Aporte de fluidos en el pacientes pediátricos hospitalizados / Fluid intake in hospitalized pediatric patients

El aporte de fluidos constituye un elemento central en la atención del paciente pediátrico hospitalizado, existiendo aún controversias acerca de cuál es la composición óptima, la dosis adecuada y la mejor estrategia para administrar los mismos. El propósito de este artículo de actualización es brindar al médico que se desempeña en las diferentes áreas de la internación pediátrica, conceptos y enfoques terapéuticos que lo ayuden en la asistencia de los pacientes que por diversos motivos requieren la administración de fluidos endovenosos. La recomendación de utilizar cristaloides en la reanimación es casi uniforme. Se observa una clara tendencia al uso de soluciones isotónicas balanceadas para la reposición del déficit previo y el aporte de fluidos de mantenimiento. En relación a la dosis y a la estrategia, es generalizada la recomendación de un enfoque más restrictivo en el aporte de volumen, aún en los pacientes con shock, donde es necesario lograr un balance entre una resucitación efectiva y el riesgo de sobrecarga de fluidos. Respecto a la administración de albúmina al 20% en el paciente crítico con hipoalbuminemia, la evidencia existente es escasa y no permite formular recomendaciones. Sin embargo, es frecuente su uso en la práctica asistencial

Intravenous fluids administration is a central element in the care of hospitalized pediatric patients, and there are still controversies about what is the optimal composition, the appropriate dose, and the best strategy for their administration. The purpose of this narrative review is to provide the physicians who works in the different areas of pediatric hospitalization, concepts and therapeutic approaches that help them in the care of patients who for diverse reasons require administration of intravenous fluids. The recommendation to use crystalloids in resuscitation is almost uniform. There is a clear trend towards the use of balanced isotonic solutions to replace the previous deficit and the supply of maintenance fluids. In relation to the dose and strategy, the recommendation of a more restrictive approach in volume administration is generalized, even in patients with shock, where it is necessary to strike a balance between effective resuscitation and the risk of fluid overload. Regarding the administration of 20% albumin in critically ill patients with hypoalbuminemia, the existing evidence is scarce and does not allow recommendations to be formulated. However, it is frequently used in healthcare practice

Avaliação de soluções eletrolíticas e vias da administração sobre o teor de umidade das fezes de equinos desidratados experimentalmente / Evaluation of electrolyte solutions and administration routes on the moisture content of feces of experimentally dehydrated horses

A ocorrência de processos fisiopatológicos que cursam com desidratação da ingesta no trato gastrointestinal dos equinos é comum na rotina clínica. Fatores como diminuição da motilidade intestinal e sobrecarga intraluminal de conteúdo desidratado podem levar a compactação em segmentos como estômago, ceco e cólons. Este estudo objetivou realizar a comparação entre soluções eletrolíticas enterais hipotônica (SeHIPO) e isotônica (SeISO) e a solução Ringer com lactato de sódio (RL IV) sobre o teor de umidade das fezes de equinos submetidos a um período de desidratação experimental (PD). Foram utilizados seis equinos adultos, todas fêmeas com idades entre 10 e 15 anos, média de 440 kg de peso corpóreo. O PD constou de 36 horas de jejum hídrico e alimentar associadas a duas administrações intravenosas de furosemida, sendo a primeira imediatamente no início (T-36) e a segunda 12 horas após o início do PD. Os tratamentos utilizados foram: SeHIPO e SeISO, ambas administradas por via nasogástrica em fluxo contínuo (HETfc), e RL IV administrada pela via intravenosa. Todos os tratamentos foram administrados a uma taxa de infusão contínua de 15mL kg-1 h-1 durante 8 horas consecutivas. O delineamento experimental utilizado foi o crossover6x3, onde cada animal foi submetido, em sistema de rodízio, aos três tratamentos em momentos distintos. As soluções eletrolíticas enterais demonstraram maior eficácia na recomposição do teor de umidade das fezes quando comparadas à terapia RL IV. A hidratação enteral com soluções isotônicas e hipotônicas administrada em fluxo contínuo são eficazes em restaurar o teor de umidade das fezes, podendo ofertar uma opção econômica, segura e eficiente na reidratação de pacientes e nas afecções que cursam como obstruções intraluminais simples.

The occurrence of pathophysiological processes that curse with digesta dryness in the gastrointestinal tract of horses is common in clinical routine, factors such as decreased intestinal motility and intraluminal overload of dry content can lead to compaction in segments such as cecum and colon. This study aimed to compare a hypotonic enteral solution (SeHIPO), an isotonic enteral solution (SeISO) and a Ringer with sodium lactate solution (RL IV) over the moisture content of equine feces submitted to an experimental dehydration protocol. Six adult horses were used, all females aged between 10 and 15 years, average body weight of 440 kg. The PD consisted of a 36 hours period of water and food fasting associated with two intravenous administrations of furosemide, the first immediately at the beginning (T-36) and the second 12 hours after the beginning of the PD. The treatments used were: SeHIPO (hypotonic enteral solution administered via nasogastric), SeISO (enteral isotonic solution administered via nasogastric) and RL IV (Ringer's solution with sodium lactate administered intravenously), all treatments were administered by continuous infusion at a rate of 15mL kg-1 h-1 for 8 consecutive hours. The experimental design used was the 6x3 crossover, where each animal is submitted, in a rotation system, to the three treatments at different times. Enteral fluid therapy with isotonic and hypotonic solutions administered in continuous flow are effective in restoring the moisture content of feces, and may offer an economical, safe, and efficient option for rehydrating patients and in conditions that progress as simple intraluminal obstructions.

Maintenance enteral electrolyte solutions for neonatal calves: sodium acetate and osmolarity effects / Soluções eletrolíticas enterais de manutenção para bezerros neonatos: efeitos do acetato de sódio e da osmolaridade

The use of hypotonic electrolytic solutions in enteral fluid therapy is still understudied in calves. The objective of the present study was to evaluate the effects of maintenance enteral electrolytic solutions with different concentrations of sodium acetate and different osmolarities in calves. For this, 18 Holstein calves, six male and 12 female, 20 days old and weighing around 52kg, were used. The animals were randomly divided into three groups and each group received one of the treatments. The three electrolytic solutions contained the same components in different concentrations, resulting in a hyposmotic, an isosmotic and a hyperosmotic solution. Each animal was maintained in enteral fluid therapy for 12 hours with infusion rate of 15mL kg-1 h-1. Abdominal circumference, body weight, feces consistency, glucose and plasma lactate, pH, pCO2, HCO- 3 and BE were measured at the following times: T0h, T6h, T12h and T24h. The hyposmotic solution did not generate the onset of diarrhea, while the isosmotic and the hyperosmotic did. Regardless of the dose used, acetate did not cause metabolic alkalosis in the evaluated animals. The results suggest that the use of hyposmotic solution in diarrheic calves, dehydrated and without metabolic acidosis, may be clinically important.(AU)

O uso de soluções eletrolíticas hipotônicas na hidratação enteral ainda é pouco estudado em bezerros. O objetivo do presente estudo foi avaliar os efeitos de soluções eletrolíticas enterais de manutenção com diferentes concentrações de acetato de sódio e diferentes osmolaridades em bezerros. Para isso, foram utilizados 18 bezerros, seis machos e 12 fêmeas, holandeses, com 20 dias de nascidos e pesando por volta dos 52kg. Os animais foram divididos aleatoriamente em três grupos e cada grupo recebeu um dos tratamentos. As três soluções eletrolíticas continham os mesmos componentes, mas em diferentes concentrações, resultando em uma solução hiposmótica, uma isosmótica e uma hiperosmótica. Cada animal foi mantido em hidratação enteral durante 12 horas com taxa de infusão de 15mL kg-1h-1. Foram aferidos perímetro abdominal, peso corporal, consistência das fezes, glicose e lactato plasmático, pH, pCO2, HCO- 3 e excesso de base nos seguintes tempos: T0h, T6h, T12h e T24h. A solução hiposmótica não gerou aparecimento de diarreia, enquanto a isosmótica e a hiperosmótica geraram. Independentemente da dose utilizada, o acetato não causou alcalose metabólica nos animais avaliados. Os resultados sugerem que o uso da solução hiposmótica em bezerros diarreicos, desidratados e sem acidose metabólica, pode ser clinicamente importante.(AU)

Hypotonic enteral electrolyte solutions administered by nasoesophageal tube in continuous flow in dogs dehydrated by water restriction: Part 1 / Soluções eletrolíticas enterais hipotônicas administradas por sonda nasoesofágica em fluxo contínuo em cães desidratados por restrição hídrica: Parte 1

The present study assessed and compared the effects of hypotonic enteral electrolyte solutions administered by nasoesophageal tube in continuous flow in dogs submitted to water restriction on packed cell volume; total serum protein and serum osmolarity concentrations; blood volume; plasma glucose and lactate levels; blood gas analysis, anion gap, and strong ion difference. Six adult dogs were used (four males and two females). All animals were submitted to both proposed treatments in a crossover design 6×2. The treatments were as follows: ESmalt consisting of 5g sodium chloride, 1g potassium chloride, 1g calcium acetate, 0.2g magnesium pidolate, and 9.6g maltodextrin that were diluted in 1.000mL water (measured osmotic concentration of 215mOsm L−1) and ESdext consisting of 5g sodium chloride, 1g potassium chloride, 1g calcium acetate, 0.2g magnesium pidolate, and 9.6g dextrose that were diluted in 1.000mL water (measured osmotic concentration of 243mOsm L−1). All solutions were administered at 15ml kg−1 h−1 for 4 hours. Both solutions increased the plasma volume in dehydrated dogs without causing adverse effects. However, ESmalt was more effective in promoting the increase in blood volume.(AU)

O presente estudo avaliou e comparou os efeitos de soluções eletrolíticas enterais hipotônicas, administradas por sonda nasoesofágica em fluxo contínuo em cães submetidos a restrição hídrica, sobre o hematócrito, proteínas totais séricas, osmolaridade sérica, volemia, glicose e lactato plasmáticos, hemogasometria, ânion gap e DIF. Foram utilizados seis cães adultos (quatro machos e duas fêmeas). Todos os animais foram submetidos aos dois tratamentos propostos, em um delineamento crossover 6×2. Os tratamentos foram os seguintes: SEmalt - 5g de cloreto de sódio, 1g de cloreto de potássio, 1g de acetato de cálcio, 0,2g de pidolato de magnésio e 9,6g de maltodextrina, diluídos em 1.000mL de água (osmolaridade mensurada: 215mOsm L -1 ); SEdext - 5g de cloreto de sódio, 1g de cloreto de potássio, 1g de acetato de cálcio, 0,2g de pidolato de magnésio e 9,6g de dextrose, diluídos em 1.000mL de água (osmolaridade mensurada: 243mOsm L -1 ). Todas as soluções foram administradas no volume de 15mL kg -1 hora -1 , durante quatro horas, em fluxo contínuo. Ambas as soluções aumentaram o volume plasmático em cães desidratados, sem gerar o aparecimento de efeitos adversos. Porém, a SEmalt foi mais eficaz em promover a expansão da volemia.

Avaliação comparativa entre diferentes modalidades de reposição hidroeletrolítica em equinos desidratados experimentalmente pela utilização de parâmetros do exame físico e marcadores hematológicos / Comparative evaluation between different kinds of hydroeletrolitic reposition in horses experimentally dehydrated by the use of physical examination parameters and hematological markers

O objetivo do presente estudo foi realizar a comparação entre três modalidades de terapias hidroeletrolíticas, sendo uma hipotônica (SeHIPO) e outra isotônica (SeISO), ambas por via enteral em fluxo contínuo (HETfc), com a solução de ringer lactato por via intravenosa (RL IV), na taxa de infusão de 15 ml/kg/h, administradas simultaneamente em tempo real por 8 horas num delineamento crossover6X3 em equinos desidratados experimentalmente pela utilização de parâmetros clínicos do exame físico e de alguns exames laboratoriais. Para tanto foram utilizadas 6 éguas adultas da raça Brasileiro de Hipismo submetidas a um protocolo experimental de indução de desidratação (PD) e posteriormente tratadas de acordo com o delineamento experimental. Os resultados obtidos demonstraram que ambos os tratamentos HETfc demonstraram eficácia equivalente ao RL IV na reversão dos efeitos determinados pelo PD, ainda que para os marcadores da volemia, tais como o Volume Globular (VG), Proteínas Plasmáticas Totais (PPT) e porcentagem de Volume Plasmático (%VP) tenham sido relativamente mais lentos. Porém, para os demais marcadores clínicos a eficácia entre as três terapias estudadas foi equivalente. Esses resultados comprovam a ação das terapias HETfc ao serem comparadas ao tratamento RL IV, pela utilização dos marcadores clínicos e laboratoriais utilizados, e justificam a indicação e utilização dessas modalidades terapêuticas em equinos.

The objective of the present study was to compare three modalities of hydroelectrolytic therapies, one hypotonic (SeHIPO) and another isotonic (SeISO), both by continuous enteral flow (HETfc), with intravenous lactated ringer solution ( RL IV), at the infusion rate of 15 ml / kg / h, administered simultaneously in real time for 8 hours in a 6X3 crossover design in horses experimentally dehydrated by the use of clinical parameters of the physical examination and some laboratory tests. Six adult mares of the Brazilian Equestrian race were submitted to an experimental protocol for induction of dehydration (PD) and later treated according to the experimental design. The results showed that both HETfc treatments demonstrated an efficacy equivalent to RL IV in the reversal of the effects determined by PD, although for volume markers such as Globular Volume (VG), Total Plasma Proteins (PPT) and Percentage of Plasmatic Volume (% VP) were relatively slower. However, for the other clinical markers the efficacy among the three therapies studied was equivalent. These results confirm the action of HETfc therapies when compared to RL IV treatment, by the clinical and laboratorial markes used, and justify the indication and use of these therapeutic modalities in horses.

Hiponatremia adquirida en el hospital: ¿influye el tipo de fluidoterapia en los niños ingresados a cuidados intensivos? / Hospital-acquired hyponatremia: Does the type of fluid therapy affect children admitted to intensive care?

Resumen: Introducción: Este estudio tuvo por objetivo valorar las diferencias entre el tipo de fluidoterapia ini cial utilizada (sueros isotónicos o hipotónicos) en el desarrollo de hiponatremia, valores de cloro y to lerancia de las vías venosas. Pacientes y Método: Estudio retrospectivo de cohortes en una Unidad de Cuidados Intensivos Pediátricos (UCIP) de un hospital terciario. Se incluyeron niños menores de 15 años ingresados durante el primer semestre de los años 2010 y 2013, que recibieron fluidoterapia in travenosa, excluyéndose los sometidos a cirugía cardiaca, trasplantados renales y aquellos con ingreso inferior a 24 h. Se recogieron datos epidemiológicos, de comorbilidad y relacionados con el ingreso, tipo de suero recibido, valores de sodio y cloro en las primeras 72 h y la incidencia de extravasaciones de vías periféricas. Resultados: Se incluyeron 111 niños: 68 (61,3%) recibieron líquidos hipotónicos y 43 (38,7%) isotónicos. No hubo diferencias respecto a la patología y gravedad, ni tampoco en el volumen de líquidos recibido. Entre los pacientes que recibieron sueros hipotónicos, 28 (41,2%) pre sentaron hiponatremia, siendo esta moderada (Na <130 mEq/kg) en 11 de ellos, en comparación con 8 niños (18,6%) entre los que recibieron sueros isotónicos, registrando hiponatremia moderada solo en un caso (p=0,027). No se registró ningún caso de hipernatremia, ni hubo diferencias en los valores de cloro plasmático. Tampoco se objetivó mayor frecuencia de pérdida del acceso venoso utilizando la fluidoterapia isotónica (4,7% vs. 7,4%, p=0,704). Conclusión: El uso de líquidos iniciales isotóni cos en niños hospitalizados en UCIP se asocia con menor incidencia y gravedad de hiponatremia, sin cambio en la cloremia y es bien tolerado por las vías venosas periféricas.

Abstract: Introduction: The objective of this study was to evaluate the association between the type of initial fluid therapy used (isotonic or hypotonic solutions) and the development of hyponatremia, the plas ma chlorine values and the tolerance of venous access. Patients and Method: Retrospective cohort study in a Pediatric Intensive Care Unit (PICU) of a high complexity hospital. There were included children younger than 15 years old hospitalized during the first semester of 2010 and 2013 who recei ved intravenous maintenance fluid therapy, excluding patients undergoing cardiac surgery, kidney transplant and admissions that lasted less than 24 hours. Epidemiological, comorbidity and admis sion-related data were collected, including type of solution received, sodium and chlorine values in the first 72 hours of hospitalization and the incidence of extravasation of peripheral intravenous lines. Results: 111 children were included; 68 children (61.3%) were treated with hypotonic solutions and 43 (38.7%) with isotonic solutions. There were no differences in pathology and severity, and also in the volume of fluid received. Among the patients who received hypotonic solutions, 28 (41.2%) de veloped hyponatremia, wich was moderate (Na <130 mEq/Kg) in 11 cases, compared with 8 children (18.6%) who received isotonic solutions, with only one case of moderate hyponatremia (p = 0.027). No cases of hypernatremia were recorded, and there were no differences in plasma chlorine values. There was also no increased frequency of venous access loss in patients treated with isotonic solutions (4.7% versus 7.4%, p = 0.704). Conclusion: Treatment with initial isotonic solutions in children hos pitalized in PICU is associated with a lower incidence and severity of hyponatremia, without changes in the plasma chlorine values and it is well tolerated by peripheral intravenous lines.

Protein kinase C enhances the swelling-induced chloride current in human atrial myocytes / 华中科技大学学报（医学）（英德文版）

Swelling-activated chloride currents (ICl.swell) are thought to play a role in several physiologic and pathophysiologic processes and thus represent a target for therapeutic approaches. However, the mechanism of ICl.swell regulation remains unclear. In this study, we used the whole-cell patch-clamp technique to examine the role of protein kinase C (PKC) in the regulation of ICl.swell in human atrial myocytes. Atrial myocytes were isolated from the right atrial appendages of patients undergoing coronary artery bypass and enzymatically dissociated. ICl.swell was evoked in hypotonic solution and recorded using the whole-cell patch-clamp technique. The PKC agonist phorbol dibutyrate (PDBu) enhanced ICl.swell in a concentration-dependent manner, which was reversed in isotonic solution and by a chloride current inhibitor, 9-anthracenecarboxylicacid. Furthermore, the PKC inhibitor bis-indolylmaleimide attenuated the effect and 4α-PDBu, an inactive PDBu analog, had no effect on ICl.swell. These results, obtained using the whole-cell patch-clamp technique, demonstrate the ability of PKC to activate ICl,swell in human atrial myocytes. This observation was consistent with a previous study using a single-channel patch-clamp technique, but differed from some findings in other species.

Comparison of two maintenance electrolyte solutions in children in the postoperative appendectomy period: a randomized, controlled trial / Comparação de duas soluções para manutenção hidroeletrolítica no pós-operatório de apendicectomia em crianças: um estudo controlado e randomizado

ABSTRACT OBJECTIVE: To compare two electrolyte maintenance solutions in the postoperative period in children undergoing appendectomy, in relation to the occurrence of hyponatremia and water retention. METHODS: A randomized clinical study involving 50 pediatric patients undergoing appendectomy, who were randomized to receive 2,000 mL/m2/day of isotonic (Na 150 mEq/L or 0.9% NaCl) or hypotonic (Na 30 mEq/L NaCl or 0.18%) solution. Electrolytes, glucose, urea, and creatinine were measured at baseline, 24 h, and 48 h after surgery. Volume infused, diuresis, weight, and water balance were analyzed. RESULTS: Twenty-four patients had initial hyponatremia; in this group, 13 received hypotonic solution. Seventeen patients remained hyponatremic 48 h after surgery, of whom ten had received hypotonic solution. In both groups, sodium levels increased at 24 h (137.4 ± 2.2 and 137.0 ± 2.7 mmol/L), with no significant difference between them (p = 0.593). Sodium levels 48 h after surgery were 136.6 ± 2.7 and 136.2 ± 2.3 mmol/L in isotonic and hypotonic groups, respectively, with no significant difference. The infused volume and urine output did not differ between groups during the study. The water balance was higher in the period before surgery in patients who received hypotonic solution (p = 0.021). CONCLUSIONS: In the post-appendectomy period, the use of hypotonic solution (30 mEq/L, 0.18%) did not increase the risk of hyponatremia when compared to isotonic saline. The use of isotonic solution (150 mEq/L, 0.9%) did not favor hypernatremia in these patients. Children who received hypotonic solution showed higher cumulative fluid balance in the preoperative period.

RESUMO OBJETIVO: Comparar duas soluções de manutenção hidroeletrolítica no período pós-operatório (PO) de crianças submetidas à apendicectomia quanto à ocorrência de hiponatremia e retenção hídrica. MÉTODOS: Estudo clínico randomizado que envolveu 50 pacientes pediátricos submetidos à apendicectomia, randomizados para receber 2.000 ml/m2/dia de solução isotônica (Na 150 mEq/L ou NaCl 0,9%) ou hipotônica (Na 30mEq/L ou NaCl 0,18%). Eletrólitos, glicose, ureia e creatinina foram mensurados no início do estudo, 24 e 48 horas após a cirurgia. Foram analisados volume infundido, diurese, peso e balanço hídrico. RESULTADOS: Apresentaram hiponatremia inicial 24 pacientes. Desses, 13 receberam solução hipotônica. Dezessete pacientes permaneceram hiponatrêmicas 48 horas após a cirurgia, 10 haviam recebido solução hipotônica. Nos dois grupos os níveis de sódio aumentaram na 24ª hora PO (137,4 ± 2,2 e 137,0 ± 2,7) e não houve diferença entre eles (p = 0,593). Níveis de sódio 48 h após a cirurgia foram 136,6 ± 2,7 e 136,2 ± 2,3 no grupo isotônico e hipotônico respectivamente sem diferença significativa. Os volumes infundidos e a diurese não diferiram entre os grupos durante o estudo. O balanço hídrico foi maior no período anterior à cirurgia no grupo de pacientes que receberam solução hipotônica (p = 0,021). CONCLUSÕES: No período pós-apendicectomia, o uso da solução hipotônica não aumentou o risco de hiponatremia quando comparado com uma solução salina isotônica. O uso da solução isotônica não favoreceu a hipernatremia nesses pacientes. Crianças que receberam solução hipotônica apresentaram maior balanço hídrico cumulativo no período pré-operatório.

Pediatric surgical patients; comparison of the effects of balanced salt solution with 1% dextrose and pead's solution on blood glucose and sodium levels intra operatively

Almost all the Pediatric surgeons and most of pediatric anesthetists are adhered to traditional paed's solution against recommendations due to fear of hypoglycaemia and not being aware of hyponatremia. To compare the effects of balanced salt solution with1% dextrose and Read's solution on blood glucose and sodium levels in pediatric surgical patients intra operatively. Interventional quasi experimental study. Department of Anesthesia, Intensive care and pain medicine in Sheikh Zayed Medical College/ Hospital Rahim Yar Khan [Pakistan]. December 2014 to February 2015. 60 patients were enrolled and divided into equal groups named after their respective iv fluids i.e.'Read's Solution' and [RLD1]. Patients aged between 1 month and 08 years, without gender discrimination, with ASA 1,2, fasted according to ASA guidelines undergoing elective surgical procedure general anesthesia were included in this study. Blood sampling for levels of serum sodium and glucose was done pre-operatively and 01 hour post-operatively. In immediate post-operative period incidence of hyperglycemia was statistically higher in 'Read's Solution' group [93.3%;28/30] vs 'RLD1' group [10%;3/30] p=0.000. Relative risk was 9.3 in 'Read's Solution' compared with 'RLD1' solution. Hyponatremia was statistically higher in 'Read's Solution' group [56.6%; 17/30] than in'RLDI' group [16.6%;5/30] p=0.001. Relative risk was 3.4 in 'Read's Solution' compared with 'RLD1' solution. Hypoglycemia and hypernatremia were not found in any patient in either group. Our results reflected that 'RLDI'is a better option than 'Read's Solution' as it is less likely to cause hyponatremia and doesnot cause hypoglycemia. However a large number of clinical trials in almost every teaching hospital are required to convince pediatric surgeons and anesthetists to use evidence based solutions

Effect of a new remineralizing biomaterial on the color of dental enamel

El objetivo de este trabajo fue describir el efecto de la composición de una sustancia remineralizante (SRM) y de la presión osmótica sobre el color dental mediante espectrofotometría. Se tomaron 104 premolares y molares humanos repartidos aleatoriamente en 2 grupos, cada uno de 52 especímenes. El grupo 1 se trató con la sustancia remineralizante SRM 55 (agente remineralizante 1) mezcla de 50 por ciento - 50 por ciento de mineral de grano fino y otro mineral de grano grueso y el grupo 2 se trató con la sustancia remineralizante SRM 91(agente remineralizante 2) contienen los mismos minerales en proporción 90 por ciento - 10 por ciento. A su vez cada grupo se dividió en 2 subgrupos, cada uno de 26 especímenes que se almacenaron así: Un subgrupo en saliva sintética con presión osmótica isotónica (PI) y el otro con presión osmótica hipotónica (PH). Se tomaron registros iniciales y finales con el espectrofotómetro Vita Easy Shade®. Con las lecturas se calcularon losparámetros de color (L*; a*; b*) y los índices de blanqueamiento (WIC; WIO; W). Los cambios de color (ΔL; ΔA; ΔB; yΔE) y los índices de blanqueamiento se compararon y se trataron todos mediante un análisis descriptivo. Las variables ΔA, ΔL, ΔB, ΔE e índice de blanqueamiento W se trataron con ANOVA y los índices WIC y WIO con un análisis de varianza no paramétrico Kruskal Wallis. Los resultados indican que la combinación A2 (SRM 91 y PI) afectó las variables ΔB y ΔE. La combinación B1 (SRM 55 Y PH) afectó las variables ΔA, ΔB y el índice de blanqueamiento WIO. Solamente SRM 91afectó la variable ΔL. La presión osmótica de la saliva y la sustancia remineralizante afectan el color del esmalte dental...

Efeito de soluções eletrolíticas enterais com diferentes osmolaridades sobre o perfil eletrolítico e bioquímico de equinos / Horses treated with enteral electrolyte solutions with differents osmolarities

Foram comparados os efeitos de soluções eletrolíticas com diferentes osmolaridades administradas via enteral por sonda nasoesofágica de pequeno calibre, em fluxo contínuo, sobre o perfil bioquímico em equinos. Foram utilizadas seis fêmeas adultas em dois quadrados latinos 6x3 simultâneos em modelo misto. Os animais foram distribuídos em três grupos e cada grupo submetido aos seguintes tratamentos: HipoMalt - 5g de cloreto de sódio, 0,5g de cloreto de potássio, 0,2g de pidolato de magnésio, 1g de gluconato de cálcio e 10g de maltodextrina diluídos em 1.000mL de água (181mOsmol L-1), HipoDext - 5g de cloreto de sódio, 0,5g de cloreto de potássio, 0,2g de pidolato de magnésio, 1g de gluconato de cálcio e 10g de dextrose diluídos em 1.000mL de água (228mOsmol L-1) e IsoProp - 5g de cloreto de sódio, 0,5g de cloreto de potássio, 0,2g de pidolato de magnésio e 10g de propionato de cálcio diluídos em 1.000mL de água (282mOsm L-1). As soluções contendo dextrose (HipoDext) e maltodextrina (HipoMalt) foram mais eficazes em aumentar a taxa glicêmica sem ocasionar desequilíbrio eletrolítico. Já o tratamento com propionato de cálcio (IsoProp) além de aumentar o lactato plasmático não teve efeito sobre a glicemia.

We compared the effects of electrolyte solutions with different osmolarities administered through enteral route by naso-esophageal probe of small-caliber with continuos flow on the electrolytic and biochemical profile in horses. Six adult females were used in two simultaneous 6x3 Latin squares mixed model. The animals were divided into three groups and received the following treatments: HipoMalt - 5g of sodium chloride, 0.5g of potassium chloride, 0.2g of magnesium pidolate, 1g of calcium gluconate and 10g of maltodextrin diluted in 1.000mL of water (181mOsmol L-1); HipoDext - 5g of sodium chloride, 0.5g of potassium chloride, 0.2g of magnesium pidolate, 1g of calcium gluconate and 10g of dextrose diluted in 1.000mL of water (228mOsmol L-1); IsoProp - 5g of sodium chloride, 0.5g of potassium chloride, 0.2g of magnesium pidolate, 1g of calcium gluconate and 10g of calcium propionate diluted in 1.000mL of water (282mOsm L-1). The hypotonic electrolyte solutions containing dextrose (HipoDext) and maltodextrin (HipoMalt) were more effective in increase the rate glucose without causing electrolyte imbalance. Treatment with calcium propionate (IsoProp) besides increasing plasma lactate had no effect on blood glucose.

Ensayo clínico aleatorizado sobre la administración de una solución de mantenimiento intravenosa hipotónica comparada contra una isotónica en pacientes pediátricos críticos: a randomized control trial / Hypotonic versus isotonic maintenance fuids in critically ill pediatric patients

Introducción. Las soluciones hipotónicas se han vinculado a la producción de hiponatremia iatrogénica. Objetivos. Evaluar las variaciones en el sodio sérico (NaS) tras la administración de una solución de mantenimiento intravenosa isotónica (NaCl al 0,9% en dextrosa al 5%) en comparación con una solución de mantenimiento hipotónica (NaCl al 0,45% en dextrosa al 5%). Material y métodos. Ensayo clínico aleatorizado, doble ciego y controlado. Se enrolaron pacientes pediátricos con una estadía esperada en la unidad de cuidados intensivos mayor de 24 horas, NaS normal y líquidos intravenosos > 80% de los líquidos totales de mantenimiento. La concentración sérica de Na se midió antes de colocar la solución de mantenimiento y al reducir la administración de ésta a < 80% del total del aporte. Resultados. Se incorporaron 63 pacientes, que fueron asignados en forma aleatoria a recibir una solución de mantenimiento hipotónica (n= 32) o isotónica (n= 31). Las características basales fueron similares en ambos grupos. No hubo diferencias con respecto a la cantidad de solución administrada (grupo hipotónico 865 ± 853 ml; grupo isotónico 778 ± 649 ml, p= 0,654) o el tiempo de infusión (grupo hipotónico: 24 ± 10,8 horas; grupo isotónico: 27,6 ± 12,8 horas, p= 0,231). Se encontró una diferencia en el NaS luego de la administración de las soluciones de mantenimiento (grupo hipotónico: 137,8 ± 4,3 mmol/L; grupo isotónico: 140,0 ± 4,1 mmol/L, p= 0,04). Ninguna de las dos soluciones de mantenimiento aumentó el riesgo de hiponatremia (Na 145 mmol/L). Conclusiones. Ambas soluciones de mantenimiento, en 24 horas de infusión, no aumentaron el riesgo de producir hiponatremia iatrogénica.

Introduction. Hypotonic fluids have been associated with the development of iatrogenic hyponatremia. Objectives. To assess variations in serum sodium (sNa) following the intravenous administration of isotonic maintenance fuids (0.9% NaCl/5% dextrose) compared to hypotonic maintenance fuids (0.45% NaCl/5% dextrose). Material and Methods. Randomized, controlled, double-blind clinical trial. Pediatric patients with an expected length of stay in the intensive care unit of more than 24 hours were enrolled, with normal serum Na, and IV fuids >80% of total maintenance fuids. Serum Na level was measured before administering maintenance fuids and when reducing the administration to <80% of total fuids. Results. The study included 63 patients who were randomly assigned to receive hypotonic (n= 32) or isotonic (n= 31) maintenance fuids. Baseline characteristics were similar in both groups. There were no differences in terms of volume of fuid administered (hypotonic group: 865 ± 853 mL; isotonic group: 778 ± 649 mL; p= 0.654) or infusion duration (hypotonic group: 24 ± 10.8 hours; isotonic group: 27.6 ± 12.8 hours; p= 0.231). A difference was found in the serum Na following the administration of maintenance fuids (hypotonic group: 137.8 ± 4.3 mmol/L; isotonic group: 140.0 ± 4.1 mmol/L, p= 0.04). None of these two maintenance fuids increased the risk of hyponatremia (Na 145 mmol/L). Conclusions. Neither hypotonic nor isotonic maintenance fluids increased the risk of developing iatrogenic hyponatremia with the 24 hour infusion.

Hypotonic versus isotonic maintenance fluids in critically ill pediatric patients: a randomized controlled trial / Hypotonic versus isotonic maintenance fluids in critically ill pediatric patients: a randomized controlled trial.

INTRODUCTION: Hypotonic fluids have been associated with the development of iatrogenic hyponatremia. OBJECTIVES: To assess variations in serum sodium (sNa) following the intravenous administration of isotonic maintenance fluids (0.9

dextrose) compared to hypotonic maintenance fluids (0.45

dextrose). MATERIAL AND METHODS: Randomized, controlled, double-blind clinical trial. Pediatric patients with an expected length of stay in the intensive care unit of more than 24 hours were enrolled, with normal serum Na, and IV fluids >80

of total maintenance fluids. Serum Na level was measured before administering maintenance fluids and when reducing the administration to <80

of total fluids. RESULTS: The study included 63 patients who were randomly assigned to receive hypotonic (n= 32) or isotonic (n= 31) maintenance fluids. Baseline characteristics were similar in both groups. There were no differences in terms of volume of fluid administered (hypotonic group: 865 ± 853 mL; isotonic group: 778 ± 649 mL; p= 0.654) or infusion duration (hypotonic group: 24 ± 10.8 hours; isotonic group: 27.6 ± 12.8 hours; p= 0.231). A difference was found in the serum Na following the administration of maintenance fluids (hypotonic group: 137.8 ± 4.3 mmol/L; isotonic group: 140.0 ± 4.1 mmol/L, p= 0.04). None of these two maintenance fluids increased the risk of hyponatremia (Na 145 mmol/L). CONCLUSIONS: Neither hypotonic nor isotonic maintenance fluids increased the risk of developing iatrogenic hyponatremia with the 24 hour infusion.

Solução salina isotônica como fluidoterapia de manutenção intravenosa para prevenir hiponatremia adquirida em crianças hospitalizadas / Isotonic saline solution as maintenance intravenous fluid therapy to prevent acquired hyponatremia in hospitalized children

OBJETIVOS: Avaliar se o uso de soluções salinas hipotônicas como fluidoterapia de manutenção em crianças hospitalizadas aumenta o risco de hiponatremia, se a administração de fluidos isotônicos é capaz de proteger contra a hiponatremia adquirida e se as soluções isotônicas aumentam os riscos de efeitos deletérios como hipernatremia ou sobrecarga hídrica. FONTES DOS DADOS: Realizou-se uma pesquisa bibliográfica nas bases de dados PubMed (01/01/1969 a 13/07/2011), Embase (1989 a 2011) e Cochrane Library (1989 a 2011). Adicionalmente, referências foram incluídas dos estudos selecionados. SÍNTESE DOS DADOS: Crianças hospitalizadas têm riscos potenciais para hiponatremia, e o uso de soluções salinas hipotônicas é o principal fator de risco para esse agravo. As soluções salinas isotônicas têm mostrado efeito protetor para hiponatremia e, até o momento, sem efeitos deletérios significativos, como sobrecarga hídrica, hipernatremia ou flebites. CONCLUSÕES: As evidências indicam que a tradicional recomendação de Holliday & Segar quanto à fluidoterapia de manutenção para crianças doentes e hospitalizadas merece ser reconsiderada em virtude das evidências sobre os efeitos adversos dela advindos, assim como dos melhores resultados obtidos com o emprego das soluções isotônicas.

OBJECTIVES: This review aims to evaluate if the use of hypotonic saline solutions as maintenance intravenous fluid therapy in hospitalized children increases the risk of hyponatremia, if the administration of isotonic fluids is able to protect against acquired hyponatremia and if the isotonic solutions increase the risks of deleterious effects such as hypernatremia or fluid overload. SOURCES: We researched the relevant literature on the PubMed (Jan 01 1969 to Jul 13 2011), EMBASE (1989 to 2011) and Cochrane Library (1989 to 2011) databases. Furthermore, references of selected studies were included. SUMMARY OF THE FINDINGS: Hospitalized children are potentially at risk of developing hyponatremia and the use of hypotonic saline solutions is the main risk factor for this disease. Isotonic saline solutions have shown a protective effect against hyponatremia, and, so far, there have been no significant deleterious effects such as fluid overload, hypernatremia or phlebitis. CONCLUSIONS: The evidence found indicates that the traditional recommendation of Holliday and Segar to use maintenance fluid therapy for sick and hospitalized children deserves to be reconsidered due to the adverse effects found to arise from it, apart from the better results obtained by using isotonic solutions.

Ca(2+)-dependent potassium channels play important roles in regulatory volume decrease in human nasopharyngeal carcinoma cells / 生理学报

It has been shown that cell volume regulation mechanisms play important roles in various cell functions. We demonstrated previously that volume-activated chloride channels were involved in cell volume regulation. The present study aimed to clarify the roles of various types of potassium channels in regulatory volume decrease (RVD) induced by hypotonic challenges in human nasopharyngeal carcinoma cells (CNE-2Z cells). The whole-cell patch clamp technique was used to record hypotonic challenge-induced potassium currents. During current recordings, cells were held at 0 mV and stepped to +/-46 and +/-92 mV, repeatedly. The cell volume was computed from cell diameters. The changes of cell volume were monitored and analyzed by the time-lapse imaging technique. The results showed that the exposure to 160 mOsm/L hypotonic solution caused the cells to swell by (144.5+/-4.2)%, activated a potassium current (59.2 pA/pF+/-13.3 pA/pF at 92 mV), and induced RVD. Cell volume was recovered from hypotonic challenge-induced swelling by (48.9+/-4.6)% after 20 min. The potassium current (at 92 mV) and RVD were inhibited by the calcium-dependent potassium channel blocker, clotrimazole (100 mumol/L), by (98.5+/-2.8)% and (89.3+/-4.9)%, respectively. Depletion of extracellular calcium prevented the activation of the hypotonic challenge-induced potassium current and inhibited the process of RVD. The voltage-gated potassium channel blocker, 4-AP (5 mmol/L), partially inhibited the hypotonic challenge-activated potassium currents by (66.6+/-5.3)% (at 92 mV). These results suggest that the Ca(2+)-dependent potassium channel is the main component of volume-activated potassium channels and plays an important role in volume regulation of CNE-2Z cells. The voltage-gated potassium channels may also contribute in part to the formation of the volume-activated potassium current.

Protective effect of hypotensive fluid resuscitation against lung ischemia-reperfusion injury in pregnant rabbits with uncontrolled hemorrhagic shock / 南方医科大学学报

<p><b>OBJECTIVE</b>To evaluate the effects of different fluid resuscitation strategies on superoxide dismutase (SOD), malondialdehyde (MDA) and myeloperoxidase (MPO) activities in the lung tissue in pregnant rabbits with uncontrolled hemorrhagic shock.</p><p><b>METHODS</b>Thirty pregnant New Zealand rabbits were randomized into 5 equal groups, namely the sham shock.(SS) group, shock group without interventions (SH group), and hemorrhagic shock groups with conventional normal saline (NS) resuscitation, NS hypotensive resuscitation, and hypertonic hyperosmotic hypotensive resuscitation (NS, NH, HHH groups, respectively) 30 min after the shock. At the end of the experiment, the rabbits were sacrificed, and the lungs were taken for detection of MDA, MPO and SOD levels.</p><p><b>RESULTS</b>Ischemia-reperfusion injury of the lungs in uncontrolled hemorrhagic shock resulted in decreased SOD and increased MDA and MPO contents. The MDA and MPO contents in HHH group were significantly lower than those in NH group, and both the groups, MDA and MPO contents were significantly lower than those of NS group (P<0.05). SOD activity was significantly higher in HHH group than in NH group (P<0.05).</p><p><b>CONCLUSION</b>In pregnant rabbits with uncontrolled hemorrhagic shock, hypotensive resuscitation more effectively ameliorates ischemia-reperfusion injuries in the lungs than aggressive fluid resuscitation, and hyperosmotic crystalloid and hyperonoctic colloid resuscitation provide significant protective effects against such injuries.</p>

Ion channel mechanism of regulatory volume decrease in human epithelial cells / 中国应用生理学杂志

<p><b>AIM</b>To observe the regulatory volume decrease (RVD) process of human intestine cells and investigate its ion channel mechanism.</p><p><b>METHODS</b>Cultured human intestine cells were exposed to hypotonic solution and the cell volume was measured using Coulter Counter System. RT-PCR was explored to detect the mRNA expression of Ca(2+) -activated K+ channel.</p><p><b>RESULTS</b>Human intestine cells showed a RVD process and this process could be blocked by Cl- channel blocker NPPB and K+ channel blocker TEA. Further results demonstrated the subtype of K+ channel involved in RVD was an intermediate-conductance, Ca(2+) -activated K+ channel (IK) because of its high sensitivity to clotrimazole. RT-PCR results also showed the expression of IK in this cell line.</p><p><b>CONCLUSION</b>The RVD process of intestine cell was dependent on the parallel activation of Cl- channel and K+ channel. The subtype of K+ channel in volved in the RVD process was IK channel.</p>

A randomized double-blind controlled trial comparing two forms of enema for flexible sigmoidoscopy.

OBJECTIVE: To compare bowel preparation quality and patient tolerance of two common enema solutions for flexible sigmoidoscopy. MATERIAL AND METHOD: Three hundred adults were randomized to receive a hypertonic sodium chloride or hypertonic sodium phosphate enema regime, each consisting of two enemas administered 60 and 30 min before the procedure. Patients completed surveys on preparation comfort. Patients and endoscopist were blinded to the preparation used During the procedure, the endoscopist took pictures of the mucosa and intraluminal content. All pictures were later evaluated by a single doctor who graded the quality of the preparation. RESULTS: There were no serious complications during or following the procedures. The preparation quality was rated as excellent or good by 76.9% of the hypertonic sodium chloride group and 72.9% of the hypertonic sodium phosphate group (p = 0.423). The hypertonic sodium chloride enema was associated with more abdominal discomfort (p = 0.018). CONCLUSION: Both enemas were safe for all patients with no statistical difference between the qualities of the two bowel preparations. Both preparations performed their bowel-cleaning function well and were suitable for the preparation of patients before flexible sigmoidoscopy. The less expensive hypertonic sodium chloride solution may be an option for hospitals where budgetary considerations are important.

Manutenção parenteral de líquidos na criança agudamente doente / Maintenance parenteral fluids in the critically ill child

OBJETIVO: Examinar as necessidades hídricas (água livre de eletrólitos) a serem consideradas quando da administração de fluidos de manutenção na criança em estado grave. Analisamos algumas das dificuldades na estimativa desses requisitos, e discutimos as controvérsias a respeito das recomendações tradicionais. FONTES DOS DADOS: MEDLINE (1966-2007),Embase (1980-2007), e Cochrane Library, usando os termos: “fluidoterapia”, “solução hipotônica”, “isotônica”, e sinônimos ou termos relacionados. SíNTESE DOS DADOS: A solução de manutenção e regime de fluido ideais permanecem um ponto de controvérsia em pediatria. As recomendações tradicionais para fluidos de manutenção são cada vez mais criticadas por não se aplicarem consistentemente à doença aguda, onde o gasto de energia e a necessidade de eletrólitos se desviam significantemente das estimativas originais. Apresentamos uma estrutura fisiologicamente fundamentada para a prescrição de fluidos de manutenção, com o objetivo de manter a tonicidade em equilíbrio, e administrar o volume mínimo de fluidos de manutenção necessário para manter a hemodinâmica. Discutimos também as indicações para soluções isotônicas e hipotônicas. CONCLUSÕES: As prescrições de fluidos de manutenção devem ser individualizadas. Não existe uma solução endovenosa única e ideal para todas as crianças durante todas as fases da doença, mas há evidências suficientes para sugerir que a escolha empírica mais segura é uma solução isotônica. As soluções hipotônicas devem ser consideradas apenas se o objetivo é alcançar um equilíbrio positivo de água livre. As crianças em estado grave podem necessitar de uma redução de até 40-50 por cento dos volumes de manutenção atualmente recomendados. Todos os pacientes que receberem fluidos endovenosos devem ser monitorados bem de perto, com pesagem diária, equilíbrio dos fluidos, controle dos parâmetros bioquímicos e clínicos, a fim de melhor orientar esta terapia.

OBJECTIVE: To examine electrolyte-free water requirements that should be considered when administering maintenance fluids in a critically ill child. We examine some of the difficulties in estimating these requirements, and discuss the controversies with respect to the traditional recommendations. SOURCES: MEDLINE (1966-2007), Embase (1980-2007), and the Cochrane Library, using the terms: “fluid therapy”, “hypotonic”, “isotonic solution”, and synonyms or related terms. SUMMARY OF THE FINDINGS: The ideal maintenance solution and fluid regimen remains a topic of heated debate in pediatrics. The traditional recommendations for maintenance fluids are increasingly criticized as they do not consistently apply in acute illness, where energy expenditure and electrolyte requirements deviate significantly from the original estimates. A physiologically based framework for prescribing maintenance fluids is presented, with the objective of maintaining tonicity balance, and infusing the minimum volume of maintenance fluid required to maintain hemodynamics. Indications for isotonic and hypotonic solutions are discussed. CONCLUSIONS: Maintenance fluid prescriptions should be individualized. No single intravenous solution is ideal for every child during all phases of illness, but there is evidence to suggest that the safest empirical choice is an isotonic solution. Hypotonic solutions should only be considered if the goal is to achieve a positive free-water balance. Critically ill children may require a reduction by as much as 40-50 percent of the currently recommended maintenance volumes. All patients receiving intravenous fluids should be monitored closely with daily weights, fluid balances, biochemical and clinical parameters in order to best guide this therapy.