Bedside Snapshot
- Normal Result
- Negative on the nitroprusside dipstick. Trace or small amounts are lab-specific and do not establish DKA.
- Significant Result
- Moderate or large ketonuria (lab grades) with glucose ≥11.1 mmol/L or known diabetes: measure blood β-hydroxybutyrate now
- Positive Suggests
- DKA (check glucose, pH and β-hydroxybutyrate)
- Starvation ketosis (intake under about 500 kcal/day)
- Alcohol-related ketoacidosis (binge, vomiting)
- Ketogenic or low-carbohydrate diet
- Negative Does Not Exclude
- DKA. Beta-hydroxybutyrate predominates in DKA and the dipstick does not detect it. Order blood β-hydroxybutyrate or venous pH
- Act Now If
- Ketonuria with glucose ≥11.1 mmol/L, or with vomiting, abdominal pain or altered mental status: check glucose, venous pH and β-hydroxybutyrate; start the DKA protocol and notify receiving team
- Watch Out For
- A negative dipstick does not exclude DKA. Urine ketones can also rise during successful treatment, so follow blood β-hydroxybutyrate and pH
Reference & Critical Ranges
Lab-specific ranges: Every lab sets its own range, by analyzer and by population. Trust the range printed on your report. The values below are typical only.
Reference ranges
| Population | Conventional | SI | Notes |
|---|---|---|---|
| Adult (urine dipstick) | Negative | Negative | Nitroprusside reagent; detects acetoacetate and acetone only |
| Adult (blood β-hydroxybutyrate) | Lab-specific | Lab-specific (mmol/L) | DKA diagnosis at ≥3.0 mmol/L; DKA resolution at <0.6 mmol/L |
| Children | Same as adult | Same as adult | Pediatric DKA thresholds: ISPAD 2022 (see Special Populations) |
Severity & critical values
| Level | Conventional | SI | What it means |
|---|---|---|---|
| Mild DKA | pH >7.25 to <7.30 or bicarbonate 15–18 mEq/L; BHB 3.0–6.0 mmol/L | pH >7.25 to <7.30 or HCO₃⁻ 15–18 mmol/L; BHB 3.0–6.0 mmol/L | Alert. Consensus level of care: regular or observation unit |
| Moderate DKA | pH 7.00–7.25 or bicarbonate 10 to <15 mEq/L; BHB 3.0–6.0 mmol/L | pH 7.00–7.25 or HCO₃⁻ 10 to <15 mmol/L; BHB 3.0–6.0 mmol/L | Alert or drowsy. Step-down or intermediate care |
| Critical: severe DKA | pH <7.00 or bicarbonate <10 mEq/L; BHB >6.0 mmol/L | pH <7.00 or HCO₃⁻ <10 mmol/L; BHB >6.0 mmol/L | Stupor or coma. ICU |
Critical values (typical; lab-specific): DKA means BHB ≥3.0 mmol/L with glucose ≥11.1 mmol/L (200 mg/dL) or known diabetes. Add pH <7.30 or bicarbonate <18 mmol/L. Severe DKA looks like BHB >6.0 mmol/L, pH <7.00, bicarbonate <10 mmol/L, or stupor or coma.
Conversion: β-hydroxybutyrate mg/dL × 0.0961 = mmol/L
Anion gap
Na⁺ − (Cl⁻ + HCO₃⁻)
The normal gap depends on the lab. The consensus reads an anion gap above 12 mmol/L as a high-gap acidosis that fits DKA. The gap alone cannot diagnose DKA or prove it has resolved.
Causes of Abnormal Results
Positive result
| Cause | Clue |
|---|---|
| Diabetic ketoacidosis (DKA) | Known diabetes or glucose ≥11.1 mmol/L (200 mg/dL); pH <7.30 or bicarbonate <18 mmol/L; polyuria, vomiting, abdominal pain, Kussmaul breathing |
| Euglycemic DKA (SGLT2 inhibitor) | Glucose <11.1 mmol/L with ketosis and acidosis; the consensus names SGLT2 inhibitors as the main cause of euglycemic DKA in recent years |
| Starvation ketosis | Intake under about 500 kcal/day (2,090 kJ/day); normal pH; normal or low glucose |
| Alcohol-related ketoacidosis | Chronic alcohol use with a recent binge, vomiting and poor intake; glucose normal or mildly raised; anion gap acidosis |
| Ketogenic or low-carbohydrate diet | Intentional diet on history; well-appearing with normal pH and glucose |
| Vomiting or hyperemesis gravidarum | Persistent vomiting; the consensus lists ketosis of pregnancy and hyperemesis in the differential |
| Precipitating illness | Infection, myocardial infarction, GI bleeding or sepsis can trigger DKA; find the trigger |
Ketonuria with DKA symptoms: Watch for vomiting, abdominal pain, polyuria, Kussmaul breathing or altered mental status. Treat any of these as a reason to get an immediate glucose, electrolytes, anion gap and venous pH.
False positive vs true positive
False positive (nitroprusside)
- Captopril and other sulfhydryl drugs: the nitroprusside test can read positive when it shouldn't
- Valproate: same trap: the nitroprusside test can read positive when it shouldn't
False negative
- β-hydroxybutyrate predominance: The main DKA ketone never registers on the dipstick. Negative or low doesn't rule out DKA
- Early DKA: Acetoacetate shows up late, so urine can underestimate early ketonemia
Interpretation & Bedside Approach
Step-by-step approach
- Is it real? Test fresh urine. If DKA is suspected, measure blood β-hydroxybutyrate (lab or capillary meter) rather than relying on the dipstick.
- How sick is the patient? Check mental status, vomiting, abdominal pain, rapid or deep breathing, hypotension and dehydration.
- Check the glucose first. Glucose ≥11.1 mmol/L (200 mg/dL) or known diabetes leans toward DKA. Normal or low glucose leans toward starvation or alcohol-related ketosis.
- Calculate derived values. Venous pH or bicarbonate, and the anion gap from the formula box above.
- Classify with the 2024 criteria. DKA requires all three criteria below, then grade severity with the table above.
- Escalate or dispose. Severe DKA or altered mental status means the ICU. Mild to moderate DKA goes to step-down or observation, per local resources.
DKA criteria (2024 consensus)
| Criterion | Threshold |
|---|---|
| Hyperglycemia or diabetes | Glucose ≥11.1 mmol/L (200 mg/dL), or known diabetes irrespective of glucose |
| Ketonemia | Blood β-hydroxybutyrate ≥3.0 mmol/L (the recommended measure). In mixed DKA/HHS, the consensus also counts ketonuria ≥2+ as significant ketonemia; semiquantitative nitroprusside testing of urine or serum is named as an alternative to blood β-hydroxybutyrate |
| Acidosis | pH <7.30 or bicarbonate <18 mmol/L |
Urine ketones vs blood β-hydroxybutyrate
| Pattern | Suggests |
|---|---|
| Urine ketones negative; glucose ≥11.1 mmol/L; low pH or bicarbonate | DKA can still be present. Order blood β-hydroxybutyrate or venous pH |
| Urine ketones positive; glucose normal; pH normal | Starvation, diet or alcohol-related ketosis. Take an intake and alcohol history |
| Urine ketones positive; glucose ≥11.1 mmol/L; pH <7.30 | DKA likely. Measure β-hydroxybutyrate and start the DKA protocol |
| Urine ketones rising while acidosis improves | β-hydroxybutyrate converting to acetoacetate during treatment. Follow β-hydroxybutyrate and pH |
| Urine ketones still positive after recovery | Urine ketones are not used to confirm resolution |
Management Priorities
Emergency: Suspected DKA (glucose ≥11.1 mmol/L or known diabetes, with ketonemia and pH <7.30 or bicarbonate <18 mmol/L)
- Stabilize: airway, breathing and circulation; IV access; point-of-care glucose and venous blood gas.
- Fluids: isotonic saline or balanced crystalloid, 500–1,000 mL/h for 2–4 h, then reassess. Use smaller boluses (for example 250 mL) in older adults or with heart or kidney failure.
- Insulin and potassium: start a fixed-rate IV regular insulin infusion at 0.1 U/kg/h once potassium is checked. Delay insulin while K⁺ is below 3.5 mmol/L; start it once K⁺ is above 3.5 mmol/L.
- Monitor and repeat: glucose every 1–2 h; electrolytes every 4 h; β-hydroxybutyrate and venous pH until resolution.
Medications
| Drug | Adult dose | Pediatric dose | Onset / key notes |
|---|---|---|---|
| 0.9% saline or balanced crystalloid | 500–1,000 mL/h for the first 2–4 h, then per volume status | Weight-based per pediatric DKA protocol | Balanced crystalloid is associated with faster DKA resolution than saline (consensus). Add 5–10% dextrose when glucose is below 13.9 mmol/L (250 mg/dL). If glucose is already below that at presentation (euglycemic DKA), start dextrose-containing fluid with insulin from the start, per medical direction |
| Regular insulin, IV infusion High-alert | 0.1 U/kg/h fixed rate. Reduce to 0.05 U/kg/h when glucose is below 13.9 mmol/L (add dextrose). Hold glucose near 11.1 mmol/L (200 mg/dL) until ketoacidosis resolves | Weight-based per pediatric DKA protocol | Start only once K⁺ is above 3.5 mmol/L. Optional initial bolus of 0.1 U/kg (IV or IM) if a delay in venous access is anticipated, per local protocol |
| Potassium chloride, IV High-alert | Below 5.0 mmol/L: 20–30 mmol per litre of IV fluid for most patients. If K⁺ is below 3.5 mmol/L: start at 10 mmol/h and delay insulin until K⁺ is above 3.5 | Weight-based per pediatric DKA protocol | Start replacement when K⁺ falls below 5.0 mmol/L; aim for 4–5 mmol/L. Check K⁺ 2 h after insulin starts, then every 4 h until DKA resolves |
| Sodium bicarbonate 8.4% | Not routine. Only if pH is below 7.0: 100 mmol sodium bicarbonate (100 mL of 8.4%) diluted in 400 mL sterile water (about 200 mmol/L, hypertonic; infuse per hospital pharmacy protocol, not by push), repeated every 2 h until pH is above 7.0. Hospital or medical-direction therapy only; never give the 8.4% solution undiluted by push | Consult pediatric DKA protocol | Bicarbonate has not improved outcomes in DKA and can cause hypokalemia (consensus). Monitor and replace potassium alongside any bicarbonate |
| Dextrose 5–10% | Added to saline when glucose is below 13.9 mmol/L (250 mg/dL) | Per pediatric DKA protocol | Keeps insulin running until ketoacidosis clears; prevents hypoglycemia |
| Thiamine (suspected alcohol-related ketoacidosis) | IV, given with or before dextrose; dose per local protocol | Per local protocol | Do not delay dextrose while waiting for thiamine |
High-alert infusions: insulin and IV potassium need an independent double-check, pump use and scheduled monitoring: glucose every 1–2 h and potassium every 4 h.
Definitive care & disposition
- Level of care: severe DKA or altered mental status goes to ICU. Mild to moderate DKA goes to step-down or observation, per resources.
- Resolution: plasma ketones below 0.6 mmol/L and venous pH ≥7.3 or bicarbonate ≥18 mmol/L (consensus). Glucose ideally below 11.1 mmol/L. Do not use urine ketones.
- Transition: start subcutaneous basal-bolus or protocol insulin with a 1–2 h overlap before stopping IV insulin.
- Precipitant and follow-up: find and treat the trigger (infection, myocardial infarction, medication). Close follow-up within 2–4 weeks may reduce recurrence (consensus).
- Alcohol-related ketoacidosis: IV saline with dextrose and thiamine. Insulin use is protocol-dependent; confirm with medical direction.
Doses are typical references. Follow local protocols, medical direction and institutional policy.
Field & Transport Considerations
Point-of-care testing
The dipstick is quick and cheap, but it only sees acetoacetate and acetone. A capillary β-hydroxybutyrate meter reads the main DKA ketone directly. The consensus flags doubt about point-of-care accuracy at high levels (≥5 mmol/L) against lab analyzers. Glucose at the bedside sets the first branch point. A venous blood gas gives pH and bicarbonate.
Before and during interfacility transport
- Obtain glucose, mental status, vital signs and, if available, β-hydroxybutyrate or venous pH.
- Record the time of first fluid and of any insulin started. Check that the pump rate matches the protocol.
- Recheck glucose during transport if the patient cannot maintain oral intake or is on insulin, per local protocol.
- Vomiting or drowsy patients need airway protection and suction. Mental status can turn fast.
Scope notes
Insulin infusions, IV potassium and bicarbonate belong to the hospital in most systems. In the field you check glucose, start IV access and give fluids per local protocol. Then you transport to a facility that can start the insulin protocol. Insulin and bicarbonate stay off the field list unless medical direction orders them. Follow local protocols and medical direction.
Special Populations
| Population | What changes | Clinical implication |
|---|---|---|
| Children & adolescents | ISPAD 2022 sets pediatric DKA thresholds and its own fluid and insulin rules, which differ from adult rules | Use the pediatric DKA protocol and weight-based dosing. Do not apply adult fluid or insulin numbers from this page |
| Pregnancy | Ketosis from vomiting or poor intake, and euglycemic DKA, are reported (consensus) | Take an intake and vomiting history. Treat dehydration, check glucose and pH, and look for hyperemesis gravidarum |
| Older adults | Higher risk of fluid overload; overlap with hyperglycemic hyperosmolar state (HHS) | Use smaller fluid boluses (for example 250 mL) with frequent reassessment (consensus) |
| Heart failure, CKD or dialysis | Higher risk of fluid overload | Cautious fluid replacement with frequent hemodynamic checks (consensus) |
| SGLT2 inhibitor users | Euglycemic DKA with glucose below 11.1 mmol/L | Check the medication list. A normal glucose does not exclude DKA |
Interfering Factors & Pitfalls
Collection & handling
| Factor | Effect | Why | Avoid / fix |
|---|---|---|---|
| Delayed or warm specimen | ↓ False − | Acetone is volatile and ketones degrade with delay | Test fresh urine promptly; keep the container covered |
| Dilute urine | ↓ False − | Dilute urine can read lower than the blood ketone level | Use blood β-hydroxybutyrate when urine looks dilute and DKA is suspected |
Medications & supplements
| Factor | Effect | Why | Avoid / fix |
|---|---|---|---|
| Captopril and other sulfhydryl drugs | False + | Reacts with the nitroprusside reagent | Measure blood β-hydroxybutyrate |
| Valproate | False + | Reported to give false-positive nitroprusside tests (consensus) | Measure blood β-hydroxybutyrate |
Physiologic & biologic
| Factor | Effect | Why | Avoid / fix |
|---|---|---|---|
| β-hydroxybutyrate converting to acetoacetate during treatment | ↑ Urine ketones | Urine ketones look worse as the acidosis improves | Follow blood β-hydroxybutyrate and pH trends |
| Hyperchloremic normal-gap acidosis after saline | Anion gap falsely reassuring | Chloride-rich fluids lower bicarbonate without a gap | Use β-hydroxybutyrate and pH; do not use the gap to confirm resolution |
| Mixed acid–base disorders | Gap misleads | Present in about one-third of patients presenting with DKA (consensus) | Read pH and bicarbonate together with the gap |
Assay & device
| Factor | Effect | Why | Avoid / fix |
|---|---|---|---|
| Capillary β-hydroxybutyrate meters at high concentrations | Variable | Accuracy concern against laboratory analyzers at ≥5 mmol/L (consensus) | Confirm with a laboratory sample when results are high or unexpected |
Common misinterpretations
- A negative dipstick rules out DKA. It does not.
- Rising urine ketones during treatment mean DKA is getting worse. Not necessarily. They may reflect β-hydroxybutyrate turning into acetoacetate.
- Ketonuria means DKA. It doesn't. Starvation, diet and alcohol-related ketosis cause it too.
- A normal glucose rules out DKA in an SGLT2 inhibitor user. It doesn't. Euglycemic DKA still happens.
Physiology & Test Basics
What it measures
The urine ketone test (dipstick, nitroprusside reagent) picks up acetoacetate and, less sensitively, acetone. This page covers only the urine test. It does not measure β-hydroxybutyrate, the main DKA ketone. For DKA diagnosis and monitoring, blood β-hydroxybutyrate is the preferred test.
Physiology & regulation
- Too little insulin and too little glucose to burn push lipolysis. Free fatty acids reach the liver and form ketone bodies.
- Three ketone bodies: β-hydroxybutyrate (predominant in DKA), acetoacetate (detected by nitroprusside) and acetone (volatile; fruity breath).
- Early on, urine ketones trail blood levels. Later in DKA they can overstate severity (consensus).
- Ketoacids use up bicarbonate. The result is an anion gap acidosis.
How it is measured
- Urine dipstick: nitroprusside reagent strip on fresh urine; semiquantitative grades.
- Blood β-hydroxybutyrate: capillary point-of-care meter or venous sample on a laboratory analyzer.
- Specimen handling: test fresh urine promptly; follow the strip manufacturer's storage and expiry instructions.
Why it matters
Ketonuria is a fast screen. It does not confirm DKA. In the ED and ICU, glucose, pH and blood β-hydroxybutyrate decide together: the diagnosis, its severity and the level of care.
Clinical Pearls
Negative dipstick does not exclude DKA: Nitroprusside misses β-hydroxybutyrate, the main DKA ketone. Suspect DKA? Order blood β-hydroxybutyrate or venous pH.
Glucose sets the branch point: Ketones with glucose ≥11.1 mmol/L or known diabetes: screen for DKA. Normal glucose points you toward starvation or alcohol-related ketosis.
Urine ketones can rise while the patient improves: β-hydroxybutyrate turns into acetoacetate, and the dipstick can look worse even when treatment works. Track glucose, pH and blood β-hydroxybutyrate instead.
SGLT2 inhibitors and normal glucose: Euglycemic DKA can show up with glucose below 11.1 mmol/L. Whenever the med history and symptoms fit, check blood β-hydroxybutyrate and pH.
Alcohol-related ketoacidosis: Glucose is often normal or only mildly raised. The usual treatment is IV saline with dextrose and thiamine. Insulin depends on protocol, so confirm with medical direction before any infusion starts.
Add dextrose before the glucose falls too far: Once glucose is below 13.9 mmol/L (250 mg/dL), add 5–10% dextrose and cut insulin to 0.05 U/kg/h. Keep it running until ketoacidosis clears.
References
- Hyperglycemic crises in adults with diabetes: a consensus report. Joint consensus of the American Diabetes Association, European Association for the Study of Diabetes, Joint British Diabetes Societies, American Association of Clinical Endocrinology and Diabetes Technology Society. Diabetes Care. 2024;47(8):1257–1275. https://doi.org/10.2337/dci24-0032
- Hyperglycaemic crises in adults with diabetes: a consensus report (same consensus, Diabetologia edition). Diabetologia. 2024. https://doi.org/10.1007/s00125-024-06183-8
- Glaser N, Fritsch M, Priyambada L, et al. ISPAD Clinical Practice Consensus Guidelines 2022: Diabetic ketoacidosis and hyperglycemic hyperosmolar state. Pediatr Diabetes. 2022;23(7):835–856. https://doi.org/10.1111/pedi.13406
- Ghimire P, Dhamoon AS. Ketoacidosis. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; updated 2023 Aug 8. https://www.ncbi.nlm.nih.gov/sites/books/NBK534848/
Medical Disclaimer
- For Educational Purposes Only: This content is intended for educational reference and should not be used for clinical decision-making.
- Not a Substitute for Professional Judgment: Always consult your local protocols, institutional guidelines, and supervising physicians.
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