Skip to content
medschool

Educational content. Not a substitute for clinical judgement. Read full disclaimer.

Endocrinology
Endocrinology

DKA Management on the Ward

A step-by-step protocol for diabetic ketoacidosis aligned with JBDS-IP guidance, with the points where junior doctors most often get into trouble.

Published
10 May 2026
Read time
3 min read
Procedure GuideFoundation / Junior Doctor

DKA is one of the few endocrine emergencies where a junior doctor is genuinely the first responder. The protocol is well-defined; the traps are predictable.

Diagnosis

All three must be present:

  1. Hyperglycaemia — capillary glucose >11.0 mmol/L (or known diabetes)
  2. Ketonaemia — capillary blood ketones ≥3.0 mmol/L (or significant ketonuria 2+)
  3. Acidosis — venous pH <7.30 or bicarbonate <15 mmol/L

Clinical pearl

Euglycaemic DKA exists — most often with SGLT2 inhibitors. Don't be falsely reassured by a glucose of 9 mmol/L if the patient is acidotic and ketotic.

First hour

Resuscitation fluid

Adult DKA is profoundly fluid-deplete (often 6-9 L). Start with 0.9% saline 1 L over 1 hour (unhurried but not delayed). If SBP <90 mmHg, give 500 mL stat and reassess.

Fixed-rate insulin infusion (FRII)

Soluble insulin (Actrapid)0.1 units/kg/hIV infusion

Use the patient's actual body weight. If the patient is already on long-acting insulin (e.g. glargine, degludec), continue it — do not stop the basal.

Initial bloods

VBG, U&E, glucose, ketones, FBC, CRP, blood cultures if febrile, ECG (look for hyperkalaemia changes), pregnancy test in women of reproductive age. Don't forget the urinalysis and any source-of-precipitation workup.

Hours 1-6 — the volume and potassium phase

TimeFluidPotassium replacement
0-1 h1 L 0.9% salineNone in this bag
1-3 h1 L 0.9% saline over 2 h20-40 mmol KCl/L per K+
3-5 h1 L 0.9% saline over 2 h20-40 mmol KCl/L per K+
5-9 h1 L 0.9% saline over 4 h20-40 mmol KCl/L per K+
9-12 h1 L 0.9% saline over 4 h20-40 mmol KCl/L per K+
Serum K+ (mmol/L)KCl added to each litre
> 5.5None
3.5 - 5.540 mmol
< 3.5Senior review — needs IV potassium in HDU

Red flag

Insulin drives potassium intracellularly. A normal serum potassium at the start can plummet within 2-3 hours. Recheck VBG at 1, 2, 4, 8, 12, 24 hours — and adjust potassium replacement at each.

When the glucose drops

When glucose <14 mmol/L, switch one of the infusion bags to 10% dextrose at 125 mL/h running alongside the saline. This lets you continue the FRII (which is still resolving the ketosis) without inducing hypoglycaemia.

Do not stop the insulin when the glucose normalises. The treatment endpoint is resolution of the ketoacidosis, not the glucose.

Resolution criteria

All three:

  • Venous pH >7.30
  • Bicarbonate >15 mmol/L
  • Capillary ketones <0.6 mmol/L

At resolution, transition to:

  1. The patient's usual subcutaneous insulin (or a starter regimen if new diagnosis)
  2. A first subcutaneous dose 30-60 minutes before stopping the IV infusion (overlap prevents rebound)
  3. A meal, if tolerated

Common errors

  • Stopping the basal insulin — leads to recurrent DKA when the FRII comes down.
  • Stopping the FRII when glucose normalises — the patient is still ketotic.
  • Ignoring potassium — the commonest avoidable harm in DKA care.
  • Not finding the precipitant — infection, MI, missed insulin, new diagnosis, drug (steroids, SGLT2i). Treat the cause as well as the ketosis.

Key points

  • Diagnose on the triad — glucose, ketones, acidosis.
  • Fluid first, then fixed-rate insulin (0.1 U/kg/h) plus continued basal.
  • Potassium is the silent killer — recheck every 1-2 hours.
  • Switch to 10% dextrose when glucose <14; don't stop the insulin.
  • Treat to resolution of ketoacidosis, not just glucose.

References

  1. [1]Joint British Diabetes Societies Inpatient Care Group. The management of diabetic ketoacidosis in adults. JBDS-IP, 2023 update. Link

About the author

Dr. Sara HassanVerifiedVerified medical practitioner

MBBS, MRCP

Endocrinology· Oxford University Hospitals NHS Foundation Trust

Endocrinology specialist registrar with an interest in inpatient diabetes and adrenal disease. Writes the endocrinology pearls for MedSchool.

More in Endocrinology