Diabetic Ketoacidosis (DKA) Calculator
Enter key lab values to confirm American Diabetes Association (ADA) diagnostic criteria for diabetic ketoacidosis, grade severity, compute the anion gap with albumin correction, and estimate in-hospital mortality risk using the DKA Mortality Prediction Model (DKA MPM) score. All four ADA criteria must be present for a DKA diagnosis. Results update as you type.
What is diabetic ketoacidosis (DKA)?
Diabetic ketoacidosis is a life-threatening acute complication of diabetes mellitus caused by a severe shortage of effective insulin. Without enough insulin, cells cannot use glucose for energy. Instead, the liver breaks down fat into ketone bodies (acetoacetate, beta-hydroxybutyrate, and acetone), which are acidic. The accumulation of these ketones lowers blood pH, producing a metabolic acidosis. DKA occurs most often in type 1 diabetes but can also complicate type 2 diabetes during illness, injury, or extreme physiological stress. Classic precipitating factors include missed or inadequate insulin doses, infection, new-onset type 1 diabetes, myocardial infarction, and certain medications (such as SGLT-2 inhibitors at low blood glucose levels, a presentation sometimes called euglycemic DKA).
ADA diagnostic criteria and how this calculator applies them
The American Diabetes Association requires all four of the following for a DKA diagnosis: (1) blood glucose above 250 mg/dL (13.9 mmol/L); (2) positive serum or urine ketones; (3) arterial pH below 7.30; and (4) serum bicarbonate below 18 mEq/L. This calculator checks each criterion and reports how many of the four are present. Severity is then graded from mild to severe using arterial pH, bicarbonate level, and mental status. Mild DKA is defined by pH 7.24-7.30 and HCO3 15-18 mEq/L with the patient alert. Moderate DKA spans pH 7.00-7.24 or HCO3 10-15 mEq/L, with the patient possibly drowsy. Severe DKA applies when pH drops below 7.00, HCO3 falls under 10 mEq/L, or the patient is in stupor or coma. Note that in euglycemic DKA the glucose criterion may not be met, so clinical judgment remains essential.
Understanding the anion gap and its albumin correction
The anion gap (AG) is calculated as serum sodium minus the sum of chloride and bicarbonate: AG = Na - (Cl + HCO3). A normal result is up to 12 mEq/L using a three-electrolyte formula. In DKA, organic acids (ketone bodies) are unmeasured anions, so the gap widens, typically to 16 mEq/L or beyond. Because albumin is the main unmeasured anion in normal plasma, hypoalbuminemia can mask a true anion gap acidosis by reducing the expected baseline gap. The albumin-corrected anion gap adds 2.5 mEq/L for every 1 g/dL that albumin falls below 4 g/dL: corrected AG = AG + 2.5 x (4 - albumin). Patients who are critically ill often have low albumin, so interpreting the raw AG without this correction can cause a high-gap acidosis to be missed. Effective osmolality (2 x Na + glucose/18) is also computed because very high osmolality (>320 mOsm/kg) alongside less severe acidosis suggests a mixed DKA/HHS picture.
DKA Mortality Prediction Model (DKA MPM) score
The DKA MPM score, published by Kitabchi and colleagues in 2009, estimates in-hospital mortality by assigning points to six risk factors measured at presentation and over the first 24 hours: severe comorbidity at presentation (+6), pH <7.0 at presentation (+4), more than 50 units of regular insulin required in the first 12 hours (+4), blood glucose remaining above 300 mg/dL at 12 hours (+4), depressed mental state persisting to 24 hours (+4), and fever at 24 hours (+3). A score of 0 carries near-zero expected mortality; scores above 10 correspond to markedly increased risk. The authors themselves caution that the model is not externally validated and that the APACHE II score may outperform it as a general mortality predictor. Use the DKA MPM as one piece of clinical context, not as a standalone disposition tool.
Key management priorities in DKA
Regardless of severity, the three pillars of DKA treatment are fluids, insulin, and electrolyte replacement, pursued simultaneously. Isotonic saline (0.9% NaCl) is started at 1-1.5 litres in the first hour to restore intravascular volume, then adjusted for the patient's haemodynamic state. Insulin infusion should not be started until serum potassium is confirmed to be at or above 3.5 mEq/L, because insulin drives potassium into cells and can precipitate dangerous hypokalaemia. Once glucose drops to 200-250 mg/dL, the infusion switches to dextrose-containing fluid to avoid hypoglycaemia while continuing to clear ketones. Bicarbonate administration remains controversial and is generally reserved for pH below 6.9 with haemodynamic instability. The anion gap, rather than glucose alone, is the best guide to resolution: the gap should close to 12 mEq/L or below before transitioning from intravenous to subcutaneous insulin.
ADA DKA Severity Classification
| Parameter | Mild DKA | Moderate DKA | Severe DKA |
|---|---|---|---|
| Arterial pH | 7.24-7.30 | 7.00-7.24 | <7.00 |
| Serum HCO3 (mEq/L) | 15-18 | 10-<15 | <10 |
| Anion gap (mEq/L) | >12 | >12 | >12 |
| Mental status | Alert | Alert / Drowsy | Stupor or Coma |
| Typical ICU need | Rarely | Sometimes | Usually |
American Diabetes Association severity bands. All four diagnostic criteria (glucose >250, pH <7.3, HCO3 <18, ketones positive) must be present to confirm DKA. Severity is determined by the worst single parameter.
Frequently asked questions
What are the four ADA criteria for diagnosing DKA?
The American Diabetes Association requires all four of the following: blood glucose above 250 mg/dL (13.9 mmol/L), positive serum or urine ketones, arterial pH below 7.30, and serum bicarbonate below 18 mEq/L. All four must be present to confirm DKA. If fewer than four criteria are met, consider alternative diagnoses such as hyperglycemic hyperosmolar state (HHS), alcoholic ketoacidosis, starvation ketosis, or lactic acidosis.
How is the anion gap calculated, and why does it matter in DKA?
The anion gap equals serum sodium minus the sum of chloride and bicarbonate: Na - (Cl + HCO3). A result above 12 mEq/L is elevated. In DKA, ketone bodies are acids that consume bicarbonate and appear as unmeasured anions, widening the gap to 16 mEq/L or more. Monitoring the anion gap during treatment tells you whether ketoacidosis is truly resolving, regardless of what the glucose is doing, so clinicians use gap closure to below 12 mEq/L as a key criterion before switching from IV to subcutaneous insulin.
What is euglycemic DKA and would this calculator flag it?
Euglycemic DKA is a variant where blood glucose is below 250 mg/dL despite significant ketoacidosis. It is increasingly reported in patients using SGLT-2 inhibitors (empagliflozin, dapagliflozin, canagliflozin), in pregnant women, and in patients with reduced oral intake. Because the glucose criterion is not met, this calculator would show only 3/4 ADA criteria and would not confirm DKA, correctly reflecting the limitation of the standard thresholds. If euglycemic DKA is clinically suspected, focus on the anion gap, serum beta-hydroxybutyrate, and clinical context rather than relying on glucose alone.
Why should potassium be checked before starting insulin in DKA?
Acidosis causes potassium to shift out of cells into the plasma, so total body potassium is actually depleted despite the serum level appearing normal or even high. When insulin is given, it drives potassium back into cells rapidly, unmasking severe hypokalaemia. Hypokalaemia can trigger life-threatening cardiac arrhythmias. The standard recommendation is to delay insulin until serum potassium is at or above 3.5 mEq/L, and to add potassium to the IV fluids until it is above 5.0 mEq/L.
What is the difference between DKA and hyperglycemic hyperosmolar state (HHS)?
Both are acute hyperglycemic emergencies, but they differ in ketosis, acidosis, and osmolality. DKA features significant ketosis and metabolic acidosis (pH <7.30) at a glucose usually in the 250-600 mg/dL range and an effective osmolality typically below 320 mOsm/kg. HHS involves much higher glucose (often above 600 mg/dL) and osmolality (above 320 mOsm/kg) with minimal or no ketosis and pH usually above 7.30. HHS occurs predominantly in type 2 diabetes in older adults. Mixed DKA/HHS presentations do exist, particularly in children. Effective osmolality computed by this calculator can help identify the overlap.
When does the anion gap close and how is DKA resolution defined?
DKA is considered resolved when three criteria are all met together: blood glucose below 200 mg/dL, anion gap at or below 12 mEq/L, and serum bicarbonate at or above 15 mEq/L. Of these, gap closure is the most reliable marker. Glucose often normalises well before acidosis clears, and premature insulin discontinuation based on glucose alone is a common cause of recurrence. The calculator monitors all three relevant lab values to help track resolution.
What does the DKA MPM score tell me?
The DKA Mortality Prediction Model score (Kitabchi 2009) estimates in-hospital mortality using six risk factors gathered at presentation and during the first 24 hours: severe comorbidity, initial pH below 7.0, high insulin requirement at 12 hours, persistent hyperglycemia at 12 hours, depressed consciousness at 24 hours, and fever at 24 hours. A score of 0 corresponds to near-zero mortality. Scores above 10-15 suggest substantially elevated risk. The model is not externally validated, and the authors recommend pairing it with broader clinical assessment.