From the Guidelines
Metabolic alkalosis is primarily caused by excessive loss of hydrogen ions or gain of bicarbonate in the body, with the main causes including vomiting, diuretic use, excessive alkali administration, severe potassium depletion, and certain endocrine disorders like hyperaldosteronism or Cushing's syndrome, as well as rare tubulopathies such as Bartter syndrome, which is characterized by hypokalemic metabolic alkalosis, as noted in the 2021 study published in Kidney International 1.
Causes of Metabolic Alkalosis
The causes of metabolic alkalosis can be categorized into several main groups:
- Excessive loss of hydrogen ions, such as through vomiting or nasogastric suction, which removes acidic gastric contents
- Gain of bicarbonate, such as through excessive alkali administration, including sodium bicarbonate or antacids containing calcium carbonate
- Severe potassium depletion, which can occur due to various reasons, including diuretic use or certain endocrine disorders
- Certain endocrine disorders, such as hyperaldosteronism or Cushing's syndrome, which can lead to mineralocorticoid excess and impaired kidney function
- Rare tubulopathies, such as Bartter syndrome, which is characterized by hypokalemic metabolic alkalosis, as noted in the 2021 study published in Kidney International 1
Rare Tubulopathies
Rare tubulopathies, such as Bartter syndrome, can also cause metabolic alkalosis, as noted in the 2021 study published in Kidney International 1. Bartter syndrome is characterized by hypokalemic metabolic alkalosis, and its diagnosis and management are discussed in the 2021 study published in Kidney International 1.
Diagnosis and Management
The diagnosis and management of metabolic alkalosis should address the underlying cause, replace fluid and electrolyte losses, and correct potassium deficiency, as noted in the example answer. In severe cases, acetazolamide may be used to increase bicarbonate excretion, or dilute hydrochloric acid may be administered in critical situations under careful monitoring. The 2018 study published in the European Heart Journal 1 discusses the management of hyperkalaemia, which can be related to metabolic alkalosis, and notes that treatment should be initiated as early as possible to prevent rebound hyperkalaemia.
From the FDA Drug Label
Excess administration of Multiple Electrolytes Injection, Type 1, USP can result in metabolic alkalosis. metabolic alkalosis with or without hypokalemia and decreased ionized serum calcium and magnesium concentrations
The cause of metabolic alkalosis mentioned in the drug label is excess administration of Multiple Electrolytes Injection, Type 1, USP 2 and 2.
From the Research
Causes of Metabolic Alkalosis
The causes of metabolic alkalosis can be understood by examining the pathogenesis of the disorder, which involves either a loss of fixed acid or a net accumulation of bicarbonate within the extracellular fluid 3. The key factors that contribute to metabolic alkalosis include:
- Loss of acid via the gastrointestinal tract or the kidney
- Net accumulation of bicarbonate due to oral or parenteral alkali intake
- Volume contraction, which impairs the kidney's ability to eliminate excess bicarbonate
- Low glomerular filtration rate, potassium deficiency, hypochloremia, aldosterone excess, and elevated arterial carbon dioxide, all of which interfere with the kidney's mechanisms for eliminating excess bicarbonate 3
- Precipitating events such as diuretic therapy and prolonged nasogastric suctioning, which can lead to primary metabolic alkalosis 4
- Perpetuating mechanisms, including volume depletion, which can aggravate the condition 4
- Factors that generate the alkalosis, such as the source of fluid loss and composition, and less commonly, alkali administration 5
- Factors that maintain the abnormality, including extracellular fluid volume status and hormonal systems 5
Clinical States Associated with Metabolic Alkalosis
Metabolic alkalosis is associated with several major clinical states, including:
- Vomiting
- Aldosterone or cortisol excess
- Licorice ingestion
- Chloruretic diuretics
- Excess calcium alkali ingestion
- Genetic diseases such as Bartter syndrome, Gitelman syndrome, and cystic fibrosis 3