Acid-base balance regulating drugs

Classification
Acid-base balance regulating drugs is divided into two categories:
①medicine for acidosis such as sodium bicarbonate, sodium lactate, etc. which are commonly used;
②medicine for alkalosis such as ammonium chloride which is commonly used.

Mechanism
According to the original causes, acid-base disturbance can be divided into four basic types including metabolic acidosis and alkalosis, whose original causes are metabolic, and respiratory acidosis and alkalosis, whose original causes are respiratory.
Metabolic acidosis refers to the relatively excessive amount of H + in extracellular fluid, which may be caused by an excessive production of H + or a decrease of HCO3-. To treat metabolic acidosis, intravenous administration is mainly applied to increases the HCO3- concentration and neutralize hydrogen ions in the plasma，thereby to regulate acidosis. Metabolic alkalosis refers to the relatively excessive amount of HCO3- in extracellular fluid, which may be caused by an excessive production of HCO3- or a decrease of H +. To treat metabolic alkalosis, intravenous administration is mainly applied to decrease the HCO3- concentration in plasma in order to regulate alkalosis. Respiratory acidosis refers to the increased H2CO3 concentration and the decreased pH in blood caused by the increased alveolar PaCO2 due to a weakened alveolar ventilation. Basic drugs are not usually used in treatment of respiratory acidosis, unless the pH drops rapidly. Instead, respiratory acidosis is mainly treated by improving the patient's alveolar ventilation. Respiratory alkalosis refers to the decreased CO2 concentration and the increased pH in blood caused by the increased CO2 excretion due to excessive alveolar ventilation. Treatment of respiratory alkalosis is mainly through an active treatment of the protopathy in order to control hyperventilation.

Clinical application
Acid-base balance regulating drugs is mainly used to regulate acid-base balance. Treatment of acidosis and alkalosis includes the basic etiological treatment and the regulation of acidosis and alkalosis. Correction of acid-base balance disorders should not be hypercorrection and simultaneous observation over therapeutic response should be implemented for the close observation is highly demanded throughout the treatment.

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