in our Intensive Care Unit (ICU).The patients with septic shock were treated guided by early goal directed therapy (EGDT) within 6 hours since hospitalization.The differences of baseline P(c-a) CO2 levels and other index as arterial lactate (LAC) concentration between two groups and the variations of these indexes after EGDT in the study group were compared respectively.Results The baseline levels of P(c-a)CO2 and LAC in patients with septic shock were significantly higher than in patients of control group: (21.2 ± 10.1) mmHg vs.(7.5 ±4.6), P =0.000, and (4.0±2.4) mmol/ Lvs.(1.6 ± 0.5), P =0.000.The areas under receiver operator characteristic (ROC) curve (AUC) for baselineP(c-a)CO2 and LAC were 0.918 (95％ CI: 0.843-0.992) and 0.840 (95％ CI: 0.719-0.962) respectively.A threshold of 14.0 mmHg for P(c-a)CO2 and 2.1 mmol/L for LAC discriminated patients with septic shock from without shock with the same sensibility of 83.9％ and the same specificity of 90.0％, respectively.With regard to prognosis (Day 28), AUC for baseline P(c-a)CO2 and LAC were 0.739 (95％ CI: 0.562-0.917) and0.702 (95％ CI: 0.514-0.889) respectively.A threshold of 21.5 mmHg for P(c-a) CO2 and 3.9 mmol/L for LAC discriminated survivors from nonsurvivors with the same sensibility of 71.4％ and the same specificity of 70.6％ respectively.31 patients in the study group completed EGDT within 6 hours after the admission, 16 (51.6％) passed EGDT and 13 (81.3％) survived, 15 (48.4％) failed EGDT and 4 (26.7％) survived, and survival rates were significantly different, F =9.314, P =0.004.After EGDT, P(c-a) CO2 (18.8 ± 9.4) mmHg and LAC (3.3 ± 2.4) mmol/Lreduced significantly compared with the baselines, all P =0.000.AUC then for P(c-a) CO2 and LAC were 0.742 (95％ CI: 0.562-0.921) and 0.769 (95％ CI: 0.593-0.945), respectively.A threshold of 18.3 mmHg for P(c-a)CO2 and 3.1 mmol/L for LAC discriminated survivors from nonsurvivors with the same sensibility of 71.4％ and the specificity of 71.4％ and of 76.5％ respectively.P(c-a) CO2 and LAC of patients passed EGDT reduced significantly compared with those failed EGDT: (14.8 ± 7.5) mmHgvs.(23.6±9.6) mmHg (P=0.012)、 (2.5±1.5) mmol/L vs.(4.3±2.9) mmol/L (P=0.038), and so did with their baseline : (14.8±7.5) mmHgvs.(18.0±8.1) mmHg, (P=0.042)、 (2.5±1.5) mmol/Lvs.(3.2±1.8) mmol/L, P=0.043.In patients failed EGDT, P(c-a)CO2 and LAC changed little after EGDT, from (24.6 ± 9.2) to (23.6 ± 9.6) mmHg (P =0.238) and from (4.8 ± 2.5) mmol/L to (4.3 ± 2.9) mmol/L (P =0.629).When baseline levels were compared between patients passed EGDT with those failed EGDT, P(c-a) CO2 was (18.0 ±8.1) mmHg vs.(24.6 ± 9.2) mmHg (P =0.042), LAC was (3.2 ± 1.8) mmol/L vs.(4.8 ± 2.5) mmol/L (P =0.050).Conclusions P(c-a) CO2 ＞ 14.0 mmHg could play a role in recognizing early septic shock.EGDT was an effective therapy for the disease and P(c-a)CO2 level could reflect the efficacy of EGDT.P(c-a)CO2 ＞ 21.5mmHg before EGDT and P(c-a) CO2 ＞ 19.3 mmHg after EGDT both could predict the prognosis of patients with septic shock.All above correlated well with LAC and represented a new efficient technique to assess tissue microperfusion.

Diurnal sampling reveals significant variation in CO2 emission from a tropical productive lake

It is well accepted in the literature that lakes are generally net heterotrophic and supersaturated with CO2 because they receive allochthonous carbon inputs. However, autotrophy and CO2undersaturation may happen for at least part of the time, especially in productive lakes. Since diurnal scale is particularly important to tropical lakes dynamics, we evaluated diurnal changes in pCO2and CO2 flux across the air-water interface in a tropical productive lake in southeastern Brazil (Lake Carioca) over two consecutive days. Both pCO2 and CO2 flux were significantly different between day (9:00 to 17:00) and night (21:00 to 5:00) confirming the importance of this scale for CO2 dynamics in tropical lakes. Net heterotrophy and CO2 outgassing from the lake were registered only at night, while significant CO2 emission did not happen during the day. Dissolved oxygen concentration and temperature trends over the diurnal cycle indicated the dependence of CO2 dynamics on lake metabolism (respiration and photosynthesis). This study indicates the importance of considering the diurnal scale when examining CO2emissions from tropical lakes.

É amplamente aceito na literatura que lagos são em geral heterotróficos e supersaturados com CO2 já que recebem carbono alóctone. Porém, autotrofia e insaturação de CO2 podem ocorrer em pelo menos parte do tempo, especialmente em lagos produtivos. Como a escala diurna é particularmente importante para a dinâmica de lagos tropicais, variações diurnas na pCO2 e no fluxo de CO2 através da interface ar-água foram avaliadas num lago tropical produtivo do sudeste do Brasil (Lagoa Carioca) durante dois dias consecutivos. Tanto a pCO2 quanto o fluxo de CO2 foram significativamente diferentes entre o dia (9:00 às 17:00) e a noite (21:00 às 5:00), confirmando a influência desta escala na dinâmica do CO2 na Lagoa Carioca. Foram registradas heterotrofia e emissão de CO2 pela lagoa apenas durante a noite, enquanto durante o dia não houve emissão significativa. Variações na concentração de oxigênio dissolvido e na temperatura ao longo do dia indicaram a dependência da dinâmica do CO2 no metabolismo (respiração e fotossíntese) deste lago. Este estudo indica a importância de se considerar a escala diurna na avaliação da emissão de CO2 por lagos tropicais.

Diurnal sampling reveals significant variation in CO2 emission from a tropical productive lake / Amostragem diurna demonstra variação significativa na emissão de CO2 em um lago tropical produtivo

It is well accepted in the literature that lakes are generally net heterotrophic and supersaturated with CO2 because they receive allochthonous carbon inputs. However, autotrophy and CO2 undersaturation may happen for at least part of the time, especially in productive lakes. Since diurnal scale is particularly important to tropical lakes dynamics, we evaluated diurnal changes in pCO2 and CO2 flux across the air-water interface in a tropical productive lake in southeastern Brazil (Lake Carioca) over two consecutive days. Both pCO2 and CO2 flux were significantly different between day (9:00 to 17:00) and night (21:00 to 5:00) confirming the importance of this scale for CO2 dynamics in tropical lakes. Net heterotrophy and CO2 outgassing from the lake were registered only at night, while significant CO2 emission did not happen during the day. Dissolved oxygen concentration and temperature trends over the diurnal cycle indicated the dependence of CO2 dynamics on lake metabolism (respiration and photosynthesis). This study indicates the importance of considering the diurnal scale when examining CO2 emissions from tropical lakes.

É amplamente aceito na literatura que lagos são em geral heterotróficos e supersaturados com CO2 já que recebem carbono alóctone. Porém, autotrofia e insaturação de CO2 podem ocorrer em pelo menos parte do tempo, especialmente em lagos produtivos. Como a escala diurna é particularmente importante para a dinâmica de lagos tropicais, variações diurnas na pCO2 e no fluxo de CO2 através da interface ar-água foram avaliadas num lago tropical produtivo do sudeste do Brasil (Lagoa Carioca) durante dois dias consecutivos. Tanto a pCO2 quanto o fluxo de CO2 foram significativamente diferentes entre o dia (9:00 às 17:00) e a noite (21:00 às 5:00), confirmando a influência desta escala na dinâmica do CO2 na Lagoa Carioca. Foram registradas heterotrofia e emissão de CO2 pela lagoa apenas durante a noite, enquanto durante o dia não houve emissão significativa. Variações na concentração de oxigênio dissolvido e na temperatura ao longo do dia indicaram a dependência da dinâmica do CO2 no metabolismo (respiração e fotossíntese) deste lago. Este estudo indica a importância de se considerar a escala diurna na avaliação da emissão de CO2 por lagos tropicais.

Valores de referencia de gases arteriales y de electrolitos en caninos de la sabana de Bogotá / Reference Values of Arterial Gases and Electrolytes in Canines from the Bogotá Savanna / Valores de referência de gases arteriais e de eletrólitos em caninos da savana de Bogotá

Debido a la ausencia de valores de gasometría arterial que se ajusten a nuestras condiciones ambientales y a la amplia variedad de datos no actualizados en la literatura y utilizados en la práctica diaria, obtenidos con alturas, razas y equipos diferentes a los disponibles en nuestro medio, es necesario generar conocimiento propio ajustado a nuestra realidad. Se realizó una medición sistemática al azar de sangre arterial y venosa en 100 caninos sanos a la altura de la sabana de Bogotá (Chía: 2652 msnm; Cajicá: 2558 msnm; Sopó: 2650 msnm; La Calera: 2718 msnm y Bogotá: 2630 msnm), utilizando el analizador I-STAT® con cartucho EG7+. Se encontraron valores de referencia de gasometría, electrolitos, bases efectivas y pH. Los valores fueron comparados entre cuatro grupos por peso. Para cada parámetro se realizó estadística descriptiva basada en promedio, desviación estándar, error estándar, y se hallaron los límites de confianza (95%) y los intervalos con desviación estándar (una y dos desviaciones). Se evidenció disminución de PCO2, PO2, SO2, bicarbonato, BE. El pH se encontró levemente aumentado, similar a lo reportado por autores a grandes alturas y diferentes (no corroborado estadísticamente) a reportes en literatura, en los que la altura no fue una variable. Aun así son usados frecuentemente como referencia en la práctica de pequeños animales; solo la presentó diferencias estadísticas por grupos de peso. Como conclusión, se evidenció una regulación del pH sanguíneo eficaz a 2600 msnm, con diferentes valores de bicarbonato, PCO2, PO2, BE, que indican la necesidad de obtener y utilizar valores de referencia acordes con condiciones locales.

Due to the lack of arterial gas values that meet our environmental conditions and the wide variety of out-of-date data in literature and used in everyday practice, obtained with different heights, breeds and equipment to the ones available in our context, it becomes necessary to generate our own knowledge adjusted to our reality. A random systematic measurement of arterial and venous blood was made on 100 healthy canines in the Bogotá Savanna (Chia: 2652 m.a.s.l.; Cajica: 2558 m.a.s.l.; Sopo: 2650 m.a.s.l.; La Calera: 2718 m.a.s.l.; and Bogotá: 2630 m.a.s.l.;), using the I-STAT® analyzer with EG7+ cartridge. Reference values were found for gasometry, electrolytes, effective basis and pH. The values were compared between four groups by weight. Descriptive statistics were made for each parameter based on average, standard deviation and standard error, and the trust limits (95%) and the intervals with standard deviation (one and two deviations) were found. A decrease on PCO2, PO2, SO2, bicarbonate and BE was evident. The pH was found to be slightly increased, similar to the one reported by authors at great heights and different (not statistically confirmed) from reports in literature, where height was not a variable. Even so, they are frequently used as reference in the practice of small animals; only PO2 presented statistical differences by groups of weight. As a conclusion, effective regulation of blood pH was evident at 2600 m.a.s.l., with different bicarbonate values, PCO2, PO2, BE, which suggest the need to obtain and use reference values consistent with local conditions.

Devido à ausência de valores de gasometria arterial que se ajuste a nossas condições ambientais e à ampla variedade de dados não atualizados na literatura e utilizados na prática diária, obtidos com alturas, raças e equipes diferentes aos disponíveis em nosso meio, é necessário gerar conhecimento próprio ajustado a nossa realidade. Realizou-se uma medição sistemática ao azar de sangue arterial e venoso em 100 caninos sãos à altura da savana de Bogotá (Chia: 2652 msnm; Cajicá: 2558 msnm; Sopó: 2650 msnm; a Calera: 2718 msnm e Bogotá: 2630 msnm), utilizando o analisador I-STAT® com cartucho EG7+. Encontraram-se valores de referência de gasometria, eletrólitos, bases efetivas e pH. Os valores foram comparados entre quatro grupos por peso. Para cada parâmetro se realizou estatística descritiva baseada na média, no padrão de desvio, erro padrão, e se encontrou os limites de confiança (95%) e os intervalos com desvio padrão (um e dois desvios). Evidenciou-se diminuição de PCO2, PO2, SO2, bicarbonato, BE. O pH se encontrou levemente aumentado, similar ao reportado por autores a grandes alturas e diferentes (não corroborado estatisticamente) a relatórios em literatura, onde que a altura não foi uma variável.. Ainda assim são usados frequentemente como referência na prática de pequenos animais; só a PO2 apresentou diferenças estatísticas por grupos de peso. Como conclusão, se evidenciou uma regulação do pH sanguíneo eficaz a 2600 msnm, com diferentes valores de bicarbonato, PCO2, PO2, BE, que indicam a necessidade de obter e utilizar valores de referência acordes com condições locais.

Impact of upwelling events on the sea water carbonate chemistry and dissolved oxygen concentration in the Gulf of Papagayo (Culebra Bay), Costa Rica: Implications for coral reefs / Impacto de los eventos de surgencia en la química del carbonato del agua de mar y la concentración de oxígeno disuelto en el Golfo de Papagayo (Bahía Culebra), Costa Rica: Implicaciones para los arrecifes de coral

The Gulf of Papagayo, Pacific coast of Costa Rica, is one of the three seasonal upwelling areas of Mesoamerica. In April 2009, a 29-hour experiment was carried out at the pier of the Marina Papagayo, Culebra Bay. We determined sea surface temperature (SST), dissolved oxygen concentration, salinity, pH, and the partial pressure of CO2 (pCO2). The aragonite saturation state (Ωa) as well as the other parameters of the marine carbonate system such as the total dissolved inorganic carbon (DIC) and the total alkalinity (TA) were calculated based on the measured pH and the pCO2. The entrainment of subsurface waters raised the pCO2 up to 645 µatm. SSTs, dissolved oxygen concentrations decreased form 26.4 to 23.7°C and from 228 to 144 µmol l-1. Ωa dropped down to values of 2.1. Although these changes are assumed to reduce the coral growth, the main reef building coral species within the region (Pocillopora spp. and Pavona clavus) reveal growth rates exceeding those measured at other sites in the eastern tropical Pacific. This implies that the negative impact of upwelling on coral growth might be overcompensated by an enhanced energy supply caused by the high density of food and nutrients and more favorable condition for coral growth during the non-upwelling season.

El Golfo de Papagayo, costa Pacífica de Costa Rica, es una de las tres regiones de afloramiento estacional de Mesoamérica. Las características físicas y químicas del agua que aflora no habían sido estudiadas. Durante 29 horas en Abril 2009, se estudiaron la temperatura superficial del mar (TSM), la concentración de oxígeno disuelto, salinidad, pH y la presión parcial de CO2 (pCO2), en la Marina Papagayo, Bahía Culebra. Con base en las mediciones de pH y pCO2 se calculó el estado de saturación de la aragonita (Ω) y otros parámetros del sistema de carbonatos como lo es el carbono orgánico disuelto (COD) y la alcalinidad total (AT). Los resultados indican que el arrastre por convección del agua sub-superficial durante los eventos de afloramiento aumenta la pCO2 y disminuye la TSM, la concentración de oxígeno disuelto y Ω. Aunque se asume que estas condiciones reducen el crecimiento coralino, las principales especies constructoras de arrecife en la región de Papagayo (Pocillopora spp. y Pavona clavus) tienen las mayores tasas de crecimiento en el Pacífico Tropical Oriental. Esto posiblemente implica que el efecto negativo del afloramiento es compensado por el crecimiento durante la época de no afloramiento.

Molecular Approach for Distal Renal Tubular Acidosis Associated AE1 Mutations

The molecular approaches to distal renal tubular acidosis (dRTA) associated AE1 mutations lead us to understand the genetic and pathophysiological aspects of the acidification defects. An unanticipated high value of the urine-blood (U-B) PCO2 after NaHCO3 loading observed in a case of dRTA and southeast Asian ovalocytosis (SAO) might be from a mistarget of the AE1 to the luminal membrane of type A intercalated cells. The mutations of the AE1 gene resulted in SAO and also affected renal acidification function. Notwithstanding, after the NH4Cl loading in 20 individuals with SAO, the acidification in the distal nephron was normal. The presence of both SAO and G701D mutations of AE1 gene would explain the abnormal urinary acidification in the patients with the compound heterozogosity. In terms of the effect of the mutations on trafficking of AE1, truncated kidney isoform (kAE1) of wild-type showed a 'dominant-positive effect' in rescuing the recessive mutant kAE1 (S773P or G701D) trafficking to the plasma membrane, in contrast with the dominant mutant kAE1 (R589H) resulting in a 'dominant-negative effect' when heterodimerized with the wild-type kAE1. It is notable that the dominant mutants kAE1 (R901X or G609R) expression in MDCK cells clearly results in aberrant surface expression with some mutant protein appearing at the apical membrane. These might result in net bicarbonate secretion and increasing U-B PCO2 in the distal nephron. The molecular physiological and genetic approaches have permitted identification of the molecular defects, predominantly in transporter proteins, and should in turn prompt development of novel therapeutic strategies.

A Clinical Study on Gastric Intramucosal PCO_2 and pH During Weaning from mechanical Ventilation / 医学研究杂志

Objective To observe the gastric intramucosal pH( pHi) and gastric intramucosal carbon dioxide tension (PgCO2) in patients, using an automated recirculating air tonometer during weaning from mechanical ventilation ,and to study the value of intramucosal PCO2 and pH measurements to predict weaning outcome from mechanical ventilation.Methods The study population included thirty -two adult critically patients who were mechanically ventilated because of acult respiratory failure and were considered ready to be weaned. Thirty-two patients were randomly assigned to synchronized intermittent mandatory ventilation combined with positive end-expiratory pressure and pressure support ventilation (SIMV+PEEP+PSV) group and continuous positive airway pressure with pressure support ventilation (CPAP+PSV)group,sixteen patients in each group . Respiratory and hemodynamic variables were measured during the weaning process. Simulaneously, the gastric intramucosal PCO2 and pH were measured. At the same time, an arterial blood sample was drawn for blood gas analysis.Results Eighteen patients were successfully weaned from mechanical ventilation and fourteen failed. The gastric intramucosal pH was initially 7.35?0.13 and decreased to 7.238?0.18 during the weaning process in patients who failed (P

Electrolyte and Gas Analysis from Dorsal Vein of Hand during General Inhalational Anesthesia / 대한구급학회지

BACKGROUND: To assess the acid-base status and to measure PO2 and PCO2, arterial blood gases (ABG) has been checked usually. We compared the venous blood gases (VBG) from dorsal vein of hand to ABG from radial artery, and tried to determine whether venous blood gas analysis (VBGA) could be the alternative of ABGA. METHODS: Thirty patients who needed continuous arterial pressure monitoring were chosen. At the completion of stability of HR and BP after induction of general inhalational anesthesia, the ABG from radial artery and VBG from dorsal vein of hand were compared. RESULTS: Laboratory findings were as follows (mean+/-SD): arterial pH, 7.44+/-0.04; venous pH, 7.43+/-0.04; arterial HCO3-, 25.56+/-2.39 mmol/L; venous HCO3-, 25.51+/-2.09 mmol/L. The mean values of arterial and venous PO2 were significantly different (247.8+/-48.9 mmHg versus 187.8+/-41.6 mmHg), but the arterial and venous PO2 values were significantly correlated (r=0.706). The PCO2 (r= 0.883), pH (r=0.912), and HCO3- (r=0.901) values, and base excesses of arterial and venous blood (r=0.926) were highly correlated. Also, arterial and venous serum electrolyte (sodium, potassium, and calcium) were highly correlated. CONCLUSIONS: Venous blood gas analysis from dorsal vein of hand can be effectively used as the alternative method to evaluate the acid-base status, PO2, and PCO2, instead of ABGA during general inhalational anesthesia.

The effect of gastric intraumucosal pH during orthotopic liver transplantation / 西安交通大学学报(医学版)

Objective To investigate the ch an ges of gastric intramucosal pH (pHi) during orthotopic liver transplantation (OL T) without venovenous bypasss. Methods Twenty patients (14 males and 6 females) aged (46.7 ?4.6) years, undergoing orthotopic liver transplantation without venovenous byp asss, were included in this study. A gastric tube technique was used to draw gas tric juice 3～5 mL to determine pHi and PiCO 2 before OLT, at 20 min preanhep atic phase, 30 min anhepatic phase, 30 min new hepatic phase and at 2 h and 2 4 h after operation. The arterial blood samples collected taken for the measure ments of PaCO 2, PO 2, pH, BE and HCO 3- at the same time point s as above. pHi was calculated through Henderson-Hasselbach equation. Results The gastric intraumucosal pH (pHi) was decreased significant ly at the time points of 30 min anhepatic phase and 30 min new hepatic phase c ompared with before operation (P

The Effect of Lung Disease in the Arterial to End-Tidal Carbon Dioxide Tension Difference / 대한마취과학회지

BACKGROUND: The purpose of this study was to evaluate the effects of lung disease on the difference between arterial and end-tidal carbon dioxide tension by placing patients from the supine to the lateral decubitus position and by the changes from two lung ventilation (TLV) to one lung ventilation (OLV) during thoracic surgery. METHOD: Fifteen patients who had no parenchymal lung disease were selected for control group and 15 patients who had parenchymal lung disease on non-dependent lung were selected for disease group. All patients had been intubated with double lumen endobronchial tubes and respiration was controlled with a rate of 14-15 breaths per minute and tidal volume 8 ml/kg. End-tidal and arterial carbon dioxide tension were measured at three different measurement periods (supine plus TLV, lateral decubitus plus TLV, lateral decubitus plus OLV). RESULTS: The arterial to end-tidal carbon dioxide tension difference was more increased in disease group than control group. But there was no significant difference in arterial to end-tidal carbon dioxide tension with position change, ventilation method change in each groups. CONCLUSION: We conclude that the arterial to end-tidal carbon dioxide tension difference is increased in lung disease, but it does not changed with position and ventilation method change.

Correlation between PaCO2 and PETCO2 during Laparoscopic Cholecystectomy / 대한마취과학회지

During the laparoscopic cholecystectomy, the ventilatory and hemodynamic changes could occur due to the peritoneal insufflation of CO2 as well as the position change. Various sults of the relationship between arterial and end-tidal PCO2 in different conditions have been reported. The authars studied to determine how closely end-tidal PCO2 reflects arterial PCO2 before, during, and after laparoscopic cholecystectomy. Peak inspiratory airway pressures, arterial blood pressures and heart rates were also measured simultaneously. Peritoneal insufflation of CO2 resulted in significant increase in peak inspiratory airway pressure and arterial blood pressure, but there were no significant changes in heart rates. Arterial and end-tidal PCO2 increased during laproscopy and, although there was no statistical significance in P(a-ET)CO2, P(a-ET)CO2 increased during laparoscopy and retumed to perinsufflation level after deflation of CO2. There was positive correlation between arterial and end-tidal PCO2 before CO2 insufflation, 10 minutes after CO2 insufflation and 10 minutes after deflation of CO2. However there was no correlation at 30 and 50 minutes after CO2 insufflation. These results suggested that the arterial PCO2 could not reflect end-tidal PCO2 exactly, and intermittent arterial blood gas studies should be warranted during laparoscopic cholecystectomy.

Acid-Base and Blood-Gas Status of Newborn Umbilical Blood according to Induction-Delivery and Uterine Incision-Delivery Intervals under General Anesthesia for Cesaeran Section / 대한마취과학회지

In cesarean section under general anesthesia, inhalation anesthetics may compound fetal acidosis brought by maternal hypoxia or uteroplacental insufficiency. The chance af fetal distress may be increased with prolonged induction-delivery (ID) and uterine incision-delivery (UD) intervals in such cases. These studies were undertaken to evaluate the changes of fetal acid-base and blood-gas status according to these intervals in 58 parturients given cesarean section under general anesthesia. 58 neonates were divided into three groups according to their ID interval [group 1 (N=26): less than 6 minutes, group 2 (N=25): 6 to 10 minutes, group 3 (N=7): 10 to 15 minutes] and four groups according to their UD interval[group A (N=25): less than 60 seconds, group B (N=22): 60 to 90 seconds, group C (N=9): 90 to 120 seconds, group D (N=2): 120 to 180 seconds]. The pH, PCO2, PO2 and HCO3 values of the umbilical vein blood at delivery in the groups 1, 2, 3 divided according to ID intervals were 7.37+/-0.03, 7.36+/-0.04, 7.36+/-0.03; 39.75+/-4.83, 41.76+/- 4.03, 38.81+/-2.31; 34.35+/-745, 32.65+/-9.63, 30.89+/-11.28 (in mmHg); and 23.21+/-0.33, 23.30+/-0.26, 22.15+/-0.52 (in mEq/L), respectively, and in groups A, B, C, D divided according to UD intervals, they were 7.37+/-0.02, 7.37+/-0.02, 7.37+/-0.03, 7.36+/-0.06; 40.30+/-5.20, 40,63+/-3.11, 39.96+/-4.42, 40.03 +/-5.09; 32.35+/-8.23, 31.82+/-0.17, 35.67+/-8.35, 33.53+/-10.53 (in mmHg); and 23.14+0.26, 23.60+/-0.36, 22.88+/-0.67, 23.35+/-0.35 (in mEq/L), respectively. No significant differences in these values were present between these ID- or UD- based groups.

The Relationship between End Tidal and Arterial Carbon Dioxide Tension during Endobronchial Anesthesia / 대한마취과학회지

The purpose of this study is to evaulate the relationship between end-tidal PCO2(PetCO2) and arterial PCO2(PaCO2) by placing patients from the supine to the lateraI decubitus position and by the changes from two lung ventilation(TLV) to one lung ventilation(OLV) during noncardiac thoracic surgery in 20 patients. All patients had been intubated with double-lumen endobronchial tubes and respirations were controlled with a rate of 14- l7 breaths per minute and tidal volume of 8 ml/kg by an anesthetic ventilator. End tidal PCO2 and arterial PCO2 were measured at three different measurement points(supine plus TLV, lateral decubitus plus TLV, and lateral decubitus plus OLV). End tidal PCO was obtained by mainstream infrared analysis, and arterial blood samples for arterial PCO2 were taken from the radial artery simultaneously. The results were as follows: l) The mean difference between arterial and end tidal carbon dioxide tension(Pa-etCO2) was 7.5+/-2.9mmHg at the supine position, TLV(r=0.76, P<0.01). 2) The mean Pa-etCO2 was 6.2+/-3.1 mmHg at the lateral decubitus position, TLV(r =0.68, P < O.ol ). 3) The mean Pa-etCO2 was 7.1+/-2.5 mmHg at the lateral decubitus position, OLV(r=0.85, P< 0.01). 4) The changes in Pa-etCO2 were very slight during thoracotomy and endobronchial anesthesia, these were of negligible clinical importance. We conclude that measurement of PetCO2 is reliable as a guideline of ventilation during endobronchial anesthesia.

Clinical Application of Self-developed Scavenger for Waste Anesthetic Gases Removal / 医疗卫生装备

Objective To evaluate the scavenging efficacy of a novel scavenger in removing isoflurane.Methods Forty five patients undergoing abdominal surgery were enrolled and randomly divided into three groups.The Datex-ohmeda S/5 anesthetic machine was applied to provide general anesthesia with isoflurane in group A,Datex-ohmed Aestiva/5 in group B,and Drager RA2S in Group C.After 60 minutes,the gas samples were taken at the waste gas outlet,airtake and airout of stripe tubes of anesthetic machines by Philips intellivue MP60 Anesthesia monitor to identify the concentrations of isoflurane and PCO2 both before and after the application of the scavenger.Results The novel scavenger could completely eliminate waste anesthetic gases including isoflurane and CO2.Conclusion The eliminating rate is 100% and the air quality in operating room is improved apparently.

End - tidal Carbon Dioxide Measurements in the Pediatric Patients : A Comparison of End - tidal PCO2 Sampled from the Proximal and Distal Ends of Pediatric Uncuffed Tracheal Tube / 대한마취과학회지

To determine the accuracy of end-tidal PCO2(PetCO2) measurement analysed with Ohmeda 5210 capnometer in the pediatric patients whose jung were ventilated with Ohio infant Circle Absorber and Ohio Ventilatior 7200, we compared PetCO2, measurements sampled from the proximal(PetCO2-p) and distal(PetCO2-d) ends of the tracheal tube to arterial PCO2(PaCO2) in 22 healthy pediatric patients between 6.8 to 18.5kg. The results were as follow: 1) Proximal PetCO2 and distal PetCO2 correlated with PaCO2(r=0.76%, SEE=2.79, r=0.70:SEE=3.01, respectively)(p<0.05). 2)Arterial to end-tidal PCO2 difference(delta(a-et)PCO2) was significantyly greater with distal(3.53+/-4.68 mmhg) than proximal(0.35+/-2.72 mmhg) sampling(p<0.05). 3) In subgroup of patients whose proximal to distal concentration of nitrous oxide difference was more than 2%, the delta(a-et)PCO2 using distal sampling(7.90+/-5.15 mmhg) was also significantly greater then it was using proximal sampling(-1.73+/-2.39 mmhg)(p<0.05).. We conclude that distal estimates of PetCO2-P can not provide accepatbale estimate of PaCO2 in healthy pediatric patients who are intubated with pediatric uncuffed tracheal tube.

Evaluation of Pulmonary Ventiation Effects about pH , ( a-Et )PCO2 , K+ between Normal and Hyperventilation with Capnometric Control / 대한마취과학회지

Capnometer has been used in anesthesia for the evaluation of pulmonary ventilation because of its nonivasive and continuous monitoring advantges. We studied pulmonary ventilation effects with arterial blood gas parameter between normoventilation and hyperventilation with capnometric control during 1 hr duration. We devided two group. Control group was maintained PetCO2 38 mmHg and experimental group PetCO2 28 mmHg and four times arterial blood gas sample were done. The results were as follows. 1) Serum K+ concentration was decreased siginifcantly in hyperventilation group. 2) Arterial pH changes were observed respiratory alkalosis in experimental group and respiratory acidosis in control group. 3) (a-t)PCO2 differnce were increased in both group and especially control group with correlation of time duration. 4) No arrhythmia were detected in both group. We conclude that only capnometric control of pulmonary ventilation is not suffieient and it has to be combined periodic ABGS and resetting of ventilation mode.