Delta gap
<p>delta ratio   = ∆AG/∆HCO3
 
                          =      (AG – 12)   
                               (24 - [HCO3-])
 
 
What is the delta gap?
• Use this when you have a patient with anion-gap acidosis to see if there is a concomitant non-gap
metabolic acidosis or metabolic alkalosis.
• First, calculate the delta gap = patient’s anion gap – normal anion gap = patient’s anion gap – 12
• Then, add the delta gap to the patient’s bicarbonate.  If it is < 24, there is a concomitant non-gap metabolic acidosis; if it is > 30, there is a concomitant metabolic alkalosis.</p>