Tutorial to help answer this question

Your patient presents with the following blood gases. When questioned about his diet, he admits to binging on citrus fruits in the past few weeks, and his favorite drinks are grapefruit and tomato juice.

What condition does this patient appear to have?

Compensated metabolic acidosis would manifest in deviation from normal blood values as highlighted in the table below. Note that the primary defect is indicated by a decrease in bicarbonate ion concentration. (For an explanation as to how this indicates the primary defect, see tutorial for Problem 5.) The compensation is indicated by a decrease in pCO₂. This is due to increased CO₂ expulsion by the lung, which is the most effective compensation for this metabolic problem. It is worth remembering that any non-respiratory (i.e."metabolic") pH disorder is best compensated in the lung.

	respiratory					metabolic
	acidosis		alkalosis			acidosis		alkalosis
	U	C	U	C		U	C	U	C
pH
HCO3-:CO2 ratio
[HCO3-]
pCO2
total CO2

= increased = decreased = no major change

U = uncompensated C = compensated = Red arrows indicate the primary defect. = Green arrows indicate compensation mechanisms.