Which lab value is most closely associated with metabolic alkalosis?

Metabolic alkalosis is characterized by an increase in blood pH, which often occurs due to factors such as excessive loss of hydrogen ions, bicarbonate overload, or decreased chloride levels. The lab value most closely associated with metabolic alkalosis is low chloride levels.

In cases of metabolic alkalosis, especially when it results from conditions like vomiting or diuretic use, there tends to be a corresponding decrease in chloride levels. This is because the loss of acidic gastric secretions (which contain hydrogen and chloride ions) or the effects of certain diuretics can lead to a relative deficit of chloride, contributing to the alkalosis.

High potassium is generally more related to conditions like metabolic acidosis or certain renal issues, while high chloride levels are often not associated with metabolic alkalosis but can be seen in other acid-base disturbances. An increased BUN can indicate dehydration or renal issues but is not a defining marker of metabolic alkalosis.