Endocrine · Topic 1 of 14

Diabetic Ketoacidosis (DKA)

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Endocrine · hyperglycemic crisis

Diabetic Ketoacidosis (DKA)

Glucose ≥ 200 or known diabetes, ketones ≥ 3.0 and acidosis. Fluids first, potassium over 3.5, then an insulin drip until ketoacidosis clears.

01 · Defined byGlucose ≥ 200, ketones ≥ 3.0, pH under 7.3

02 · Before insulinPotassium over 3.5 mmol/L

03 · The dripRegular insulin IV 0.1 U/kg/h

What causes it

Always find the trigger — fever points to infection, not DKA itself

Common triggers

InfectionMissed or inadequate insulinMIStrokePancreatitis

Euglycemic DKA (glucose under 200)

SGLT2 inhibitorsPregnancyStarvationAlcohol

Diagnosis: all three required

2024 consensus: glucose (or known diabetes), ketones and acidosis

Glucose ≥ 200 mg/dL or known diabetes

β-hydroxybutyrate ≥ 3.0 mmol/L (or urine ketones ≥ 2+)

pH under 7.3 and/or bicarbonate under 18 mmol/L

Insulin deficiency makes ketoacids; osmotic diuresis wastes water, Na⁺ and K⁺

About 10% present with glucose under 200 (euglycemic DKA)

Track blood β-hydroxybutyrate, not urine ketones

Corrected Na⁺: add 1.6 per 100 mg/dL glucose over 100

Amylase and lipase rise in DKA without pancreatitis

Older ADA (2009) criteria required glucose over 250 mg/dL and bicarbonate ≤ 18. The urine nitroprusside test misses β-hydroxybutyrate: it underestimates ketosis early and overestimates it in recovery. Abdominal pain that persists after the acidosis clears needs its own workup.

Grade severity

Severity sets the level of care

Mild: pH 7.25–7.30 or HCO₃⁻ 15–18, alert → ward

Moderate: pH 7.0–7.25, HCO₃⁻ 10–15 → step-down

Severe: pH under 7.0, HCO₃⁻ under 10, BHB over 6.0 or stupor → ICU

Red flags

K⁺ under 3.5 mmol/L hold insulin

K⁺ ≤ 2.5 raises mortality replace K⁺

pH under 7.0, HCO₃⁻ under 10 or stupor admit ICU

Headache or falling consciousness during treatment cerebral edema

Glucose under 250 mg/dL on the drip add dextrose

SGLT2 inhibitor on board stop the drug

Treatment

Fluids, potassium, insulin — continue until ketoacidosis resolves, not until glucose normalizes

First moves, in order

Isotonic crystalloid 500–1000 mL/hfirst 2–4 h, then adjust to volume status

→

Check K⁺ before insulinunder 3.5: hold insulin, give K⁺ about 10 mmol/h

→

Regular insulin IV 0.1 U/kg/hfixed rate

→

Find the triggerECG and cultures

Fluidsreplace the deficit

0.9% saline Lactated Ringer’s Plasma-Lyte

500–1000 mL/h for 2–4 h, deficit over 24–48 h

Older, HF or dialysis: about 250 mL boluses

Potassiumkeep 4–5 mmol/L

Potassium 20–30 mmol per liter

Once K⁺ under 5.0, add 20–30 mmol per liter

Under 3.5: hold insulin until K⁺ over 3.5

Insulinuntil resolved

Regular insulin IV 0.1 U/kg/h

Fixed-rate IV infusion for severe DKA

Uncomplicated mild–moderate: SC rapid-acting analog every 1–2 h is an option

Dextroseglucose under 250

Dextrose 5–10% Insulin 0.05 U/kg/h

Add dextrose, cut insulin to 0.05, glucose near 200

Euglycemic DKA: dextrose from the start

Transitionprevent rebound

Basal insulin SC

Basal insulin 1–2 h before stopping the drip

Daily dose 0.5–0.6 U/kg naive · about 0.3 if frail or kidney failure

BicarbonatepH under 7.0 only

No routine bicarbonate — fluids and insulin clear the acidosis

Risks hypokalemia and cerebral edema

More detail

Bicarbonate, if considered, while pH under 7.0100 mmol in 400 mL sterile water every 2 h

Basal insulin 0.15–0.3 U/kg SC during the dripfaster resolution, less rebound, no more hypoglycemia; continue a usual basal dose

Phosphate only for severe deficit with symptomsweakness, respiratory or cardiac compromise; give potassium phosphate and watch calcium

Cerebral edema: rare in adults, about 30% mortalitymostly pediatric; treat with mannitol

Transition caveatADA 2026 continues the infusion 1–2 h after the first SC dose in DKA/HHS

The 2024 consensus holds insulin for K⁺ under 3.5; older ADA protocols and Merck use 3.3 mEq/L. Merck still gives 1–1.5 L of 0.9% saline in the first hour; balanced crystalloids resolve DKA faster with less hyperchloremic acidosis.

Monitoring and resolution

Resolved = ketones and pH, not anion gap or urine ketones

Capillary glucose every 1–2 h

Lytes, phosphate, creatinine, BHB, venous pH every 4 h

Potassium 2 h after insulin starts

Resolved: BHB under 0.6 and pH ≥ 7.3 or HCO₃⁻ ≥ 18

Normal-gap acidosis after saline is not persistent DKA

Hypokalemia (about half) and hypoglycemia (16–28%) follow treatment

Ideally glucose is also under 200 at resolution. Mistaking a saline-driven low bicarbonate for ongoing DKA delays the switch to subcutaneous insulin.

DKA or alcoholic ketoacidosis?

Both are anion-gap ketoacidosis — glucose and the first drug differ

	DKA	Alcoholic ketoacidosis
Glucose	≥ 200 mg/dL or known diabetes	Low, normal or mildly raised
Setting	Insulin deficiency, missed doses, infection	Alcohol binge, vomiting, starvation
First fluid	Isotonic crystalloid; dextrose once glucose under 250	Dextrose in 0.9% saline from the start
Insulin	IV infusion until ketoacidosis resolves	Only if glucose over 300 mg/dL
Give first	Potassium if K⁺ under 3.5	Thiamine

Discharge and follow-up

Missed insulin causes up to 75% of recurrent DKA

Discharge with an insulin supply

Teach sick-day rules and ketone testing; CGM where possible

Follow-up within 2–4 weeks

After SGLT2-associated DKA, don't routinely restart it

SGLT2 inhibitors are not recommended in type 1 diabetes

Pearl

D-K-A: Diabetes or glucose, Ketones, Acidosis — and potassium before insulin, every time.

Sources · Hyperglycemic Crises in Adults With Diabetes: A Consensus Report (ADA/EASD/JBDS/AACE/DTS, Diabetes Care 2024) · ADA Standards of Care 2026, Section 16: Diabetes Care in the Hospital · Acute Complications of Diabetes Mellitus (Merck Manual Professional) · Medications for Diabetes Mellitus Treatment (Merck Manual Professional) · Follow your institution's protocols.