Respiratory&Metabolic Acidosis/Alkalosis

Hi,

I'm learning about ABG's and I don't understand how someone can have respiratory AND metabolic acidosis or alkalosis. It doesn't make sense because wouldn't the body want to increase the base or acid to get the pH in normal range.

Any explanation or websites would be greater appreciated! Thanks!
Respiratory vs. metabolic acidosis/alkalosis references to two different mechanisms of acid/base balance. Someone can experience respiratory acidosis due to inadequate alveolar ventilation and CO2 retention (respiratory acidosis) AND someone can experience metabolic acidosis because the kidneys are not removing enough acid from the body due to organ failure or malfunction OR perhaps because the body is steadily losing bicarbonate because of prolonged diarrhea or not producing a sufficient amount (metabolic acidosis). Two different reasons, two different systems, producing the same result.