Compensation by respiratory means is very fast, occuring within seconds or minutes. This compensation occurs via the body's control of respiratory rate through the brain respiratory center. Thus respiratory compensation for metabolic abnormalities is seen almost immediately. Metabolic compensation, on the other hand, is slow. It occurs through elimination of acid or alkali by the kidney.
Hours go by before significant compensation is seen.
Metabolic compensation will occur for chronic respiratory disturbance, but also, metabolic correction through the kidney will be seen for metabolic disturbances. Identifying the source of acidosis and presence of compensation assumes that the same process has been going on all along. For example, Phil Smith has a heart attack and goes into V-fib. He develops both respiratory and metabolic acidosis. Then he gets defibrillated and wakes up.