Endocrine · Topic 1 of 13
Diabetic Ketoacidosis (DKA)
Endocrine · hyperglycemic crisis
Diabetic Ketoacidosis (DKA)
Glucose ≥ 200 or known diabetes, ketones ≥ 3.0 and acidosis: fluids first, potassium above 3.5, then an insulin drip until ketoacidosis clears.
Key numbers
Glucose, ketones and acidosis requiredpH < 7.3 / HCO₃⁻ < 18
Isotonic fluids 500–1000 mL/h first500–1000 mL/h × 2–4 h
Potassium above 3.5 before insulinK⁺ > 3.5 mmol/L
Regular insulin IV at 0.1 U/kg/h0.1 U/kg/h
Resolved: ketones < 0.6, pH ≥ 7.3BHB < 0.6 mmol/L
01 · Defined byGlucose, ketones and acidosis required
DKA (2024 consensus) needs all three: glucose ≥ 200 mg/dL or known diabetes; β-hydroxybutyrate ≥ 3.0 mmol/L (or urine ketones ≥ 2+); and pH < 7.3 and/or bicarbonate < 18 mmol/L.
02 · FirstPotassium above 3.5 before insulin
If K⁺ is < 3.5 mmol/L, hold insulin and give potassium about 10 mmol/h until K⁺ > 3.5; once K⁺ < 5.0, add 20–30 mmol potassium per liter to keep it 4–5 mmol/L.
03 · GiveRegular insulin IV at 0.1 U/kg/h
Run a fixed-rate IV regular insulin infusion at 0.1 U/kg/h; when glucose falls below 250 mg/dL, add 5–10% dextrose and drop to 0.05 U/kg/h, holding glucose near 200 until ketoacidosis resolves.
01
Diagnosis & monitoring
Work-upResolved: ketones < 0.6, pH ≥ 7.3 must knowDKA has resolved when blood ketones are < 0.6 mmol/L and venous pH ≥ 7.3 or bicarbonate ≥ 18 mmol/L (ideally glucose < 200); do not use anion gap or urine ketones.
Grade severity: pH 7.25, 7.0 cut-pointsMild DKA: pH 7.25–7.30 or HCO₃⁻ 15–18, alert (ward). Moderate: pH 7.0–7.25, HCO₃⁻ 10–15 (step-down). Severe: pH < 7.0, HCO₃⁻ < 10, ketones > 6.0 or stupor (ICU).
Measure blood β-hydroxybutyrate, not urine ketonesDiagnose and track DKA with venous or capillary β-hydroxybutyrate: the urine nitroprusside test misses β-hydroxybutyrate, underestimates ketosis early and overestimates it during recovery.
Glucose every 1–2 h; labs every 4 hCheck capillary glucose every 1–2 hours; draw electrolytes, phosphate, creatinine, β-hydroxybutyrate and venous pH every 4 hours, plus a potassium 2 hours after insulin starts.
Correct sodium for hyperglycemiaHyperglycemia lowers measured sodium by dilution: add 1.6 mEq/L to the measured sodium for every 100 mg/dL of glucose above 100 mg/dL.
02
Do right now
In this orderFirst moves
1
→Isotonic fluids 500–1000 mL/h first500–1000 mL/h × 2–4 h
2
→Potassium above 3.5 before insulinK⁺ > 3.5 mmol/L
3
→Regular insulin IV at 0.1 U/kg/h0.1 U/kg/h
4
Find the trigger: infection, MI, missed insulin
Why each step
Isotonic fluids 500–1000 mL/h firstStart 0.9% saline or a balanced crystalloid (lactated Ringer’s, Plasma-Lyte) at 500–1000 mL/h for the first 2–4 hours, then adjust to volume status; replace the deficit over 24–48 hours.
Potassium above 3.5 before insulinIf K⁺ is < 3.5 mmol/L, hold insulin and give potassium about 10 mmol/h until K⁺ > 3.5; once K⁺ < 5.0, add 20–30 mmol potassium per liter to keep it 4–5 mmol/L.
Regular insulin IV at 0.1 U/kg/hRun a fixed-rate IV regular insulin infusion at 0.1 U/kg/h; when glucose falls below 250 mg/dL, add 5–10% dextrose and drop to 0.05 U/kg/h, holding glucose near 200 until ketoacidosis resolves.
Find the trigger: infection, MI, missed insulinLook for the precipitant: infection, missed or inadequate insulin, MI, stroke, pancreatitis, SGLT2 inhibitor; get an ECG (ischemia, hyperkalemic changes) and cultures — fever points to infection, not DKA itself.
03
Management
OrdersMild–moderate DKA: subcutaneous rapid-acting insulinUncomplicated mild or moderate DKA can be treated with subcutaneous rapid-acting insulin analog every 1–2 hours in the ED or step-down unit; use IV insulin for severe DKA or HHS.
Basal insulin 1–2 h before stopping dripGive subcutaneous basal insulin 1–2 hours before stopping the infusion to prevent rebound ketoacidosis; estimate total daily dose at 0.5–0.6 U/kg in insulin-naive patients, about 0.3 U/kg if frail or kidney failure.
04
Red flags & don'ts
Avoid harmNo routine bicarbonate unless pH < 7.0 avoidDo not give bicarbonate routinely — fluids and insulin clear the acidosis, and bicarbonate risks hypokalemia and cerebral edema; consider 100 mmol in 400 mL sterile water every 2 h only while pH < 7.0.
Hypokalemia and hypoglycemia: the treatment harms complicationThe commonest treatment complications are hypokalemia (about half of patients; K⁺ ≤ 2.5 raises mortality) and hypoglycemia (16–28%); prevent them with potassium in the fluids, dextrose below 250 and hourly glucose checks.
05
DKA or alcoholic ketoacidosis?
Commonly confused| Glucose | ≥ 200 mg/dL or known diabetes |
|---|---|
| Setting | Insulin deficiency, missed doses, infection |
| First fluid | Isotonic crystalloid; dextrose once glucose < 250 |
| Insulin | IV infusion until ketoacidosis resolves |
| Give first | Potassium if K⁺ < 3.5 |
06
Commonly confused
Tell apartEuglycemic DKA: glucose < 200, SGLT2 inhibitorsAbout 10% of DKA presents with glucose < 200 mg/dL — most often from SGLT2 inhibitors, also pregnancy, starvation or alcohol. Stop the SGLT2 inhibitor and start dextrose with the saline from the outset.
Normal-gap acidosis after saline is not DKALarge saline volumes cause hyperchloremic normal-anion-gap acidosis during recovery; mistaking a low bicarbonate for persistent DKA delays the switch to subcutaneous insulin — follow ketones and pH instead.
07
More detail
ReferenceShow 7 reference facts
Cerebral edema is rare in adults (mostly a pediatric complication) but carries about 30% mortality; suspect it with headache or falling consciousness during treatment and treat with mannitol.
Adding basal insulin 0.15–0.3 U/kg subcutaneously while the IV infusion runs shortens time to resolution and prevents rebound hyperglycemia without more hypoglycemia; continue a patient’s usual basal dose.
Phosphate falls during treatment but routine replacement does not help; give potassium phosphate only for severe hypophosphatemia with weakness, respiratory or cardiac compromise, and watch calcium.
Older adults and patients with heart failure or end-stage kidney disease need smaller boluses (about 250 mL) with frequent hemodynamic reassessment to avoid volume overload.
Missed insulin causes up to 75% of recurrent DKA: discharge with insulin supply, sick-day and ketone-testing teaching, CGM where possible, and follow-up within 2–4 weeks.
After SGLT2-associated DKA in type 2 diabetes, routine restart is not recommended; SGLT2 inhibitors are not recommended in type 1 diabetes.
Serum amylase and lipase are often elevated in DKA even without pancreatitis; abdominal pain that persists after acidosis resolves needs a separate evaluation.
D-K-A: Diabetes or glucose, Ketones, Acidosis — and potassium before insulin, every time.
Sources · Umpierrez GE et al. Hyperglycemic Crises in Adults With Diabetes: A Consensus Report (ADA/EASD/JBDS/AACE/DTS). Diabetes Care 2024;47:1257–1275, doi:10.2337/dci24-0032 (open copy read: Diabetologia 2024;67:1455–1479, PMC11343900) · ADA. 16. Diabetes Care in the Hospital: Standards of Care in Diabetes—2026. Diabetes Care 2026;49(Suppl 1) · Merck Manual Professional — Acute Complications of Diabetes Mellitus (DKA, HHS, alcoholic ketoacidosis) · Merck Manual Professional — Medications for Diabetes Mellitus Treatment · Starter sheet built from the verified AGACNP fact map (facts reviewed 2026-10-15).