Anion Gap Delta Delta Gradient Multicalc

 

Input
 

Na		mEq/L
Cl		mEq/L
HCO3		mEq/L
Baseline Gap		mEq/L

 

Results
 

Anion Gap		mEq/L
Delta Gap		mEq/L
Delta HCO3		mEq/L
Delta Delta Gradient		mEq/L
Decimal Precision   0 1 2 3

 

 

 
A simple high anion gap metabolic acidosis produces a Delta Delta Gradient around 0.
 
A Delta Delta Gradient significantly greater than 0 usually indicates either:

• A mixed high anion gap metabolic acidosis plus a primary metabolic alkalosis.
• A mixed high anion gap metabolic acidosis plus a chronic respiratory acidosis.
• A non-acidotic high anion gap state (such as with excess penicillin administration.)

 
A Delta Delta Gradient significantly less than 0 may result from:

• A mixed high anion gap metabolic acidosis plus a normal anion gap metabolic acidosis.
• A mixture of high anion gap metabolic acidosis plus chronic respiratory alkalosis plus hyperchloremia acidosis.
• A high anion gap acidosis with a prexisting low anion gap state (such as hypoalbuminemia, para-proteinemia, etc ...)

 

 
Equations used
 

AnionGap = Na - (Cl + HCO3)

DeltaGap = AnionGap - BaselineGap

DeltaHCO3 = 25 - HCO3

DeltaDeltaGradient = DeltaGap - DeltaHCO3

 

 

References

1. Wrenn K. The delta (delta) gap: an approach to mixed acid-base disorders. Ann Emerg Med. 1990 Nov;19(11):1310-3. PubMed ID: 2240729
2. Breyer JA. Acid base course material. 6th National Critical Care Medicine Review Course.