Here is what I think you are supposed to do for acid-base disorders, PLEASE correct me if I am wrong. 1. Look at pH, HCO3, and PC02 to figure out the primary acid-base disorder (e.g. metabolic acidosis). If met acidosis, calculate anion gap to see if high or normal anion gap. 2. Use Winter's formula and the other chronic/acute resp alk/acidosis relationships to figure out if the compensation is appropriate OR if there a 2nd acid-base disorder present 3. If met acidosis, calculate delta anion gap. If >31, there is a metabolic alkalosis (now we're up to a 3rd disorder). If <21, there is a nonanon gap metabolic acidosis. If between 21 and 31, there is no third acid-base disorder. PLEASE correct this if I am wrong... I put this together from 3 different sources!! Thanks.