Diabetic ketoacidosis

Act now

1. 1

   Large-bore IV access. If systolic BP <90: 500 mL 0.9% sodium chloride over 10–15 minutes, repeat if needed and call a senior.

3. 2

   Otherwise 0.9% sodium chloride 1 L over the first hour.

5. 3

   Start a fixed-rate IV insulin infusion (FRIII) at 0.1 units/kg/hour.

7. 4

   Continue the patient's usual long-acting insulin at the usual dose and time.

Assess

• ABCDE, GCS, fluid status, weight (estimate if needed), precipitant (infection, missed insulin, new diagnosis, SGLT2 inhibitor).
• Severe DKA (consider HDU): ketones >6, bicarbonate <5, pH <7.0, K⁺ <3.5 on admission, GCS <12, SpO₂ <92%, systolic BP <90, HR >100 or <60, anion gap >16.

Investigations

• Capillary glucose and ketones hourly; venous gas (pH, bicarbonate, K⁺) at 60 minutes, 2 hours, then 2-hourly.
• U&E, FBC, cultures, ECG, CXR and urine as indicated; pregnancy test where relevant.

Manage

• Typical fluid course after the first litre: 0.9% saline with KCl 1 L over 2 h, 1 L over 2 h, 1 L over 4 h, 1 L over 4 h, 1 L over 6 h. Slower in young adults 18–25, older people, pregnancy, heart or renal failure.
• Potassium in each litre: K⁺ >5.5 none; 3.5–5.5 add 40 mmol/L; <3.5 senior review — extra K⁺ needed.
• Targets: ketones fall ≥0.5 mmol/L/h, bicarbonate rise ≥3 mmol/L/h, glucose fall ≥3 mmol/L/h. If not met, check the pump, then increase insulin by 1 unit/h.
• When glucose <14 mmol/L: add 10% glucose at 125 mL/h alongside the saline; consider reducing FRIII to 0.05 units/kg/h.
• Resolution: ketones <0.6 mmol/L and venous pH >7.3. Restart subcutaneous insulin with a meal; stop FRIII 30–60 minutes after the short-acting dose.

Escalate when

Doses and prescribing

Check the BNF and your local formulary before prescribing.