Paediatric DKA Two-Bag Calculator

For patients under 18 years only
Adult diabetic ketoacidosis follows a different protocol with different fluid rates, a different insulin approach and no weight bands. Do not use this tool for an adult.

A bedside calculation aid for the two-bag method. Clinical thresholds follow the Canadian Paediatric Society practice point on paediatric diabetic ketoacidosis, with the CPEG-endorsed TREKK algorithm and ISPAD 2022 beneath it.

Clinical judgment remains the responsibility of the treating clinician. This tool performs arithmetic on figures you enter and compares them with published thresholds. It does not examine the patient, does not diagnose, and does not decide anything. Every figure must be checked by the person prescribing before it is acted on, and responsibility for that check, and for the care given, rests with the operator.

It has not been reviewed or endorsed by any organisation whose documents it cites.

Nothing you enter is transmitted, and no identifiers are asked for. Entries stay on this device until you press Reset Patient.

Provided without warranty of any kind. The author disclaims any liability, loss or damage arising from its use.

By continuing you accept these terms.

2B
Paediatric DKA Two-Bag
Under 18 years · CPS · TREKK · ISPAD aligned
Required *
Not Graded

New to the two-bag method?

Two bags of fluid run at the same time into the same line. They are identical except for dextrose — same saline, same potassium. One has none, one has dextrose.

Because only the dextrose differs, sliding volume from one bag to the other changes the sugar the child receives and nothing else. The total fluid, the sodium and the potassium all stay exactly the same. That is the whole point of the method: you can chase the glucose without disturbing the rehydration.

A third pump carries the insulin. It runs at a steady dose and is not used to control the glucose — the dextrose slider does that.

Work left to right through the tabs: confirm the diagnosis, set up your fluids, run the bags, then log each set of bloods and let the tool tell you what to change.

Before You StartPaediatric DKA · under 18 years

Is this the right tool for this patient?
This is for diabetic ketoacidosis in a patient under 18. Adult DKA follows a different protocol with different fluid rates and no weight bands. Hyperosmolar hyperglycaemic state needs more fluid, not less, and is managed differently again.

Enter the weight in the header — nothing calculates without it — then the age below. Everything else on this page is optional, but the more you enter the more the tool can check.

Confirm the DiagnosisAll three criteria required

Cerebral Injury Risk ProfileRecorded once at presentation

Electrolytes & Derived ValuesFlowsheet

Anion gap
Na − Cl − HCO₃ · >12 diagnostic
Anion gap · with K
normal 16 ± 2
Corrected Na
Na + 0.3 × (glu − 5)
Corrected Na · alt
Na + 0.36 × (glu − 5.6)
Effective osmolality
glu + 2 × (Na + K) · 275–295