Sistemática para el manejo del equilibrio ácido-base en pacientes graves / Systemization for the management of acid-base balance in seriously ill patients

Introducción: Las alteraciones del equilibrio ácido-base pueden ser de carácter primario. En la mayoría de los casos dependen de la complicación de una enfermedad preexistente. La frecuencia de estos trastornos es elevada, especialmente, en enfermos hospitalizados en las unidades de atención al paciente grave. Su aparición conlleva implicaciones pronósticas significativas. Objetivo: Sistematizar sobre el estado actual del manejo del equilibrio ácido-base. Método: Se realizó una revisión bibliográfica en la que se utilizaron las herramientas del método científico. Se examinó toda la bibliografía disponible publicada en los últimos cinco años y así, elaborar una síntesis crítica, acorde al criterio y las competencias de los autores sobre la temática. Resultados: Se expone la importancia de la evaluación clínica, que unida a los niveles de PCO2, y de exceso o déficit de bases en una gasometría arterial, permiten identificar el trastorno ácido base existente. Igualmente, se destaca que el CO2 tiene una función clave en el control de la ventilación, así como las modificaciones que produce al flujo sanguíneo cerebral, el pH y el tono adrenérgico. Otro aspecto importante fue la reciente práctica clínica de la "hipercapnia permisiva" para reducir el metabolismo tisular y de esta manera, mejorar la función del surfactante e impedir la nitración de las proteínas. Conclusiones: El manejo de los desequilibrios ácido-base debe ser del dominio de todos los profesionales vinculados a la asistencia médica, pues el retraso de su diagnóstico puede empeorar la evolución y el pronóstico de los pacientes graves(AU)

Introduction: Acid-base balance alterations can be of a primary nature. In most cases, they depend on the complication of a pre-existing disease. The frequency of these disorders is high, especially in patients hospitalized in critical care units. Its appearance carries significant prognostic implications. Objective: To systematize the current state of acid-base balance management. Method: A bibliographic review was carried out, for which the tools of the scientific method were used. All the available bibliography, published in the last five years, was examined; thus, a critical synthesis was prepared, according to the criteria and competences of the authors regarding the subject. Results: The importance of the clinical evaluation is exposed, which, together with PCO2 levels as well as excess or deficit of bases in an arterial blood gas, allow to identify the existing acid-base disorder. Likewise, it is highlighted that CO2 has a key function in ventilation control, together with the modifications it produces on cerebral blood flow, pH and adrenergic tone. Another important aspect was the recent clinical practice of "permissive hypercapnia" to reduce tissue metabolism and thus improve surfactant function and prevent protein nitration. Conclusions: The management of acid-base imbalances should be mastered by all professionals associated to medical care, since any delay in its diagnosis can worsen the evolution and prognosis of seriously ill patients(AU)

Caracterização dos distúrbios da regulação ácido-base: uma abordagem didática e intuitiva / Characterization of acid-base regulation disorders: a didactic and intuitive approach

Em humanos, o pH sanguíneo é mantido em uma faixa estreita, entre 7,35 e 7,45. Diferentes mecanismos bioquímicos, de forma harmônica, atuam para a manutenção do pH fisiológico. Múltiplos processos patológicos podem promover alterações no pH e nos gases sanguíneos, caracterizando acidose (pH <7,35) ou alcalose (pH >7,45). A ruptura da homeostasia do pH é identificada pela medição do pH, pressão parcial de dióxido de carbono (pCO2), concentração do bicarbonato (HCO3-) e, adicionalmente, com a pressão de oxigênio (pO2) em sangue arterial, processo descrito como gasometria arterial. Este artigo revisa os principais elementos associados a compreensão das alterações e tem como objetivo central apresentar uma abordagem didática e intuitiva para a caracterização destes distúrbios; e também comenta sobre ferramentais digitais destinadas a interpretações das alterações da gasometria arterial que também são abordados, como programas para computadores em ambiente web e aplicativos para telefonia móvel.

In humans, blood pH is kept in a narrow range, between 7.35 to 7.45. Different biochemical mechanisms, in a harmonic way, act to maintain the physiological pH. Multiple pathological processes can promote changes in pH and blood gases, characterizing acidosis (pH <7.35) or alkalosis (pH> 7.45). The rupture of pH homeostasis is identified by measuring pH, partial pressure of carbon dioxide (pCO2), bicarbonate concentration (HCO3 - and, in addition, with the pressure of oxygen (pO2) in arterial blood, a process described as gasometry arterial. This article reviews the main elements associated with the understanding of acid-base changes and aims to present a didactic and intuitive approach to the characterization of these disorders; and also comments on digital tools for the interpretation of alterations in arterial blood gases are also covered, such as programs for computers in a web environment and applications for mobile phone.

Identifying hydric, electrolytic and acid-base imbalances through traditional and quantitative approaches in dogs with hemorrhagic gastroenteritis / Identificação de desequilíbrios hídricos, eletrolíticos e ácido-base pelas abordagens tradicional e quantitativa em cães com gastroenterite hemorrágica

Vomiting and diarrhea are two important clinical signs that can cause significant electrolytic and acid-base imbalances. The purposes of this study were to characterize hydric, electrolytic and acid-base disorders presented by puppies with hemorrhagic gastroenteritis and to compare the traditional and quantitative approaches to acid-base status interpretation. Sixty-one animals with a history of vomiting and/or diarrhea were used in this study and the following tests were performed: complete blood count, total plasma protein concentration and hemogasometry. Mean, standard deviation and Kappa values were calculated. The imbalances characterized by both approaches were: 42 (69%) animals without imbalance, 17 (28%) with metabolic alkalosis and 2 (3%) with metabolic acidosis by the traditional approach and 17 (28%) dogs without imbalance, 26 (43%) with metabolic alkalosis and 18 (29%) with metabolic acidosis by the quantitative approach. The agreement calculated between two approaches coincide in 28 cases, with a moderate Kappa value equivalent to 0.459. The most found imbalances were metabolic alkalosis, hypokalemia, and mild dehydration. Most of acid-base disturbances were not identified by the traditional approach, whereas by the quantitative approach, they were easily determined. Thus quantitative approach proved to be superior in identification of possible acid-base imbalances.(AU)

Vômito e diarreia são dois sinais clínicos importantes, que podem causar desequilíbrios eletrolíticos e ácido-base importantes. Os objetivos deste trabalho foram caracterizar os desequilíbrios hídrico, eletrolítico e ácido-base apresentados por filhotes de cães com gastroenterite hemorrágica e comparar as abordagens de interpretação do equilíbrio ácido-base tradicional e quantitativa. Sessenta e um animais com histórico de vômito e/ou diarreia foram utilizados neste estudo, e os seguintes testes foram realizados: hemograma, concentração de proteína total plasmática e hemogasometria. Média, desvio-padrão e valor de Kappa foram calculados. Os desequilíbrios caracterizados pelas duas abordagens foram: 42 (69%) animais sem desequilíbrio, 17 (28%) com alcalose metabólica e dois (3%) com acidose metabólica, pela abordagem tradicional, e 17 (28%) cães sem desequilíbrio, 26 (43%) com alcalose metabólica e 18 (29%) com acidose metabólica, pela abordagem quantitativa. A concordância calculada entre as duas abordagens coincidiu em 28 casos, com um valor de Kappa moderado, equivalente a 0,459. Os desequilíbrios mais encontrados foram alcalose metabólica, hipocalemia e desidratação leve. A maioria dos distúrbios não foram identificados pela abordagem tradicional, enquanto, pela abordagem quantitativa, foram facilmente determinados. Portanto, a abordagem quantitativa provou-se superior na identificação de possíveis desequilíbrios ácido-base.(AU)

Acid based disorders in intensive care unit: a hospital-based study

Background: Acid base disorders are common in the ICU patients and pose a great burden in the management of the underlying condition.Methods: Identifying the type of acid-base disorders in ICU patients using arterial blood gas analysis This was a retrospective case-controlled comparative study. 46 patients in intensive care unit of a reputed institution and comparing the type of acid-base disorder amongst infectious (10) and non-infectious (36) diseases.Results: Of the study population, 70% had mixed acid base disorders and 30% had simple type of acid base disorders. It was found that sepsis is associated with mixed type of acid-base disorders with most common being metabolic acidosis with respiratory alkalosis. Non-infectious diseases were mostly associated with metabolic alkalosis with respiratory acidosis. Analysis of individual acid base disorders revealed metabolic acidosis as the most common disturbance.Conclusions: These results projected the probability of acid bases disorders in various conditions and help in the efficient management. Mixed acid base disorders are the most common disturbances in the intensive care setup which is metabolic acidosis with respiratory alkalosis in infectious diseases and metabolic acidosis is the most common simple type of acid base disorder.

Electrolyte and acid-base disturbances in the critically ill patients: A retrospective case control study

Background: Electrolyte and acid-base disturbances are common in critically ill patients. Early appreciation and appropriate interventions to maintain this internal milieu are lifesaving and cost effective for the patients. Objective of the study: To analyze the effects of electrolyte and acid-base disturbances on hospital mortality in critically ill patients. Materials and methods: A retrospective case control study was done on 100 patients in the intensive care unit of our hospital for six months. Results: The incidences of electrolyte and acid-base disturbances were higher in non-survivors than survivors. The serum potassium value had both clinical (4.318 in the survivors vs. 4.815 in the nonsurvivors) and statistical significance (p=0.0298) between the survivor and non-survivor group. Arterial blood HCO3 (0.0304), CO2 (P=0.0396) and pH (P=0.015) at admission were statistically different between the two groups. The incidence rates of hyperkalemia (65%), respiratory acidosis (62.5%) and mixed metabolic acidosis and respiratory acidosis (65%) were higher in the non-survivor group. Conclusion: Electrolyte and acid-base disturbances hyperkalemia, respiratory acidosis and mixed respiratory with metabolic acidosis are highly associated with hospital mortality

Acid-base Disorders in Status Epilepticus / 대한소아신경학회지

PURPOSE: Convulsive status epilepticus induces disturbance in acid-base homeostasis. It is known that metabolic acidosis is common after status epilepticus. A recent, discovery indicates respiratory acidosis is common after status epilepticus. This study is to analyze the acid-base disturbances in patients with status epilepticus. METHODS: Retrospectively, we reviewed twenty-five patients with status epilepticus, who were admitted to the pediatric department of Chosun University Hospital between January 1995 and August 2000. We have analyzed the clinical correlation among the acid-base disturbance, the incidence of pulmonary infiltration, and the type and duration of convulsions. RESULTS: Acid-base disorders in the status epilepticus were revealed in 17(68%) of 25 patients. Respiratory acidosis with or without metabolic acidosis was most common(N= 13; 52%). There was no significant correlation between the pulmonary infiltration(N=8; 32%) and the acid-base disorders(P>0.05). The most common seizure type in status epilepticus was generalized tonic clonic(72%). In that type, the most common acid-base disorder was respiratory acidosis(11/18). The mean serum pH was significantly decreased with duration of seizures(P<0.05). CONCLUSION: This study finds that respiratory acidosis with or without metabolic acidosis was most common in status epilepticus. There was no significant correlation between pulmonary infiltration and acid-base disorders. Respiratory acidosis was most common in generalized tonic clonic seizure.

AN EVALUATION OF THE ACID-BASE DISORDERS AND DIAGNOSTIC CRITERION OF RESPIRATORY FAILURE IN CHRONIC COR PULMONALE IN XINING / 解放军医学杂志

The blood gases and acid-base disorders were analysed in 276 cases with chronic cor pulmonale at 2260m above sea level (Xining). The results demonstrated that: (1) the incidence of acid-base disorders, respiratory acidosis and the ratio of compensatory to decompensatory respiratory acidosis were low, the rate of respiratory alkolosis was high, if they were evaluated according to the formula used on plains. If normal values determined in Xining were used, the various incidences were about the same as observed on plains. (2) In diagnosing respiratory failure with blood gas analysis if the criteria commonly employed on plains was applied, the incidence of type J respiratory failure was higher, and that of type I was lower. If PaO25.33kPa were used as the criteria for respiratory failue, the incidence of type I respiratory failure became lower with type Ⅱ higher. The characteristics of acid-base disorders and diagnostic criteria of respiratory failure in patients with cor pulmonale were discussed.