Anion Gap Calculator
Calculate anion gap with sodium, potassium, chloride, and bicarbonate values
Anion Gap Formulas
Standard Anion Gap = Na+ - (Cl- + HCO3-)
Anion Gap with K+ = (Na+ + K+) - (Cl- + HCO3-)
These formulas help identify acid-base disorders in clinical practice.
Why Anion Gap Matters:
- Helps diagnose metabolic acidosis
- Differentiates between types of acid-base disorders
- Useful in emergency medicine and critical care
- Important for evaluating kidney function
Key Insights:
Normal Anion Gap
Typically 8-12 mEq/L (with K+) or 3-11 mEq/L (without K+)
High Anion Gap
Suggests metabolic acidosis from unmeasured anions
Low Anion Gap
May indicate hypoalbuminemia or laboratory error
How Our Anion Gap Calculator Works
Enter Lab Values
Input your patient's sodium, potassium, chloride, and bicarbonate values from lab results.
Calculate Anion Gap
Our calculator computes both standard anion gap and anion gap with potassium automatically.
Get Clinical Interpretation
Receive immediate interpretation of results with clinical significance for diagnosis.
Understanding Anion Gap: A Key Diagnostic Tool
The anion gap calculator is an essential clinical tool that helps healthcare providers evaluate acid-base disorders. By measuring the difference between measured cations and anions in serum, the anion gap provides valuable diagnostic information about metabolic acidosis and other conditions.
What is Anion Gap?
Anion gap is a calculated value that represents the difference between positively charged ions (cations) and negatively charged ions (anions) in the blood. The anion gap formula helps identify the presence of unmeasured anions, which is particularly useful in diagnosing metabolic acidosis.
How to Calculate Anion Gap
There are two primary methods for calculating anion gap:
- Standard Anion Gap (without potassium): Na+ - (Cl- + HCO3-)
- Anion Gap with Potassium: (Na+ + K+) - (Cl- + HCO3-)
Our anion gap calculator with CO2 (bicarbonate) makes these calculations quick and accurate, eliminating manual calculation errors.
Clinical Significance of Anion Gap
Anion gap results can indicate various medical conditions:
High Anion Gap Metabolic Acidosis
A high anion gap (typically >12 mEq/L) suggests metabolic acidosis caused by:
- Diabetic ketoacidosis (DKA)
- Lactic acidosis
- Renal failure
- Toxic ingestions (methanol, ethylene glycol)
Normal Anion Gap Metabolic Acidosis
A normal anion gap acidosis (hyperchloremic acidosis) may indicate:
- Diarrhea
- Renal tubular acidosis
- Certain medication effects
Low Anion Gap
A low anion gap (<3 mEq/L) may suggest:
- Hypoalbuminemia
- Multiple myeloma
- Laboratory error
Disclaimer
This anion gap calculator is for informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.
Recommended Medical Resources
- PubMed - National Library of Medicine research database
- UpToDate - Evidence-based clinical decision support
- Merck Manuals - Professional medical reference
- Medscape - Medical news & expert perspectives
- Mayo Clinic - Trusted health information
- NEJM - New England Journal of Medicine
- AAFP - American Academy of Family Physicians
- National Kidney Foundation - Kidney health resources
- American Diabetes Association - Diabetes information
- CDC - Centers for Disease Control and Prevention